Purpose of steel 12x18n10t. Blog about sharpening. G and M codes
ALL austenitic steels begin to become magnetic after cold hardening.
No, not all, but only austenitic-martensitic (and only after appropriate processing) or austenitic-ferritic classes.
the face-centered lattice of austenite is metastable at room temperature, i.e. with any sufficient increase in the energy of the closed system, it will be reconstructed into a more stable body-centered lattice for a given temperature.
Your argument is wrong. Firstly, it is not the austenite lattice that should be discussed, but the iron lattice. This is due to the fact that the stability of the fcc lattice of iron (under given external conditions) depends on which elements are dissolved in it. From literature (Gulyaev, Lyakishev, Bernstein I don't give full links. too lazy to type ) fcc metals, nitrogen and carbon are known to stabilize austenite, and bcc metals stabilize ferrite. And they all dissolve in both austenite and ferrite. This seems like a trifle, but I consider this point to be the starting point for further reasoning. Although, if you like, I will agree with the term fcc lattice of austenite, because I understand it.
Secondly, to solve the question of which iron lattice is stable under given conditions (chemical composition of the alloy, temperature, normal pressure), you need to turn to the corresponding state diagram . For example, for the “Fe-Ni-Cr” system there is an isothermal section with a description of this system (see Gulyaeva p. 412). Analysis of the ternary alloy "Fe-18Cr-10Ni" shows that at 20°C and 1 atm. the fcc lattice of iron (austenite) is stable (equilibrium). note that heating such an alloy does not lead to a polymorphic phase transition (delta iron has a bcc lattice, but with a large period).
Question: And if we perform plastic deformation of the alloy “Fe-18Cr-10Ni” (% C = 0), which lattice is stable (stable over time)?
Answer: Directly during deformation, when the pressure is much more than 1 atm. The bcc lattice of iron is stable (this is from practice; I have not seen such state diagrams). During deformation, transformation occurs, but as soon as the pressure returns to 1 atm. The fcc lattice is stable. In this case, a metastable alpha phase can remain in the structure for some time, which, when heated, will quickly turn into gamma.
Question: What if you cool it to -196°C and then heat the “Fe-18Cr-10Ni” alloy?
Answer: Alpha iron (alpha solid solution) is stable at low temperatures. When returning to 20°, a transformation will occur (according to the diff. mechanism), but due to the low self-diffusion of iron it will take a long time (several years).
However, we do not have a ternary alloy, but steel 12Х18Н10Т. Adding carbon, Mn, Si and Ti to our ternary system complicates the system (you can't draw a diagram anymore), but there is a way out. Here he is.
This diagram shows which class the steel of a given chemical grade will belong to. composition in terms of equivalent % Ni and Cr. I put two points on the diagram: red and green. The red dot corresponds to the grade composition of steel 12Х18Н10Т (GOST 5632-72), but with a lower limit for Cr (17%) and an upper limit for Ni (11%). Green dot, the opposite situation - this corresponds to the brand composition of our 12Х18Н10Т, but with an upper limit for Cr (19%) and a lower limit for Ni (9%). I took the carbon content equal to 0.12% in both cases, and titanium was not taken into account due to its small influence. For the red dot: eq.%N~15.5; eq.%Cr~18.5. For the green dot: eq.%N~13.5; eq.%Cr~20.5.
In other words, within the grade composition, steel 12Х18 Н10Т can be either austenitic or austenitic-ferritic. If metallurgists also blow carbon down to 0.02% or decarbonization of the surface occurs, then it (the steel point) will slide into the A+F+M region.
At the same time, with an average composition and 0.12% C, steel 12Х18Н10Т is considered purely austenitic, which is stated in GOST 5632-72, as well as in metallurgical literature (to whom GOSTs and Dear metallurgists, our good teachers, it’s not a decree, let’s go to the garden: wink:)
I buy a sink, bring it home, poke it with a magnet, the magnet sticks like a freak.
Today I checked my sink at work with a magnet. Doesn't magnetize. Maybe it was hardened after the stamp? Or maybe it’s not 18-10, but 18-25? Of course not. Most likely, my 18-10 corresponds to the red dot, and yours, Nikolai, corresponds to the green one.
And the last question (for Vitaly). Why do they harden austenitic steels, because after hardening they retain this austenite in their structure in an amount of 100%, which means the yield strength and hardness will be exactly the same as before hardening?
Answer. In this case, hardening does not aim to obtain martensite, but to dissolve chromium carbides in austenite. On the one hand, such a single-phase, hardened structure has higher plasticity, which cannot have a positive effect on CPD processes. But, most importantly, the presence of chromium carbides in the steel structure along the grain boundaries leads to the development of intergranular corrosion, because the formation of Cr 23 C 6 carbides depletes the border areas of the grain in chromium and a local decrease in corrosion resistance occurs. Vitaly, keep in mind that when hardened steel 12Х18Н10Т is heated, intense (0.5-1 hour) release of chromium carbides occurs at temperatures above 450°C.
P.S. Regarding the problem of cutting austenitic steels, I think we need to create a branch (if not already created).
Modified on September 20, 2016 by ilia-ilich(Abrasive tool) – a cutting tool designed for abrasive processing (GOST 21445). Consists of abrasive materials (grains) held together by a bond. Typically hard (eg grinding wheels, stones) and soft (eg sandpaper, belts, pastes). They are also classified according to geometric shape, type of abrasive material, grain size, bond, hardness and structure.
Ligaments are inorganic and organic. Inorganic binders include ceramic, metal, and magnesium. Organic - bakelite, glyphthalic, vulcanite.
Ceramic bond
It is a sintered mixture of refractory clay, feldspar, quartz, talc and other materials. To increase plasticity, adhesives are added. Silicon carbide (SC), aluminum oxide (OA), electrocorundum, carborundum, etc. are used as abrasives. Ceramic bond abrasives can be made by melting or sintering raw materials. The ceramic bond allows the production of tools of any grain size. It provides high strength, rigidity, water and heat resistance. The disadvantages include the fact that such a bond gives the abrasive tool increased fragility, to reduce which sulfur impregnation can be used. The ceramic bond is the most common because its use for abrasive tools is rational for the largest number of operations.
Metal bundle
Used only for tools that use diamond or CBN as an abrasive. The metal bond has high wear and water resistance, a dense structure, but has a tendency to grease the working surface of the tool. The binder is produced in several ways - by pressing and sintering, galvanic method and casting. The wear of diamond tools with a metal bond is much slower than abrasive ones, which is explained not only by the hardness of diamond or CBN, but also by their increased ability to hold them in the bond. But when processing high-strength steels, the bond is not strong enough, so the consumption of diamonds and CBN increases. To increase the adhesion forces of diamond grains, the latter are metalized, and then the diamond-bearing layer is pressed and sintered. Along with the popular copper-tin base M2-01 (M1), the Kiev Institute of Superhard Materials (Ukraine) uses two more types of metal bonds: on a copper-tin base with the addition of iron oxide (M3) and on a cobalt base (MO3).
Magnesium ligament
Consists of caustic magnesite and magnesium chloride. The circles on this bond are heterogeneous, wear out quickly and unevenly, and are hygroscopic. They are used for dry grinding. The only advantage of the bunch is that these circles work with little heating of the processed products. Used with carborundum or electrocorundum abrasive powders. One of the disadvantages of magnesium binder is a decrease in mechanical strength during long-term storage.
Glypthal bond
It is a synthetic resin made from glycerol. on and phthalic anhydride. They are made by mixing abrasive grain (usually green KK) with a moisturizer, and then with crushed glypthal resin. After this, the mass is rubbed through a mesh, passed through a mold and sent to drying ovens. Glypthal bonded abrasives are used for final grinding and finishing. It is believed that their water resistance and elasticity are greater than bakelite bonded abrasives, but their strength and heat resistance are less.
Bakelite bond
It is an artificial phenol-formaldehyde resin in liquid or powder form. When used for polishing, oxalic acid, aluminum/tin/chromium oxides, etc. are added to the binder. It is perhaps the most common of the organic ligaments. The positive properties of the bakelite binder are its increased wear resistance and good uniformity of the composition of the abrasive tool; the disadvantages include low heat resistance, increased brittleness at 200° C and above, and low chemical resistance.
Vulcanite bond
The basis is artificial rubber vulcanized to varying degrees of elasticity and hardness. Diamond powder is often used as an abrasive for vulcanite binders. The advantages of tools using vulcanite rubber bonds are significant wear resistance, as well as high elasticity, which ensures improved quality of the machined surface. They do not lose hardness and strength under the influence of water emulsions and at the same time are not resistant to kerosene. The bond of these wheels has low heat resistance (about 160-200°C), therefore, with increasing pressure and temperature during the grinding process, the abrasive grains are somewhat pressed into the bond, cutting deteriorates and the wheel begins to work like a finer-grained one.
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Sources:
1. www.studref.com
2. www.stroitelstvo-new.ru
3. www.arxipedia.ru
4. www.stroitelstvo-new.ru
5. Photo from Norton 2004 catalog.
ZAT (Dnepr, Ukraine)
October 15, 2019
In the Sharpening Blog itself, in recent years a large selection of articles has been compiled on the operation of this and other manicure tools, their choice, advantages and disadvantages. If you choose something from Stalex and/or follow the new products of this brand, then the information will definitely be useful to you. Take note... If you are looking for a tool with a different name, pay attention to the selection of articles. And be sure to read the information from the "" section - you are unlikely to find it anywhere else.
And by the way. Where do you sharpen? Our workshop is always at your service. Comfortable. Promptly. Qualitatively. Our services are used by manicurists from all over Ukraine.
ZAT (Dnepr, Ukraine)
October 12, 2019
ZAT (Dnepr, Ukraine)
http://www.site/
07 October 2019
Soft steels are a completely different matter. As a rule, these are inexpensive knives and few people are willing to pay for their full sharpening, choosing its reduced budget option. But the day gets interesting when the owner of the knife chooses a premium level sharpening. There is already room for development here for natural stones - from the initial stage to the finishing stones of the level, or.
For harder steels (for example, such as), the work of natural stones often begins with, and ends, for example, with or the same. Of course, this is only generalized and does not take into account complete sets, which depend, among other things. depending on the purpose of the knife and the wishes of its owner.
If we take the last year - from last summer to this summer, then three stones became a discovery for me - green and burgundy Brazilian slate (I already mentioned them above), as well as. If the first ones, together with other finishing stones, have practically solved all the issues with the finish, incl. for the same soft steels, I consider Hindostan one of the best finishing stones for kitchen knives - I like the aggressive and at the same time soft cut obtained after using this stone.
Well, the use of the same Brazilian slates on soft steels made it possible to remove Llyn Idwall from these sets. Damn it, but still - how amazingly this stone works on the M390! I have never regretted buying it.
I sharpen quite a few kitchen knives made of X30Cr13, so I pay a lot of attention to this issue. It so happens that I use Translucent Arkansas with them mainly on chefs. If I’m in the mood, I can work on it, which significantly increases durability and extends the life of the knife at least until the first edit.
I understand all the reader’s skepticism regarding the existence of cold hardening, but I myself was like that until I figured out this issue, having received a hardened edge. Before I forget, I’ll also note at this point that yes, it makes sense to use oleic acid at this stage (see the link at the end of the article). IMHO, only here it is necessary to distinguish between technical and cosmetic olein, plus monitor the thickness of the layer when applying it. Again, this is subjective, but technical olein works noticeably better.
Using the word “hardening” so boldly, I note that I have achieved an increase in the retention of the razor sharpening (when the knife shaves the hair on the arm) to 15 days without any editing. I think that for the budget X30Cr13 with its conditional 50-52 HRC (according to impressions) this is a good result.
But here there is a second side - the fragility of the edge increases significantly, after a week chips already appear on it. Interestingly, here the chips somewhat increase the aggressiveness, which the knife with the Translucent Arkansas finish cannot boast of.
To what extent does editing on musat work well with hardening? He's a bad friend. After 2-3 cases of using the musat, with the restoration of the working sharpness of the knife, you can forget about any hardening effect. Until the next sharpening, which may not be soon.
Today, the most mysterious stone for me remains. The stone works quite delicately and every time I choose a stone for finishing, my hand itself bypasses it. This season I want to wait for the right opportunity, when I have knives from different steels at the same time, plus more time, and experiment with this stone - from grinding in Jasper to its place in the set.
I have long played enough with planing hair and cutting it while hanging, but it will be very interesting for me to choose a set so that, despite all the subtlety of Jasper’s work, the output will be acceptable aggressiveness.
ZAT (Dnepr, Ukraine)
05 October 2019
Not because I do a spectral analysis of the metal with my eyes, but simply because there are not so many options here. And I don’t quite understand the words about D2 itself on Chinese replicas.
Have a nice day and sharp knives everyone!
ZAT (Dnepr, Ukraine)
October 03, 2019
Good luck everyone and take care of your time!
ZAT (Dnepr, Ukraine)
01 October 2019
September 27, 2019
September 20, 2019
Good luck and sharp tools to everyone!
ZAT (Dnepr, Ukraine)
September 17, 2019
However, I will repeat. A chamfer of the hole that is too deep allows the penetration of disinfectant solutions and water when sanitizing the instrument. Over time, rust forms, which not only violates the operating conditions of a sterile instrument in a beauty salon, but also creates problems with screw sticking during maintenance of cutters in a sharpening workshop.
Yes, the photo shows that when unscrewing the screw, its cross-shaped slot was torn off. Yes, it’s a pity for the screwdriver, but the screw would still have to be changed - it doesn’t press tightly, creating unnecessary tension at the level of the hole in the spring, which sooner or later will lead to its breakage and replacement.
I like this tool. No serious questions. It helps manicurists and sharpeners earn money. But such details, insignificant at first glance, often irritate the work, distract attention and, when servicing the clippers, lead to unnecessary expenses for both the manicurists themselves and the sharpeners...
Having been sharpening tools for many years, sometimes I come across situations when working with classic paring knives, when my clients cannot immediately choose what they need from such a knife? Today I decided to talk about an alternative to the usual vegetable knives - the Victorinox 7.6075.4 vegetable peeler, which has been working in my home kitchen for more than a year. And it works successfully.
I will not dwell in detail on the knife itself, I will only briefly note that Victorinox is a well-known Swiss company that specializes in the production of all kinds of knives. From the series of vegetable peelers that I chose, the company offers knives in different colors. In my case it is a green handle made of fibrox. In principle, if the knife will work outdoors, then it is probably better to choose a different handle color, when the knife itself will be more noticeable against the background of green grass.
The Victorinox 7.6075.4 knife is equipped with stainless steel blades that work in two directions - when cleaning towards you and away from you. At its top it has a protrusion for removing seeds. To be honest, I have never used it. If the reader is interested in detailed and complete characteristics, then Google to help - the purpose of the review is to show the capabilities of the Victorinox 7.6075.4 vegetable peeler, and not to sell you this knife.
Therefore, if you agree with the famous saying "It's better to see once than to hear seven times", then I will not escalate the situation and will immediately move on to the first part of the saying.
1. Peeling potatoes. No problem. The peel cut with a knife is very thin and can be seen through even in low light. Let me remind you, just in case, that all the work presented in the photographs was done with a knife that has been in use for more than one year.
2. Peel the carrots? No problem. It is harder and therefore the process itself occurs faster and easier than in the example with potatoes.
3. Peeling a cucumber. Of course, the cucumber is tasty, fresh and not limp. However, what else should it be? The Victorinox 7.6075.4 knife simply didn’t notice it, doing its job perfectly.
4. Peeling the apple. The apple is quite soft and sweet. The Victorinox 7.6075.4 vegetable peeler probably surprised itself at how quickly it cleaned it. Well, yes. Before cleaning I cut it in half. In the next example I won’t do this anymore))
5. Cleaning fresh tomatoes, commonly called tomatoes. Pink tomato: juicy, ripe, soft. Sweet of course. It was even a shame to clean it. Here I had to tinker longer - it took about 30-40 seconds.
6. Slicing green cucumber? Nothing could be simpler. With Victorinox 7.6075.4, even a child can cope with this task. By the way, the vegetable peeler has safe blades and I can’t imagine how it could even cut itself.
Below in the photo is the same plate, only from a different angle. And, if you want to roll cucumber rolls, then it’s probably better to take it longer than in the photographs presented.
I also wanted to peel the kiwi, but it wasn’t in the refrigerator... However, I think that six examples were enough for the reader to form his own impression of the Victorinox 7.6075 vegetable peeling knife and its capabilities.
I will add that the knife is easy to clean, the logo (after almost a year of use) has not been erased from the handle, and the knife itself has taken root in the home kitchen, becoming a good assistant to a pair of vegetable knives with regular blades.
What can I say? The sharpness of kitchen knives is a powerful thing. This is not only convenience and comfort of work, but also saving time, which is most valued these days. The Sharpening Blog previously published a review article with examples of the best commercial devices for sharpening your knives, which will help you sharpen your knives to the point of shaving a hair on your arm without much hassle.
And if you or your family cook at home, then this information will definitely be interesting to you - read the article ""...
I can understand when this is really necessary - for example, with some men's haircuts. But I don’t understand why some hairdressers prefer such a machine when performing women’s haircuts.
Hairdressing scissors have a complex geometry designed to perform various technological operations. Certain sharpening angles are also selected for them. The sharpening itself makes the blades of hairdressing scissors extremely sharp - this is not only the properties of the scissors and the steel from which they are made, the classification of the sharpener, but also the need for the hair cut with such scissors to be perfectly accurate and even, without any damage to each individually cut hair.
A hair clipper works on a completely different principle and it does not cut, but chops the hair, leaving behind split ends. That is, if the haircut itself, incl. should save you from split hairs, then at the time of cutting you are already aggravating the situation when the chopped hair becomes split at its ends.
I understand what you're thinking. But there is no need to compare budget short haircuts for men with women’s haircuts, whose hair length is up to 60-70 cm. If a man’s haircut is done once a month, then a women’s haircut is done sometimes once every 6-8 months. In the first cases, they will simply cut off the old split hair to 1-1.5 cm of its length (you may not even notice its condition).
In the examples with a woman's haircut made with a hairdressing clipper, you will have to go for more than six months and the length of the split hair in this case will increase by an average of 1-1.5 cm per month. What will the split ends of your hair look like in 3 or 4 months, when you are invited to your friends’ birthday party?
Ok. You cannot afford a haircut from a good hairdresser who has been working with quality tools for a long time. But how justified is the risk of getting a haircut from a top stylist from the nearest economy-class hairdresser, when using an inexpensive hairdressing machine he forces you to come to him month after month to cut off the split hair and damage it again during the haircut?
By the way, the same applies to men's haircuts - a good haircut from a good hairdresser will be visible even after 2-3 months without any styling. And you are lucky if you have found such a Master. He may not have the so-called hanging on his wall. diplomas from courses, seminars or annual specialized exhibitions, but he knows his business, the result of which you will notice not only getting up from his hairdressing chair, but a few months after his work.
Let me add that scissors can easily be completely disinfected, while disinfection of knife blocks of hairdressing machines comes down to wiping their body with a napkin soaked in alcohol. The maximum that is possible is an aerosol spray of a disinfectant.
But even in this case, the spraying itself occurs only on the outer surface, while only lubricant is available to the internal surfaces, protecting the knife blocks from overheating and rapid dulling.
The machine oil used for lubrication remains on the knives and gets into the hair through them. This can lead to hair damage and require additional use of special masks and hair conditioners.
On the Internet, I did not find macro photographs of what remains of the hair after cutting it with a clipper - perhaps the manufacturers of clippers simply do not want to shock the buyers of their products. But there are photographs of such cuts made with an electric razor used for shaving. Yes, it's not the same thing, but it gives you an idea of what happens at the ends of hair cut with a clipper - it may be a little better or a little worse than what is shown in the photo in the title of this article.
Look again - macro photographs taken under an electron microscope show a section of hair: on the left - made with a straight razor, on the right - cut off with an electric razor.
Similar photographs have already been shown in the Blog about Sharpening, look at them in the article "" - this is interesting even for those who are not interested in this issue. You can also find useful information, with examples of damaged hair, in the article "". If you want to have good and beautiful hair, then I strongly recommend that you pay close attention to these materials.
Thank you for your attention!
Photo: www.canyouactually.com
Designations
Description
Steel 12Х18Н10Т is used: for the manufacture of forgings of general mechanical engineering parts; chemical equipment parts; parts operating at temperatures up to +600 °C; welding machines and vessels operating in dilute solutions of nitric, acetic, phosphoric acids, solutions of alkalis and salts; parts operating under pressure at temperatures from -196 to +600 °C, and in the presence of aggressive media up to +350 °C; aircraft manufacturing parts; household consumer goods; devices and parts in the food industry; connections of equipment operating in radioactive environments and in contact with aggressive environments; as a cladding layer in the production of hot-rolled two-layer corrosion-resistant sheets; solid-rolled rings for various purposes and welded rings from sheets profiled by rotational deformation for power engineering and chemical industry equipment; cold-rolled steel and bent profiles intended for the manufacture of skins and frames for passenger car bodies; sheet metal with a thickness from 40 mm to 160 mm used in the production of shipbuilding parts and structures operating in seawater conditions; double and triple lay ropes for special working conditions; seamless cold-rolled, cold-drawn and warm-rolled pipes intended for pipelines and high-quality fittings; wire woven mesh of twill weave, used as a reinforcing material in the manufacture of asbestos steel sheets, for separating bulk solids by grain size, filtration and other purposes; spring wire intended for the production of cylindrical springs operating in air and aggressive environments (sea water, salt and chlorine solutions, sea water vapor, in tropical climates) at temperatures from -253 ° C to +300 ° C and used in turbine seals, safety valves, pumps, regulators, compressors; torsion springs; bimetallic sheets with aluminum alloy AMg6, intended for the manufacture of flat adapters for general purposes; centrifugally cast pipes used as components in the equipment of the metallurgical, mechanical engineering, glass, ceramic, mining and processing petrochemical industries, as well as intended for the manufacture of blanks and parts used in the composition of products in the aviation and nuclear industries.
Note
The steel is corrosion-resistant, heat-resistant and heat-resistant.
Stabilized chromium-nickel steel of austenitic class.
Recommended maximum long-term operating temperature is +800 °C.
Recommended maximum operating temperature for very long periods of time is +600 °C.
The temperature of intense scale formation in air is 850 °C.
Standards
| Name | Code | Standards |
|---|---|---|
| Long and shaped rolled products | B22 | GOST 1133-71, GOST 2590-2006, GOST 2879-2006 |
| Test methods. Package. Marking | B09 | GOST 11878-66 |
| Alloy steel wire | B73 | GOST 18143-72, TU 3-230-84, TU 3-1002-77, TU 14-4-867-77 |
| Metal forming. Forgings | B03 | GOST 25054-81, OST 108.109.01-92, OST 5R.9125-84, OST 26-01-135-81, TU 108.11.930-87, TU 14-1-1530-75, TU 14-1-2902 -80, TU 108.11.917-87, ST TsKBA 010-2004 |
| Ribbons | B34 | GOST 4986-79, TU 3-703-92, TU 14-1-1073-74, TU 14-1-1370-75, TU 14-1-1774-76, TU 14-1-2192-77, TU 14 -1-2255-77, TU 14-1-3166-81, TU 14-1-4606-89, TU 14-1-652-73, TU 14-1-3386-82 |
| Sheets and strips | B33 | GOST 5582-75, GOST 7350-77, GOST 10885-85, GOST R 51393-99, TU 108-1151-82, TU 108-930-80, TU 14-105-451-86, TU 14-1-1150 -74, TU 14-1-1517-76, TU 14-1-2186-77, TU 14-1-2476-78, TU 14-1-2542-78, TU 14-1-2550-78, TU 14 -1-2558-78, TU 14-1-2675-79, TU 14-1-3199-81, TU 14-1-3720-84, TU 14-1-394-72, TU 14-1-4114- 86, TU 14-1-4262-87, TU 14-1-4364-87, TU 14-1-4780-90, TU 14-1-5040-91, TU 14-1-5041-91, TU 14- 1-867-74, TU 14-229-277-88, TU 14-138-638-93, TU 14-1-3485-82, TU 05764417-038-95, TU 14-1-4212-87 |
| B30 | GOST 5632-72 | |
| Long and shaped rolled products | B32 | GOST 5949-75, GOST 7417-75, GOST 8559-75, GOST 8560-78, GOST 14955-77, GOST 18907-73, OST 1 90224-76, OST 1 90365-85, TU 14-1-686-88 , TU 14-1-1534-76, TU 14-1-1673-76, TU 14-1-2142-77, TU 14-1-2537-78, TU 14-1-2972-80, TU 14-1 -3564-83, TU 14-1-3581-83, TU 14-1-377-72, TU 14-1-3818-84, TU 14-1-3957-85, TU 14-1-5039-91, TU 14-1-748-73, TU 14-11-245-88, TU 14-131-1110-2013, TU 14-1-1271-75 |
| Steel pipes and connecting parts for them | B62 | GOST 9940-81, GOST 9941-81, GOST 11068-81, GOST 14162-79, GOST 19277-73, TU 14-159-165-87, TU 14-3-1109-82, TU 14-3-1120- 82, TU 14-3-1574-88, TU 14-3-308-74, TU 14-3-769-78, TU 1380-001-08620133-93, TU 14-159-249-94, TU 14- 159-259-95, TU 1380-001-08620133-05, TU 14-158-135-2003, TU 14-3R-110-2009, TU 14-3R-115-2010, TU 14-131-880-97 , TU 14-225-25-97, TU 14-158-137-2003, TU 95.349-2000, TU 14-3-1654-89, TU 1333-003-76886532-2014 |
| Common parts and components for various machines and mechanisms | G11 | GOST R 50753-95 |
| Calculation and design standards | B02 | OST 1 00154-74 |
| Classification, nomenclature and general norms | IN 20 | OST 1 90005-91 |
| Blanks. Blanks. Slabs | AT 21 | OST 1 90176-75 |
| Blanks. Blanks. Slabs | B31 | OST 3-1686-90, OST 95-29-72, OST 1 90241-76, OST 1 90284-79, OST 1 90342-83, OST 1 90393-90, OST 1 90397-91, OST 1 90425-92, TU 3-1083-83, TU 14-105-495-87, TU 14-1-1214-75, TU 14-1-1924-76, TU 14-132-163-86, TU 14-1-3844- 84, TU 14-1-4434-88, TU 14-1-565-84, TU 14-1-632-73, TU 14-1-685-88, TU 14-133-139-82, TU 14- 3-770-78, TU 14-1-3129-81 |
| Welding and cutting of metals. Soldering, riveting | B05 | OST 95 10441-2002, TU 14-1-656-73 |
| Thermal and thermochemical processing of metals | B04 | STP 26.260.484-2004, ST TsKBA 016-2005 |
| Sheets and strips | B53 | TU 1-9-1021-84, TU 1-9-1-84, TU 1-9-556-79, TU 1-9-1021-2008 |
| Metal mesh | B76 | TU 14-4-1569-89, TU 14-4-1561-89, TU 14-4-507-99 |
| Steel ropes | B75 | TU 14-4-278-73 |
Chemical composition
| Standard | C | S | P | Mn | Cr | Si | Ni | Fe | Cu | N | V | Mo | W | O |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| TU 1333-003-76886532-2014 | ≤0.12 | ≤0.02 | ≤0.035 | ≤2 | 17-19 | ≤0.8 | 9-11 | Remainder | ≤0.4 | - | ≤0.2 | ≤0.5 | ≤0.2 | - |
| TU 14-1-3844-84 | ≤0.12 | ≤0.02 | ≤0.035 | ≤2 | 17-19 | ≤0.8 | 10-11 | Remainder | ≤0.4 | - | ≤0.2 | ≤0.5 | ≤0.2 | - |
| TU 14-1-632-73 | 0.08-0.12 | ≤0.015 | ≤0.015 | 1-2 | 17-19 | ≤0.8 | 9-11 | Remainder | ≤0.25 | - | - | - | - | - |
| GOST 19277-73 | ≤0.12 | ≤0.015 | ≤0.015 | ≤2 | 17-19 | ≤0.8 | 9-11 | Remainder | ≤0.25 | - | - | - | - | - |
| TU 14-1-3581-83 | ≤0.12 | ≤0.02 | ≤0.03 | ≤2 | 17-19 | ≤0.8 | 9-11 | Remainder | ≤0.4 | - | ≤0.2 | ≤0.3 | ≤0.2 | - |
| TU 14-1-656-73 | ≤0.12 | ≤0.02 | ≤0.035 | 1-2 | 17-19 | ≤0.8 | 9-11 | Remainder | ≤0.4 | ≤0.02 | ≤0.2 | ≤0.5 | ≤0.2 | ≤0.006 |
| TU 14-1-748-73 | ≤0.12 | ≤0.02 | ≤0.04 | ≤2 | 17-19 | ≤0.8 | 9-11 | Remainder | ≤0.4 | - | ≤0.2 | ≤0.5 | ≤0.2 | - |
| TU 3-1002-77 | 0.09-0.12 | ≤0.02 | ≤0.035 | 1.5-2 | 17-18 | ≤0.8 | 10-11 | Remainder | ≤0.4 | - | ≤0.2 | ≤0.5 | ≤0.2 | - |
| TU 14-158-137-2003 | ≤0.12 | ≤0.02 | ≤0.035 | ≤2 | 17-19 | ≤0.8 | 9-11 | Remainder | - | - | - | - | - | - |
Fe- the basis.
According to GOST 5632-72, TU 108-930-80 and TU 14-1-748-73 Ti content % = 5C% - 0.8%. For aircraft parts, Mo content % ≤ 0.30%.
According to TU 14-1-2902-80 Ti content% = 5(C-0.02)% - 0.7%. At the request of the consumer, the Mn content can be set to ≤ 1.0%.
According to TU 14-1-2186-77 and TU 3-1002-77 Ti content % = 5(C-0.02) % - 0.7%.
According to TU 14-158-137-2003 Ti% content = 5C% - 0.7%. It is allowed to introduce cerium and other rare earth metals at a rate of 0.2-0.3%, which are not determined by chemical analysis.
According to TU 14-1-686-88, the chemical composition is given for steel 12Х18Н10Т-ВД. Ti% content = 5(C-0.2)% - 0.7%. Deviations from the content of elements in the chemical composition of steel, not established by technical specifications - in accordance with GOST 5632.
According to GOST 19277-73, the chemical composition is given for steel 12Х18Н10Т-ВД; steel grade 12Х18Н10Т must have a chemical composition in accordance with GOST 5632. Maximum deviations for the chemical composition are in accordance with GOST 5632. The mass fraction of titanium in steels 12Х18Н10Т and 12Х18Н10Т-VD should be Ti % = 5(С-0.02) % - 0 .7%.
According to TU 14-3R-115-2010, the mass fraction of titanium in steel 08Х18Н10Т should be Ti% = 5С% - 0.7%, but not less than 0.30%.
According to TU 14-1-3581-83, the chemical composition is given for steel 12Х18Н10Т-ВД. Ti% content = 5C% - 0.8%.
According to TU 14-1-632-73, the chemical composition is given for steel grade 12Х18Н10Т-ВД. Titanium content Ti = (C-0.02)x5%-0.7%. Deviations from the chemical composition standards are allowed in finished products: carbon -0.10%, manganese -0.30%, phosphorus +0.0050%.
Mechanical characteristics
| Section, mm | s T |s 0.2, MPa | σ B, MPa | d5,% | d 4 | d 10 | y, % | kJ/m 2, kJ/m 2 | Brinell hardness, MPa |
|---|---|---|---|---|---|---|---|---|
| Small-sized tubes (capillary) heat-treated or cold-worked as delivered according to GOST 14162-79 | ||||||||
| - | ≥549 | ≥35 | - | - | - | - | - | |
| Seamless pipes for oil and fuel lines, heat-treated as delivered according to GOST 19277-73 | ||||||||
| - | ≥549 | ≥40 | - | - | - | - | - | |
| - | 225-315 | 550-650 | 46-74 | - | - | 66-80 | 215-372 | - |
| Gradation of property indicators of finished heat-treated parts according to OST 1 90005-91 | ||||||||
| - | - | 540-800 | - | - | - | - | - | - |
| ≥246 | ≥520 | ≥37 | - | - | - | - | - | |
| Long products. Quenching 1050-1100 °C, air cooling | ||||||||
| - | 135-205 | 390-440 | 30-42 | - | - | 60-70 | 196-353 | - |
| Blanks (forgings and stampings) according to OST 95-29-72 in delivery condition: Austenization at 1020-1100 °C, cooling in water or air | ||||||||
| ≥186 | ≥372 | - | - | - | - | - | - | |
| Long products. Quenching 1050-1100 °C, air cooling | ||||||||
| - | 135-205 | 380-450 | 31-41 | - | - | 61-68 | 215-353 | - |
| ≤60 | ≥196 | ≥490 | ≥40 | - | - | ≥55 | - | 121-179 |
| Long products. Quenching 1050-1100 °C, air cooling | ||||||||
| - | 120-205 | 340-410 | 28-38 | - | - | 51-74 | 196-358 | - |
| Blanks for pipeline fittings according to ST TsKBA 016-2005. Hardening in water or in air from 1020-1100 °C (holding time 1.0-1.5 min/mm of largest cross-section but not less than 0.5 h) | ||||||||
| 60-100 | ≥196 | ≥490 | ≥39 | - | - | ≥50 | - | 121-179 |
| Long products. Quenching 1050-1100 °C, air cooling | ||||||||
| - | 120-195 | 270-390 | 27-37 | - | - | 52-73 | 245-353 | - |
| Blanks for pipeline fittings according to ST TsKBA 016-2005. Hardening in water or in air from 1020-1100 °C (holding time 1.0-1.5 min/mm of largest cross-section but not less than 0.5 h) | ||||||||
| 100-200 | ≥196 | ≥490 | ≥38 | - | - | ≥40 | - | 121-179 |
| Long products. Quenching 1050-1100 °C, air cooling | ||||||||
| - | 120-195 | 265-360 | 20-38 | - | - | 40-70 | 255-353 | - |
| Blanks for pipeline fittings according to ST TsKBA 016-2005. Hardening in water or in air from 1020-1100 °C (holding time 1.0-1.5 min/mm of largest cross-section but not less than 0.5 h) | ||||||||
| 200 | ≥196 | ≥490 | ≥35 | - | - | ≥40 | - | 121-179 |
| Solid rolled rings in delivery condition according to OST 1 90224-76. Hardening in air, oil or water from 1050-1100 °C | ||||||||
| ≥196 | ≥510 | ≥40 | - | - | ≥55 | - | - | |
| Cold-worked tape in accordance with TU 14-1-1073-74 | ||||||||
| - | - | ≥834 | - | ≥5 | - | - | - | - |
| Cold rolled strip 0.05-2.00 mm according to GOST 4986-79. Quenching in water or air from 1050-1080 °C (samples) | ||||||||
| 0.2-2 | - | ≥530 | - | ≥35 | - | - | - | - |
| 0.2 | - | ≥530 | - | ≥18 | - | - | - | - |
| Cold-rolled, heat-treated strip with an etched surface without tempering, as delivered according to TU 14-1-652-73 | ||||||||
| 0.1-0.8 | - | ≥529 | - | ≥35 | - | - | - | - |
| Hot rolled sheets (1.5-3.9 mm) and cold rolled sheets (0.7-3.9 mm) according to GOST 5582-75. No heat treatment | ||||||||
| ≤3.9 | - | 880-1080 | ≥10 | - | - | - | - | - |
| ≤3.9 | - | ≥740 | ≥25 | - | - | - | - | - |
| Hot rolled sheets (1.5-3.9 mm) and cold rolled sheets (0.7-3.9 mm) according to GOST 5582-75. Hardening in water or air from 1050-1080 °C | ||||||||
| - | ≥250 | ≥40 | - | - | - | - | - | |
| ≥205 | ≥530 | ≥40 | - | - | - | - | - | |
| Hot rolled sheets (4.0-50.0 mm) and cold rolled sheets (4.0-5.0 mm) according to GOST 7350-77. Hardening in water or air from 1000-1080 °C | ||||||||
| - | ≥235 | ≥530 | ≥38 | - | - | - | - | - |
| Cold-rolled sheets (0.7-5.0 mm) and hot-rolled sheets (3.0-6.0 mm) from steel 12Х18Н10Т in delivery condition according to TU 14-1-2476-78. Hardening in water or air from 1050-1080 °C | ||||||||
| - | - | ≥540 | ≥40 | - | - | - | - | - |
| Forgings for parts resistant to MCC. Quenching from 1000-1050 °C in oil, water or air | ||||||||
| 100-300 | ≥196 | ≥510 | ≥38 | - | - | ≥45 | - | 121-179 |
| 60-100 | ≥196 | ≥510 | ≥39 | - | - | ≥50 | - | 121-179 |
| 60 | ≥196 | ≥510 | ≥40 | - | - | ≥55 | - | 121-179 |
| Forgings. Quenching in water or air from 1050-1100 °C | ||||||||
| 1000 | ≥196 | ≥510 | ≥35 | - | - | ≥40 | - | - |
| Forgings. Quenching in air from 1050-1100 °C, cooling in oil or water | ||||||||
| ≥196 | ≥540 | ≥40 | - | - | ≥55 | - | - | |
| Spring wire of groups B (high-strength) and VO (high-strength for critical purposes) according to TU 3-1002-77. Hard-worked as delivered | ||||||||
| 0.11-0.71 | - | 1720-2010 | - | - | - | - | - | - |
| 0.81-2.81 | - | 1720-2010 | - | - | - | - | - | - |
| 3.01-3.51 | - | 1670-1960 | - | - | - | - | - | - |
| 4.01 | - | 1620-1910 | - | - | - | - | - | - |
| 4.51 | - | 1620-1860 | - | - | - | - | - | - |
| 5.01-5.51 | - | 1570-1760 | - | - | - | - | - | - |
| 6.01 | - | 1520-1720 | - | - | - | ≥20 | - | - |
| 6.51 | - | 1470-1670 | - | - | - | ≥20 | - | - |
| 7.01-7.51 | - | 1420-1620 | - | - | - | ≥20 | - | - |
| 8.01 | - | 1370-1570 | - | - | - | ≥20 | - | - |
| Spring wire of group N (normal strength) according to TU 3-1002-77. Hard-worked as delivered | ||||||||
| 0.51-6.01 | - | ≥1230 | - | - | - | - | - | - |
| 6.51-10.01 | - | - | - | - | - | - | - | - |
| Heat-treated wire as delivered in accordance with GOST 18143-72 (relative elongation, % with an estimated sample length of 100 mm is indicated for wire of the 1st class, in brackets - for the 2nd class) | ||||||||
| 0.2-1 | - | 590-880 | - | - | ≥25 (≥20) | - | - | - |
| 1.1-7.5 | - | 540-830 | - | - | ≥25 (≥20) | - | - | - |
| Cold-drawn wire as delivered in accordance with GOST 18143-72 | ||||||||
| 0.2-3 | - | 1130-1470 | - | - | - | - | - | - |
| 3.4-7.5 | - | 1080-1420 | - | - | - | - | - | - |
| Rolled products in as-delivered condition, without heat treatment | ||||||||
| ≤5 | - | ≥930 | - | - | - | - | - | - |
| - | - | ≥529 | ≥40 | - | - | - | - | - |
| - | - | ≥549 | ≥35 | - | - | - | - | - |
| Cold-rolled thin-sheet and heat-treated bent profiles in delivery condition in accordance with GOST R 51393-99. Hardening in water or air from 1050-1080 °C | ||||||||
| - | ≥205 | ≥530 | ≥40 | - | - | - | - | - |
| Hot rolled and forged rods according to TU 14-1-656-73. Longitudinal samples. Quenching in water from 1000-1050 °C | ||||||||
| - | ≥510 | ≥40 | - | - | ≥55 | - | - | |
| Bars calibrated as delivered (work-hardened) according to TU 14-1-3581-83 | ||||||||
| 20-25 | ≥225 | ≥539 | ≥25 | - | - | ≥55 | - | - |
| Rods according to TU 14-1-3581-83. Quenching in air, oil or water from 1050-1100 °C | ||||||||
| ≥196 | ≥539 | ≥40 | - | - | ≥55 | - | - | |
| Ground rods, processed to a specified strength (TS) according to GOST 18907-73 | ||||||||
| 1-30 | - | 590-830 | - | - | ≥20 | - | - | - |
| Hot-rolled and forged long products according to GOST 5949-75. Quenching in air, oil or water from 1020-1100 °C | ||||||||
| ≥196 | ≥510 | ≥40 | - | - | ≥55 | - | - | |
| Heat-treated thin sheet metal (softening) according to TU 14-1-3199-81 | ||||||||
| 0.5-3 | ≥274.4 | ≥549.8 | ≥40 | - | - | - | - | - |
| Pipe blank according to TU 14-1-686-88. Quenching in water or air from 1050-1080 °C | ||||||||
| - | ≥530 | ≥40 | - | - | - | - | - | |
| Heat-treated pipe blank according to TU 14-1-3844-84. Longitudinal and tangential samples | ||||||||
| - | ≥529 | ≥40 | - | - | - | - | - | |
| - | ≥510 | ≥40 | - | - | - | - | - | |
| Risk-free cold-deformed seamless pipes (cold-rolled, cold-drawn and warm-rolled) according to TU 14-3-769-78. Heat treated, as delivered | ||||||||
| ≥196 | ≥548.8 | ≥35 | - | - | - | - | - | |
| Seamless hot-deformed pipes as delivered in accordance with GOST 9940-81 | ||||||||
| - | ≥529 | ≥40 | - | - | - | - | - | |
| Seamless extra-thin-walled pipes with a diameter of up to 60 mm in a cold-worked state according to TU 14-3-770-78 | ||||||||
| ≥196 | ≥550 | ≥35 | - | - | - | - | - | |
| Seamless cold- and heat-deformed pipes of improved quality in delivery condition according to TU 14-3-1109-82 | ||||||||
| - | ≥558 | ≥36 | - | - | - | - | - | |
| Hexagonal heat-treated press-product pipes according to TU 14-131-880-97 | ||||||||
| ≥196 | ≥490 | ≥40 | - | - | ≥55 | - | - | |
| Heat-treated centrifugal cast pipes in the delivery condition according to TU 14-3R-115-2010. Quenching in water or in air under a fan at 1050-1080 °C | ||||||||
| ≥190 | ≥470 | ≥35 | - | - | - | - | - | |
| Heat-treated electric-welded pipes, as delivered (Dн=8.0-102.0 mm) | ||||||||
| ≥226 | ≥550 | ≥35 | - | - | - | - | - | |
| Stampings according to OST 1 90176-75. Quenching in air, oil or water from 1050-1100 °C | ||||||||
| ≥196 | ≥540 | ≥40 | - | - | ≥55 | - | - | |
Description of mechanical symbols
physical characteristics
| Temperature | E, GPa | G, GPa | r, kg/m3 | l, W/(m °С) | R, NOM m | a, 10-6 1/°С | C, J/(kg °C) |
|---|---|---|---|---|---|---|---|
| 20 | 198 | 77 | 7920 | 15 | 725 | - | - |
| 100 | 194 | 74 | - | 16 | 792 | 166 | 462 |
| 200 | 189 | 71 | - | 18 | 861 | 17 | 496 |
| 300 | 181 | 67 | - | 19 | 920 | 172 | 517 |
| 400 | 174 | 63 | - | 21 | 976 | 175 | 538 |
| 500 | 166 | 59 | - | 23 | 1028 | 179 | 550 |
| 600 | 157 | 57 | - | 25 | 1075 | 182 | 563 |
| 700 | 147 | 54 | - | 27 | 1115 | 186 | 575 |
| 800 | - | 49 | - | 26 | - | 189 | 575 |
| 900 | - | - | - | - | - | 189 | - |
| 1100 | - | - | - | - | - | 193 | - |
| 1000 | - | - | - | - | - | - | 596 |
Description of physical symbols
Technological properties
| Name | Meaning |
|---|---|
| Weldability | Weldable without restrictions. Welding methods: RDS (electrodes TsT-26), EShS and KTS. Subsequent heat treatment is recommended. For nuclear power plant equipment - automatic argon arc welding with a non-consumable electrode in a continuous mode, manual argon arc welding with a non-consumable electrode (with or without filler material), manual arc welding with coated electrodes is allowed. For manual arc welding, electrodes EA-400/10U are used; for automatic submerged arc - wire Sv04Х19Н11МЗ with OF-6 flux, wire Sv-08Х19Н10МЗБ with AN-26 flux; for welding in Ar shielding gas - welding wire Sv-04Х19Н11МЗ or Sv-08Х19Н10МЗБ. To prevent the tendency to knife corrosion of welded assemblies operating in nitric acid, welded assemblies are hardened in air from 970-1020 °C; in this case, the heating temperature should be kept at the upper limit (holding time for at least 2.5 min/mm of the largest wall thickness, but not less than 1 hour). In the case of welding with wire St. 04Х19Н11М3 or electrodes type E-07Х19Н11М3Г2Ф (grades EA-400/10U, EA-400/10T, wire St. 04Х19Н11М3, etc.), hardening in air from 950-1050 °C is used (holding time not less than 2 .5 min/mm of greatest wall thickness, but not less than 1 hour). In the case of welding with electrodes of type E-08Х19Н10Г2МБ (grades EA 898/21 B, etc.) to relieve residual stresses in welded assemblies: a) operating at temperatures of 350 °C and above; b) working at a temperature not higher than 350 °C, if hardening is not practical, use stabilizing annealing at 850-920 °C (holding time after heating the charge for at least 2 hours). To relieve residual stresses of welded assemblies operating at a temperature not exceeding 350 °C, after final mechanical treatment (before lapping), if other types of heat treatment are not practical, tempering at 375-400 °C (holding time 6-10 hours), air cooling is used . In the case of welding of pipes with an internal diameter of at least 100 mm or more to the body (without guy wire), according to the design documentation, stabilizing annealing at 950-970 °C and air cooling are used. |
| Forging temperature | Start - 1200 °C, end - 850 °C. Sections up to 350 mm are cooled in air. |
| Flock sensitivity | not sensitive. |
| Machinability | In the hardened state at НВ 169 and sВ=610 MPa Kn tv.all.=0.85 Kn b.st.=0.35. |
| Macrostructure and contamination | The macrostructure of the steel should be free of traces of shrinkage cavities, delaminations, and foreign inclusions. The macrostructure of steel according to TU 14-1-686-88 should not have shrinkage, looseness, bubbles, cracks, foreign inclusions, crusts, delaminations and flakes visible without the use of magnifying devices. In terms of central porosity, point heterogeneity and segregation square, macrostructural defects should not exceed score I for each type. The presence of layer-by-layer crystallization and a light contour in the macrostructure of the metal is not a rejection sign. The content of non-metallic inclusions in steel, according to the maximum score, should not exceed: oxides and silicates (OT, OS, CX, SP, CH) - 2 points; sulfide (C) - 1 point; titanium nitrides and carbonitrides (NT) - 4.5 points. |
| Microstructure | The content of the ferrite phase (alpha phase) in rods with a diameter or square side of 80 mm or more should not exceed 1.5 points (4-5%). Rods with a diameter or side less than 80 mm and strips are not subjected to determination of the ferrite phase. |
| Features of heat treatment | Depending on the purpose, operating conditions, and aggressiveness of the environment, the products are subjected to: a) hardening (austenitization); b) stabilizing annealing; c) annealing to relieve stress; d) stepwise processing. Products are hardened in order to: a) prevent the tendency to intergranular corrosion (products operate at temperatures up to 350 ° C); b) increase resistance to general corrosion; c) eliminate the identified tendency to intergranular corrosion; d) prevent the tendency to knife corrosion (welded products work in nitric acid solutions); e) eliminate residual stresses (products of simple configuration); e) increase the ductility of the material. Hardening of products must be carried out according to the following regime: heating to 1050-1100 °C, parts with a material thickness of up to 10 mm should be cooled in air, over 10 mm - in water. Welded products of complex configuration should be cooled in air to avoid leakage. The holding time when heating for hardening for products with a wall thickness of up to 10 mm is 30 minutes, over 10 mm - 20 minutes + 1 minute per 1 mm of maximum thickness. When hardening products intended to work in nitric acid, the heating temperature for hardening must be kept at the upper limit (the holding time for welded products must be at least 1 hour). Stabilizing annealing is used to: a) prevent the tendency to intergranular corrosion (products operate at temperatures above 350 °C); b) relieving internal stress; c) eliminating the detected tendency to intergranular corrosion, if for some reason hardening is impractical. Stabilizing annealing is permissible for products and welded joints made of steels with a titanium to carbon ratio of more than 5 or niobium to carbon of more than 8. To prevent the tendency to intergranular corrosion of products operating at temperatures above 350 ° C, stabilizing annealing can be applied to steel containing more than 0.08% carbon. Stabilizing annealing should be carried out according to the following regime: heating to 870-900 °C, holding for 2-3 hours, cooling in air. When heat treating large-sized welded products, it is allowed to carry out local stabilizing annealing of the closing seams according to the same regime, and all welded elements must be subjected to stabilizing annealing before welding. When carrying out local stabilizing annealing, it is necessary to ensure simultaneous uniform heating and cooling along the entire length of the weld and adjacent zones of the base metal to a width equal to two to three times the width of the weld, but not more than 200 mm. Manual heating is not acceptable. To more completely remove residual stresses, annealing of products made of stabilized chromium-nickel steels is carried out according to the following regime: heating to 870-900 °C; holding for 2-3 hours, cooling with a furnace to 300 °C (cooling rate 50-100 °C/h), then in air. Annealing is carried out for products and welded joints made of steel in which the ratio of titanium to carbon is more than 5 or niobium to carbon is more than 8. Stepwise processing is carried out to: a) relieve residual stresses and prevent the tendency to intergranular corrosion; b) to prevent the tendency to intergranular corrosion of welded joints of complex configuration with sharp transitions in thickness; c) products with a tendency to intergranular corrosion, which cannot be eliminated by any other method (quenching or stabilizing annealing). Stepwise processing must be carried out according to the following mode: heating to 1050-1100 °C; holding time when heating for hardening for products with a wall thickness of up to 10 mm - 30 minutes, over 10 mm - 20 minutes + 1 minute per 1 mm of maximum thickness; cooling at the highest possible speed up to 870-900°C; exposure at 870-900 °C for 2-3 hours; cooling with a furnace to 300 °C (speed - 50-100 °C/h), then in air. To speed up the process, stepwise processing is recommended to be carried out in two-chamber or two furnaces heated to different temperatures. When transferring from one oven to another, the temperature of the products should not be lower than 900 °C. Step processing is permitted for products and welded joints made of steel with a titanium to carbon ratio of more than 5 or niobium to carbon of more than 8. |
| Corrosion resistance | The steel is resistant to intergranular corrosion. The steel is unstable in sulfur-containing environments and is used when nickel-free steels cannot be used. The steel should not be prone to intergranular corrosion. |
For the manufacture of welded structures using cryogenic technology at temperatures down to -269 °C.
Steel is smelted in electric arc furnaces.
GOST standards and specifications for steel 12Х18Н10Т
GOST 1133-71 "Forged steel round and square. Assortment";GOST 18143-72 "Wire made of high-alloy corrosion-resistant and heat-resistant steel. Technical conditions.";
GOST 18907-73 "Work-worked, heat-treated, ground rods made of high-alloy and corrosion-resistant steel. Technical conditions.";
GOST 25054-81 "Forgings made of corrosion-resistant steels and alloys. General technical conditions.";
GOST 4986-79 "Cold-rolled strip made of corrosion-resistant and heat-resistant steel. Technical conditions";
GOST 5582-75 "Corrosion-resistant, heat-resistant and heat-resistant rolled thin sheets. Technical conditions";
GOST 5632-72 "High-alloy steels and corrosion-resistant, heat-resistant and heat-resistant alloys. Grades";
GOST 5949-75 "Grade and calibrated steel, corrosion-resistant, heat-resistant and heat-resistant. Technical conditions";
GOST 7350-77 "Corrosion-resistant, heat-resistant and heat-resistant thick sheet steel. Technical conditions";
GOST 9940-81 "Hot-deformed seamless pipes made of corrosion-resistant steel. Technical conditions";
GOST 9941-81 "Cold- and heat-deformed seamless pipes made of corrosion-resistant steel. Technical conditions";
GOST 14955-77 "High-quality round steel with special surface finishing. Technical conditions.";
GOST 2590-2006 "High-rolled round steel products. Assortment.";
GOST 7417-75 "Calibrated round steel. Assortment.";
GOST 8559-75 "Square calibrated steel. Assortment.";
GOST 8560-78 "Calibrated hexagonal rolled products. Assortment.";
GOST 1133-71 "Forged steel round and square. Assortment.";
GOST 5632-72 "High-alloy steels and corrosion-resistant, heat-resistant and heat-resistant alloys. Grades.";
GOST 5949-75 "High grade and calibrated steel, corrosion-resistant, heat-resistant and heat-resistant. Technical conditions.";
GOST 2879-2006 "Hot-rolled hexagonal steel bars. Assortment.";
TU 14-11-245-88 "High precision shaped steel profiles. Technical conditions.";
OST 3-1686-90 "Structural steel blanks for mechanical engineering. General technical conditions.";
Chemical composition of steel 12Х18Н10Т
| C | Cr | Fe | Mn | Ni | P | S | Si | Ti |
| ≤0,12 | 17-19,0 | Basic | ≤2,0 | 9-11,0 | ≤0,035 | ≤0,020 | ≤0,8 | 5·С-0.8 |
Mechanical properties of steel 12Х18Н10Т
Normalized mechanical properties of steels at 20 °C
GOST | Product type | σ in , N/mm² | σ 0.2, N/mm² | δ5,% | |||||||||||
Soft tape | |||||||||||||||
Hot deformed | Cold-worked | Wire | |||||||||||||
Note. In case of differences in properties, the properties of steel 12Х18Н9Т are indicated in parentheses. |
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Mechanical properties of steel 12Х18Н9Т at low and elevated temperatures (rod Ø18-25 mm, quenching at 1050 °C in water)
t isp, °С | σ in , N/mm² | σ 0.2, N/mm² | δ5,% | KCU, J/cm 2 |
|
Mechanical properties of steel 12Х18Н9Т at high temperatures
t isp, °С | σ in , N/mm² | δ5,% | KCU, J/cm 2 | n, about |
|
Note. In the numerator - the content of 6-ferrite in the structure after heat treatment |
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Mechanical properties of steel 12Х18Н10Т depending on the degree of cold deformation (sheet, initial heat treatment: quenching at 1050 °C in water)
Compression degree, % | σ in , N/mm² | σ 0.2, N/mm² | δ5,% | Compression degree, % | σ in , N/mm² | σ 0.2, N/mm² | δ5,% |
Note. In the numerator - test temperature -20 °C; the denominator is -253 °C. |
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Physical properties of steel 12Х18Н10Т
Density - 7.9 · 10³ kg/m³.
Elastic modulus - 18 10 4 N/mm 2 at 20 °C.
Electrical resistivity - 0.75 10 6, Ohm m at 20 °C.
Properties of steels at low, elevated and high temperatures
t isp, °С | E 10 -4 N/mm 2 | λ, W/(m K) | ρ ·10 6 , Ohm · m | s, J/(kg K) |
Temperature coefficient of linear expansion value
t, °С | 23-20, GOST 5582-84, GOST 4986-78, GOST 5945-75, Steels 12Х18Н10Т and 12Х18Н9Т have fairly high heat resistance at 600-800 °C. Technological parameters 12Х18Н10ТSteels 12Х18Н10Т and 12Х18Н9Т have good processability during hot plastic deformation. However, when hot working, it is necessary to take into account the specific chemical composition of a given melt, bearing in mind the content of 8-ferrite. Special precautions should be taken when deforming cast metal. In order to avoid the formation of irreparable defects - flaws, it is recommended to heat ingots of steels 12Х18Н10Т and 12Х18Н9Т with a content of 20% 8-ferrite or more no higher than 1240-1250 °C, with a content of 16-19% - no higher than 1255 °C and with a content of up to 16% - up to 1270 °C. The temperature range for pressure treatment of deformed metal is 1180-850 °C. The heating and cooling speed is not limited.When cold, both steels allow high degrees of plastic deformation. To relieve stress and improve the durability of welded joints, in addition to hardening, welded structures are subjected to stabilizing annealing at 850-900°C. Welding steel 12Х18Н10ТSteels 12Х18Н10Т and 12Х18Н9Т can be welded well by all types of manual and automatic welding. For conventional automatic submerged arc welding AN-26, AN-18 and argon arc welding, wire Sv-08Kh19N10B, Sv-04Kh22N10BT, Sv-05Kh20N9FBS and Sv-06Kh21N7BT are used, and for manual - electrodes type EA-1F2 grades GL-2, TsL- 2B2, EA-606/11 with wire Sv-05Х19Н9ФЗС2, Sv-08Х19Н9Ф2С2 and Sv-05Х19Н9ФЗС2. Wire Sv-08Х20Н9С2БТУ is recommended for manual automatic welding in shielding gas.For manual electric arc welding, electrodes TsL-11 and TsL-9 with electrode rod material Sv-07X19N10B and Sv-07X25N13, respectively, can also be used. Both types of electrode ensure resistance of the weld metal against intergranular corrosion when tested according to the AM and AMU methods of GOST 6032-89 without provoking heating. Welded joints obtained using TsL-11 and TsL-9 electrodes have the following mechanical properties (at least): σ in = 550 and 600 N/mm 2, δ = 22 and 25%, KCU = 80 and 70 J/ cm 2. The use of these welding materials provides high corrosion resistance to general and intergranular corrosion in 65% nitric acid at 70-80 °C. However, welded joints of steels 12Х18Н10Т and 12Х18Н9Т may exhibit a tendency to knife corrosion in this environment. © Use of materials from the site is possible only with the permission of LASMET LLC |
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PeculiaritiesAndcharacteristicssteel 12Х18Н10Т
The modern development of mankind is inextricably linked with the development of new technologies, the creation of new materials for use in various industries and extending the service life of created parts, machines and equipment.
One of the most important stages in the development of metallurgy was the creation and development of stainless steels. Let's consider the most used and widespread steel 12Х18Н10Т - we will identify the advantages, disadvantages, the influence of alloying elements on the properties of steel and the possibility of using it in various industries.
Chemical composition
Steel 12x18n10t - stainless titanium-containing steel of the austenitic class (determined according to the Scheffler diagram, Fig. 1). The chemical composition is regulated by GOST 5632-72 of austenitic stainless steels. Advantages: high ductility and impact strength.
Picture 1.
The optimal heat treatment for these steels is quenching from 1050 o C-1080 o C in H2O; after quenching, the mechanical properties are characterized by maximum toughness and ductility, not high strength and hardness.
Heat treatment of steel is necessary in order to give the material certain properties. For example, increased ductility, wear resistance, increased hardness or durability. Can boast of all these qualities sheet 12x18n10t.
The heat treatment process can be divided into four types:
1. Annealing. This heat treatment process allows you to achieve a uniform structure. Annealing takes place in three stages: the steel is heated to a certain temperature, then held at a certain temperature, and then slowly cooled in a furnace. A uniform structure is obtained only during second-order annealing; during first-order, no structural changes occur.
2. Hardening. This type of heat treatment allows you to create steel with a variety of structures and properties. The entire technological process takes place in three stages: at a certain specified temperature, the steel is heated, then it is held at the same temperature and, in contrast to annealing, rapid cooling occurs.
3. Vacation. This heat treatment technology is used to reduce the internal stress of the material.
4. Normalization. This type of heat treatment is also carried out in three stages: heating, holding and cooling. The temperature is set for the first two stages, and the third stage is carried out in air.
To get a high-quality 12x18n10t sheet, you need to carry out the heat treatment process correctly. First of all, attention is paid to the properties of steel, namely its operational and technological characteristics. They are most important in the manufacture of certain parts and products, such as 12x18n10t sheet. Taking into account the steel grade, the hardening process takes place in the temperature range of 530-1300°C. Through heat treatment, the structure of the metal can be significantly changed.
Mechanical properties
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Heat treatment, delivery condition |
Section, mm |
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Rods. Tempered at 1020-1100 °C, air, oil or water. |
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The rods are ground and processed to a specified strength. |
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Cold-worked rods |
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Sheets are hot-rolled or cold-rolled. Quenching 1000-1080 °C, water or air. |
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Sheets are hot-rolled or cold-rolled. Quenching 1050-1080 °C, water or air. |
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Hot-rolled or cold-rolled cold-worked sheets |
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Forgings. Quenching 1050-1100 °C, water or air. |
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Heat treated wire |
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Seamless hot-deformed pipes without heat treatment. |
Mechanical properties at elevated temperatures
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t test, °C |
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Austenitic steels are used as heat-resistant steels at temperatures up to 600 o C. The main alloying elements are Cr-Ni. Single-phase steels have a stable structure of homogeneous austenite with a small content of Ti carbides (to prevent intergranular corrosion. This structure is obtained after hardening from temperatures of 1050 o C-1080 o C). Steels of austenitic and austenitic-ferritic classes have a relatively low level of strength (700-850MPa).
Let us consider the features of the influence of alloying elements on the structure of steel 12Х18Н10Т.
Chromium, the content of which in this steel is 17-19%, is the main element that ensures the metal's ability to passivate and ensures its high corrosion resistance. Alloying with nickel transfers steel to the austenitic class, which is of fundamental importance, since it allows you to combine the high manufacturability of steel with a unique set of performance characteristics. In the presence of 0.1% carbon, steel has a completely austenitic structure at >900 o C, which is associated with the strong austenite-forming effect of carbon. The ratio of chromium and nickel concentrations has a specific effect on the stability of austenite when the processing temperature is cooled to a solid solution (1050-1100 o C). In addition to the influence of the main elements, it is also necessary to take into account the presence of silicon, titanium and aluminum in the steel, which contribute to the formation of ferrite.
Let's consider methods of hardening steel 12Х18Н10Т.
One of the ways to harden long products is High Temperature Heat Treatment (HTHT). The possibilities of hardening using HTMT were studied on a combined semi-continuous mill 350 of the Kirov Plant production association. The blanks (100x100 mm, 2.5 - 5 m long) were heated in a methodical oven to 1150 - 1200 o C and kept at these temperatures for 2-3 hours. Rolling was performed using conventional technology; finished rods with a diameter of 34 mm entered quenching baths filled with running water, where they were cooled for at least 90 s. The greatest strength was found in rolled products subjected to HTMT at the lowest deformation temperature and time interval from the end of rolling to quenching. Thus, with HTMT of steel 08Х18Н10Т, the yield strength increased by 45-60% compared to its level after conventional heat treatment (OTT) and 1.7-2 times compared to GOST 5949-75; At the same time, the plastic properties decreased slightly and remained at the level of the standard requirements.
Stainless steel 12Х18Н10Т was strengthened more than steel 08Х18Н10Т; however, softening as the temperature increased increased to a greater extent due to a decrease in the steel’s resistance to softening with increasing carbon content. Short-term high-temperature tests have shown that the higher level of strength of thermomechanically strengthened rolled products, revealed at room temperature, is maintained at elevated temperatures. In this case, steel after HTMT softens with increasing temperature, to a lesser extent than steel after HTMT.
Chromium-nickel stainless steels are used for welded structures in cryogenic technology at temperatures down to -269 o C, for capacitive, heat exchange and reaction equipment, including steam heaters and high-pressure pipelines with operating temperatures up to 600 o C, for parts of furnace equipment, muffles, exhaust system manifolds. The maximum temperature for using heat-resistant products made from these steels for 10,000 hours is 800 o C, the temperature at which intense scaling begins is 850 o C. During continuous operation, the steel is resistant to oxidation in air and in the atmosphere of fuel combustion products at temperatures<900 о С и в условиях теплосмен <800 о С.
Corrosion-resistant steel 12Х18Н10Т is used for the manufacture of welded equipment in various industries, as well as structures operating in contact with nitric acid and other oxidizing environments, some organic acids of medium concentration, organic solvents, in atmospheric conditions, etc. Steel 08Х18Н10Т is recommended for welded products operating in environments of higher aggressiveness than steel 12Х18Н10Т and has increased resistance to intergranular corrosion.
Thus, thanks to the unique combination of properties and strength characteristics, stainless steel 12Х18Н10Т has found the widest application in almost all industries; products made from this steel have a long service life and consistently high performance throughout their entire service life.
Welding steel 12Х18Н10Т
Steel welding is the main technological process of almost any production of metal products. From the 7th century BC to the present day, welding has been widely used as the main method of forming permanent metal joints. From its inception until the 19th century AD. The method of forge welding of metals was used. Those. the parts to be welded were heated and then pressed together with hammer blows. This technology reached its peak by the middle of the 19th century, when it began to be used to manufacture even such critical products as railway rails and main pipelines.
However, welded joints, especially on a mass industrial scale, were characterized by low reliability and unstable quality. This often led to accidents due to the destruction of the part at the weld.
The discovery of electric arc heating and high-temperature gas-oxygen combustion, along with increased requirements for the quality of the welded joint, made a powerful technological breakthrough in the field of welding, resulting in the creation of forgeless welding technology - the kind that we are accustomed to seeing today.
With the advent of alloy steel, welding processes became more complicated due to the need to prevent carbidation of alloying elements, mainly chromium. Methods of welding in inert environments or submerged arcs, as well as technologies for additional alloying of the weld, have appeared.
Let us consider the features of welding austenitic steels based on the most common stainless steel 12Х18Н10Т.
Steel 12Х18Н10Т treat well weldable. A characteristic feature of welding this steel is the occurrence of intergranular corrosion. It develops in the heat-affected zone at a temperature of 500-800?C. When the metal remains in such a critical temperature range, chromium carbides precipitate along the boundaries of austenite grains. All this can have dangerous consequences - brittle destruction of the structure during operation. steel chemical composition welding
To achieve durability of steel, it is necessary to eliminate or reduce the effect of carbide precipitation and stabilize the properties of steel at the weld site.
When welding high-alloy steels, electrodes with a protective alloying coating of the basic type are used in combination with a high-alloy electrode rod. The use of electrodes with a basic type of coating makes it possible to ensure the formation of the deposited metal of the required chemical composition, as well as other properties, through the use of highly alloyed electrode wire and additional alloying through the coating.
The combination of alloying through the electrode wire and coating makes it possible to provide not only a guaranteed chemical composition within the passport data, but also some other properties intended for welding austenitic steels 12Х18Н10Т, 12Х18Н9Т, 12Х18Н12Т and the like.
Submerged arc welding of high-alloy steels is carried out using either oxygen-neutral fluoride fluxes or protective alloying ones in combination with high-alloy electrode wire. From a metallurgical point of view, the most rational for welding high-alloy steels are fluoride fluxes of the ANF-5 type, which provide good protection and metallurgical processing of the weld pool metal and allow the weld pool to be alloyed with titanium through the electrode wire. At the same time, the welding process is insensitive to the formation of pores in the weld metal due to hydrogen. However, fluoride oxygen-free fluxes have relatively low technological properties. It is the low technological properties of fluoride fluxes that are the reason for the widespread use of oxide-based fluxes for welding high-alloy steels.
To reduce the likelihood of the formation of an overheating structure, welding of high-alloy steels is usually performed in modes characterized by a low heat input. In this case, preference is given to seams of small cross-section, obtained using electrode wire of small diameter (2-3 mm). Since high-alloy steels have increased electrical resistance and reduced electrical conductivity, during welding the stickout of an electrode from high-alloy steel is reduced by 1.5-2 times compared to the stickout of an electrode from carbon steel.
When arc welding, argon, helium (less commonly), and carbon dioxide are used as shielding gases.
Argon arc welding is performed with consumable and non-consumable tungsten electrodes. A consumable electrode is welded using direct current of reverse polarity, using modes that ensure jet transfer of the electrode metal. In some cases (mainly when welding austenitic steels), to increase the stability of the arc and especially reduce the likelihood of pore formation due to hydrogen when welding with a consumable electrode, mixtures of argon with oxygen or carbon dioxide (up to 10%) are used.
Welding with a non-consumable tungsten electrode is mainly carried out using direct current of straight polarity. In some cases, when steel contains a significant amount of aluminum, alternating current is used to ensure cathodic destruction of the oxide film.
The use of arc welding in a carbon dioxide atmosphere reduces the likelihood of pores forming in the weld metal due to hydrogen; this ensures a relatively high transition coefficient of easily oxidized elements. Thus, the transfer coefficient of titanium from wire reaches 50%. When welding in an argon atmosphere, the transfer coefficient of titanium from wire is 80-90%. When welding steels with a high chromium content and low silicon content in carbon dioxide, a refractory, difficult-to-remove oxide film is formed on the surface of the weld. Its presence makes multilayer welding difficult.
When welding steels with low carbon content (below 0.07-0.08%), carburization of the deposited metal is possible. The transition of carbon into the weld pool is enhanced by the presence of aluminum, titanium, and silicon in the electrode wire. In the case of welding deep austenitic steels, some carburization of the weld pool metal in combination with oxidation of silicon reduces the likelihood of hot cracking. However, carburization can change the properties of the weld metal and, in particular, reduce the corrosion properties. In addition, increased spattering of the electrode metal is observed. The presence of splashes on the metal surface reduces corrosion resistance.
Welding technologies for stainless high-alloy steels are constantly being improved. At this stage, with strict adherence to the technological process, the quality of the stainless steel weld is practically not inferior in its properties to the metal of the parts being connected and guarantees the highest reliability of the welded joint.
Education Defectoin welded joints during welding
When fusion welding, the most common defects of welded joints are incompleteness of the weld, uneven width and height (Fig. 1), large scaliness, tuberosity, and the presence of saddles. In automatic welding, defects arise due to voltage fluctuations in the network, wire slipping in the feed rollers, uneven welding speed due to backlash in the movement mechanism, incorrect angle of inclination of the electrode, and flow of liquid metal into the gap. In manual and semi-automatic welding, defects can be caused by insufficient qualifications of the welder, violation of technological methods, poor quality of electrodes and other welding materials.
Rice. 2. Defects in the shape and size of the seam: a - incompleteness of the seam; b - uneven width of the butt weld; c - unevenness along the length of the fillet weld leg; h - required seam reinforcement height
For pressure welding (for example, spot welding), characteristic defects are uneven spacing of points, deep dents, and displacement of the axes of the joined parts.
Violation of the shape and size of the seam often indicates the presence of defects such as sagging (sagging), undercuts, burns and uncertified craters.
Surges(sagging) (Fig. 2) are most often formed when welding vertical surfaces with horizontal seams as a result of liquid metal flowing onto the edges of the cold base metal. They can be local, in the form of individual frozen drops, or have a significant extent along the seam. The reasons for the occurrence of sagging are: a large welding current, a long arc, incorrect position of the electrode, a large angle of inclination of the product when welding up and down. In circumferential welds, sagging is formed when the electrode is insufficiently or excessively displaced from the zenith. Lack of penetration, cracks and other defects are often detected in places where there are leaks.
Undercuts are depressions (grooves) formed in the base metal along the edge of the seam with an increased welding current and a long arc, since in this case the width of the seam increases and the edges melt more strongly. When welding with fillet welds, undercuts occur mainly due to the displacement of the electrode towards the vertical wall, which causes significant heating, melting and flow of its metal onto the horizontal shelf. As a result, undercuts appear on the vertical wall, and sagging appears on the horizontal shelf. In gas welding, undercuts are formed due to the increased power of the welding torch, and in electroslag welding - due to improper installation of the forming slides.
Undercuts lead to a weakening of the base metal section and can cause destruction of the welded joint.
Fig3. External defects: a - butt; b - corner; 1 - influx; 2 - undercut.
Burns- This is the penetration of the base or deposited metal with the possible formation of through holes. They arise due to insufficient blunting of the edges, a large gap between them, excessive welding current or torch power at low welding speeds. Burn-throughs are especially common during welding of thin metal and when performing the first pass of a multi-layer weld. In addition, burns can occur as a result of poor compression of the flux pad or copper pad (automatic welding), as well as with increased welding duration, low compression force and the presence of contamination on the surfaces of the parts being welded or electrodes (spot and seam resistance welding).
Unfilled craters are formed in the event of a sudden break in the arc at the end of welding. They reduce the cross-section of the seam and can become sources of crack formation.
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