CN113235006A - Method for producing low-carbon austenitic stainless steel bar by reducing load of rolling mill - Google Patents
Method for producing low-carbon austenitic stainless steel bar by reducing load of rolling mill Download PDFInfo
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- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
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- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
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- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
- B22D11/001—Continuous casting of metals, i.e. casting in indefinite lengths of specific alloys
- B22D11/002—Stainless steels
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- B22—CASTING; POWDER METALLURGY
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- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
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- B22D11/22—Controlling or regulating processes or operations for cooling cast stock or mould
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- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
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- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/70—Furnaces for ingots, i.e. soaking pits
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- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
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- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/42—Ferrous alloys, e.g. steel alloys containing chromium with nickel with copper
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- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
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- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/44—Ferrous alloys, e.g. steel alloys containing chromium with nickel with molybdenum or tungsten
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- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
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Abstract
The invention discloses a method for producing a low-carbon austenitic stainless steel bar by reducing the load of a rolling mill, and particularly relates to the technical field of metal pressure processing, which comprises the following steps: determining chemical components of the low-carbon austenitic stainless steel according to national standard requirements; step two, a certain amount of Cu element is generally added to the low-carbon austenitic stainless steel rod to ensure the subsequent perforation or machining, if Cu is more than or equal to 0.35 percent, S is ensured to be less than or equal to 0.0015 percent, and the formation of a low-melting-point compound CuS is avoided; determining the in-furnace time according to the cold blank or the hot blank of the continuous casting blank and the section size of the continuous casting blank before rolling; step four, smelting and continuous casting; step five, heating the furnace: controlling the atmosphere and air quantity in the heating furnace; step six, rolling: the rolling mill is used for rolling according to the conventional operation, the current of the motor is observed, when the load reaches 90% of the rated load, the temperature of the heating furnace is adjusted and raised in time or the furnace time is prolonged properly, and the phenomenon that the load exceeds 90% of the rated load is determined to be avoided. The invention improves the high-temperature plasticity of the low-carbon austenitic stainless steel by controlling De-f, organizes production under the condition of reducing the load of a rolling mill, improves the yield and the qualification rate, and simultaneously prolongs the service life of steel rolling equipment.
Description
Technical Field
The embodiment of the invention relates to the technical field of metal pressure processing, in particular to a method for producing a low-carbon austenitic stainless steel bar by reducing the load of a rolling mill.
Background
The austenitic stainless steel is a stainless steel having an austenitic structure at normal temperature. The steel has a stable austenitic structure when it contains about 18% Cr, 8% to 25% Ni, and about 0.1% C. The austenitic chromium-nickel stainless steel comprises typical 18Cr-8Ni steel and high Cr-Ni series steel developed by increasing the content of Cr and Ni and adding elements such as Mo, Cu, Si, Nb, Ti and the like. Austenitic stainless steel is nonmagnetic and has high toughness and plasticity, but has low strength, cannot be strengthened by phase transformation, can be strengthened only by cold working, and has good free-cutting property if elements such as S, Ca, Se, Te and the like are added.
The low-carbon austenitic stainless steel has low carbon content, forms few Cr carbides, greatly improves the corrosion resistance of the stainless steel, and common steel grades comprise 304L, 316L and the like. In the hot rolling production process, the low-carbon austenitic stainless steel is easy to crack in different degrees, particularly the low-carbon austenitic stainless steel has low thermoplasticity in high-temperature production, and the cracking probability is improved. Most low-carbon austenitic stainless steel has better thermoplasticity at about 1120 ℃, so the cracking problem can be improved to a certain extent by reducing the temperature for rolling, but the deformation resistance of the stainless steel is increased along with the reduction of the temperature, the load of a rolling mill is increased, and the service life of equipment is influenced to a certain extent by frequent overload operation, such as the frequent accidents of shaft breakage of a speed reducer and the like. Analysis of low carbon austenitic stainless steel materials has found that when a certain amount of ferrite is contained, the high temperature plasticity can be improved properly, because the orientation of the dendrites of the cast slab can be disturbed by keeping a certain amount of ferrite, so that the columnar grains of the austenite are prevented from being coarse, and eutectic substances are prevented from being concentrated on fewer grain boundaries. Ferrite dissolves more harmful impurities than austenite, such as S, P, etc., and thus the inclusion of a certain amount of ferrite reduces the risk of rolling cracking. Meanwhile, a certain amount of ferrite can be kept to effectively improve the intergranular corrosion resistance of the low-carbon austenitic stainless steel. At present, there is a paper that the rolling defects can be improved by controlling the ferrite content in austenitic stainless steel, but the ferrite content data is not specifically indicated.
Disclosure of Invention
Therefore, the embodiment of the invention provides a method for producing a low-carbon austenitic stainless steel bar by reducing the load of a rolling mill, which improves the high-temperature plasticity of the low-carbon austenitic stainless steel by controlling the De-f value of the low-carbon austenitic stainless steel, organizes the production under the condition of reducing the load of the rolling mill, improves the yield and the qualification rate, and simultaneously improves the service life of steel rolling equipment so as to solve the problems of large load of the rolling mill and low yield caused by the increase of the deformation resistance of the stainless steel due to the reduction of the temperature in the prior art.
In order to achieve the above object, the embodiments of the present invention provide the following technical solutions: a method for producing low-carbon austenitic stainless steel rods by reducing the load of a rolling mill comprises the following steps:
step one, determining chemical components of the low-carbon austenitic stainless steel according to national standard requirements: 0.025% of C, 0.50% of Si, 0.90% of Mn, 0.04% of P, 0.002% of S, 16.14% of Cr, 10.02% of Ni, 2.04% of Mo, 0.31% of Cu, 0.001% of Ti and 0.039% of N, and calculating to obtain De-f which is 4.06%;
step two, adding a certain amount of Cu element to the low-carbon austenitic stainless steel rod in order to ensure subsequent perforation or machining, and if Cu is more than or equal to 0.35%, ensuring that S is less than or equal to 0.0015% and avoiding the formation of a low-melting-point compound CuS;
determining the in-furnace time before rolling according to whether the continuous casting billet is a cold billet or a hot billet and the section size of the continuous casting billet, wherein the in-furnace time of the hot billet of the continuous casting billet with the section of 180 multiplied by 180 mm-200 multiplied by 200mm is generally 120-150 min, and the in-furnace time of the cold billet of the continuous casting billet with the section of 180 multiplied by 180 mm-200 multiplied by 200mm is generally 180-210 min;
step four, smelting and continuous casting: the surface quality and the macroscopic structure of the continuous casting billet are controlled by measures such as cooling water, covering slag and the like, the defects such as surface cracks, scabs and the like are ensured to be avoided, and the macroscopic defect level such as center porosity, center segregation, shrinkage cavity and the like is less than or equal to 1.5 level;
step five, heating the furnace: controlling the atmosphere and the air quantity in the heating furnace, ensuring that the fuel is fully combusted, and preventing the furnace from generating obvious oxidizing atmosphere, wherein the air-coal ratio of a heating section and a soaking section is set to be 0.7-0.9, the furnace is in a micro-positive pressure state, the temperature of a preheating section is kept in a conventional process, the temperature of the heating section and the soaking section is increased by 20-40 ℃, the furnace time of a hot blank is 120-150 min, and the furnace time of a cold blank is 180-210 min;
step six, rolling: rolling by using a rolling mill according to conventional operation, observing the current of a motor, adjusting and raising the temperature of a heating furnace in time or properly prolonging the furnace time when the load reaches 90% of the rated load, determining that the phenomenon of exceeding 90% of the rated load does not exist, and controlling the De-f value to be within the range of 3% -5%.
Further, in the step one, the calculation of De-f is represented by the following formula
Further, in the step one, the content of each element component can be properly adjusted according to the production stability condition, but the corresponding standard is ensured to be met and the De-f value is ensured to be in the range of 3-5%.
Further, in step one, the national standard requirement of the low carbon austenitic stainless steel 316L is as follows: less than or equal to 0.03 percent of C, less than or equal to 1.0 percent of Si, less than or equal to 2.0 percent of Mn, less than or equal to 0.045 percent of P, less than or equal to 0.030 percent of S, 16.00 to 18.00 percent of Cr16, 10.00 to 14.00 percent of Nis and 2.00 to 3.00 percent of Mos.
Further, in the fifth step, the preheating section is less than or equal to 980 ℃, the heating section is 1200 ℃, the soaking section is 1220 ℃, the cold charge is carried out in the furnace, the furnace time is 200min, the empty coal ratio of the heating section and the soaking section is set to be 0.85, the pressure in the furnace is 25Pa, and the temperature fluctuation is controlled to be within +/-10 ℃.
The embodiment of the invention has the following advantages:
1. the method improves the high-temperature plasticity of the low-carbon austenitic stainless steel by controlling the De-f value of the low-carbon austenitic stainless steel, controls the surface quality and the macrostructure of a continuous casting blank by measures such as cooling water, covering slag and the like in the smelting and continuous casting processes, ensures that the defects such as surface cracks, scabs and the like do not exist, reduces the cracking risk of the low-carbon austenitic stainless steel rod, and improves the yield and the qualification rate;
2. according to the invention, by observing the current of the motor in the rolling process, when the load reaches 90% of the rated load, the temperature of the heating furnace is adjusted and raised in time or the time in the furnace is prolonged properly, and the phenomenon that the load exceeds 90% of the rated load is ensured to be avoided, so that the overload operation of the steel rolling equipment can be avoided, and the service life of the steel rolling equipment is prolonged.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below. It should be apparent that the drawings in the following description are merely exemplary, and that other embodiments can be derived from the drawings provided by those of ordinary skill in the art without inventive effort.
The structures, ratios, sizes, and the like shown in the present specification are only used for matching with the contents disclosed in the specification, so that those skilled in the art can understand and read the present invention, and do not limit the conditions for implementing the present invention, so that the present invention has no technical significance, and any structural modifications, changes in the ratio relationship, or adjustments of the sizes, should fall within the scope covered by the technical contents disclosed in the present invention without affecting the effects and the achievable purposes of the present invention.
FIG. 1 is a picture of a crack of a 316L low carbon austenitic stainless steel bar produced by a conventional process provided by the present invention;
FIG. 2 is a metallographic picture of a 316L low carbon austenitic stainless steel bar produced by a conventional process provided by the present invention;
FIG. 3 is an electronic image picture of a 316L low-carbon austenitic stainless steel bar electron probe produced by a conventional process provided by the invention;
FIG. 4 is a picture of a crack in a 316L low carbon austenitic stainless steel bar produced by a conventional process provided by the present invention;
FIG. 5 is a metallographic picture of a 316L low carbon austenitic stainless steel bar produced by a conventional process according to the present invention;
FIG. 6 is an electronic image picture of a 316L low carbon austenitic stainless steel bar electron probe produced by a conventional process provided by the present invention;
FIG. 7 is a surface quality picture of 316L low carbon austenitic stainless steel bar produced by the process of the present invention;
FIG. 8 is a metallographic picture of 316L low carbon austenitic stainless steel bars produced by the process of the present invention;
FIG. 9 is an electronic image picture of a 316L low-carbon austenitic stainless steel bar electron probe produced by the process of the present invention.
Detailed Description
The present invention is described in terms of particular embodiments, other advantages and features of the invention will become apparent to those skilled in the art from the following disclosure, and it is to be understood that the described embodiments are merely exemplary of the invention and that it is not intended to limit the invention to the particular embodiments disclosed. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1:
the low-carbon austenitic stainless steel bar is produced by applying a conventional process, and the steps are as follows:
the method comprises the following steps: chemical components: low carbon austeniteThe steel 316L is made according to the national standard: c is less than or equal to 0.03 percent, Si is less than or equal to 1.0 percent, Mn is less than or equal to 2.0 percent, P is less than or equal to 0.045 percent, S is less than or equal to 0.030 percent, the content of Cr is 16.00 to 18.00 percent, the content of Ni is 10.00 to 14.00 percent, the content of Mo is 2.00 to 3.00 percent, and the smelting finished products comprise the following components in a first group: 0.018% of C, 0.37% of Si, 0.99% of Mn, 0.031% of P, 0.0067% of S, 16.21% of Cr, 10.07% of Ni, 2.03% of Mo, 0.13% of Cu, 0.001% of Ti, 0.068% of N, and 1.73% of De-f; second group: 0.014% of C, 0.39% of Si, 0.91% of Mn, 0.032% of P, 0.0009% of S, 16.50% of Cr, 10.05% of Ni, 2.05% of Mo, 0.07% of Cu, 0.002% of Ti, 0.031% of N, and 6.13% of De-f, wherein the calculation formula used in the calculation of De-f is as follows
Step two: smelting and continuous casting: according to the normal process organization production, the surface quality and the macrostructure of the continuous casting billet are controlled by measures such as cooling water, covering slag and the like. The surfaces of the continuous casting billets with the two groups of chemical components have no obvious defects such as cracks, scabs and the like; macrostructure, first group: the center porosity is 0.5 grade, the center segregation is 0.5 grade, and the shrinkage cavity is 0.5 grade; second group: the center porosity is 0.5 grade, the center segregation is 1.0 grade, and the shrinkage cavity is 0.5 grade;
step three: heating the furnace: two groups of continuous casting billets with chemical components enter a heating furnace in two batches, wherein the first batch is half of the first group, namely 1A + half of the second group, namely 2A, and the second batch is the remaining half of the first group, namely 1B + the remaining half of the second group, namely 2B. Two batches of continuous casting billets with chemical components are fed into a furnace: the preheating section is less than or equal to 980 ℃, the air-coal ratio of the heating section and the soaking section is set to be 0.85, and the pressure in the furnace is 25 Pa; the temperature of the heating section is 1200 ℃ in the first batch and 1150 ℃ in the second batch; the temperature of the soaking section is 1220 ℃ in the first batch and 1180 ℃ in the second batch. The two batches are cold charged into the furnace for 200 min. The temperature fluctuation is controlled within +/-10 ℃;
step four: rolling mill: rolling according to conventional operation, observing the current of a motor, wherein the first batch does not have the phenomenon of exceeding 90% of rated load; the second batch has the condition of 98 percent of rated load, and steel is directly tapped without adjustment.
Example 2:
the invention provides a method for producing a low-carbon austenitic stainless steel bar by reducing the load of a rolling mill, which comprises the following steps:
step one, the national standard requirement of low carbon austenitic stainless steel 316L: less than or equal to 0.03 percent of C, less than or equal to 1.0 percent of Si, less than or equal to 2.0 percent of Mn, less than or equal to 0.045 percent of P, less than or equal to 0.030 percent of S, 16.00 to 18.00 percent of Cr16, 10.00 to 14.00 percent of Nis and 2.00 to 3.00 percent of Mos. The chemical components of the low-carbon austenitic stainless steel are determined according to the national standard: 0.025% of C, 0.50% of Si, 0.90% of Mn, 0.04% of P, 0.002% of S, 16.14% of Cr, 10.02% of Ni, 2.04% of Mo, 0.31% of Cu, 0.001% of Ti, and 0.039% of N, and calculating to obtain De-f of 4.06%, wherein a calculation formula used in the calculation process of calculating De-f is as follows
And the content of each element component can be properly adjusted according to the production stability.
Step two, adding a certain amount of Cu element to the low-carbon austenitic stainless steel rod in order to ensure subsequent perforation or machining, and if Cu is more than or equal to 0.35%, ensuring that S is less than or equal to 0.0015% and avoiding the formation of a low-melting-point compound CuS;
determining the in-furnace time before rolling according to whether the continuous casting billet is a cold billet or a hot billet and the section size of the continuous casting billet, wherein the in-furnace time of the hot billet of the continuous casting billet with the section of 180 multiplied by 180 mm-200 multiplied by 200mm is generally 120-150 min, and the in-furnace time of the cold billet of the continuous casting billet with the section of 180 multiplied by 180 mm-200 multiplied by 200mm is generally 180-210 min;
step four, smelting and continuous casting: the surface quality and the macroscopic structure of the continuous casting billet are controlled by measures such as cooling water, covering slag and the like, the defects such as surface cracks, scabs and the like are ensured to be avoided, and the macroscopic defect level such as center porosity, center segregation, shrinkage cavity and the like is less than or equal to 1.5 level;
step five, heating the furnace: controlling the atmosphere and air quantity in the heating furnace, ensuring the fuel to be fully combusted, and not causing the furnace to have obvious oxidizing atmosphere, wherein the air-coal ratio of the heating section and the soaking section is 0.7-0.9, the furnace is in a micro-positive pressure state, the temperature of the preheating section is kept in a conventional process, the temperature of the heating section and the soaking section is increased by 20-40 ℃, the furnace time of a hot blank is 120-150 min, the furnace time of a cold blank is 180-210 min, wherein the temperature of the preheating section is less than or equal to 980 ℃, the temperature of the heating section is 1200 ℃, the temperature of the soaking section is 1220 ℃, cold charging is carried out in the furnace, the furnace time is 200min, the air-coal ratio of the heating section and the soaking section is 0.85, the pressure in the furnace is 25Pa, and the temperature fluctuation is controlled within +/-10 ℃;
step six, rolling: rolling by using a rolling mill according to conventional operation, paying attention to observing the current of a motor, raising the temperature of a heating furnace or properly prolonging the furnace time when the load reaches 90% of the rated load, determining that the phenomenon of exceeding 90% of the rated load does not exist, and controlling the De-f value to be within the range of 3% -5%.
Example 3:
the products obtained in the above two examples were observed and compared, and compared with the cracking phenomenon (more, occasional, no cracking), the maximum crack length (mm), and the content (%) of the second grade, respectively, and the comparison results are shown in the following table:
according to the description in the table, it can be known that the stainless steel rods of two batches prepared according to the conventional process have cracking phenomena under different conditions, wherein the majority of the stainless steel rods in the first batch prepared according to the conventional process have more cracking phenomena, the maximum crack length is 1.2mm, and 80% of the stainless steel rods in the whole first batch are judged to be the second-class product according to statistics; the cracking phenomenon of most stainless steel rods in the second batch prepared according to the conventional process is obviously reduced compared with that of the first batch, but the cracking phenomenon still occasionally occurs in the second batch, wherein the maximum crack length is 0.3mm, although the process is improved compared with that of the first batch, the cracking phenomenon existing in the second batch still affects the qualification rate of the product, and 20 percent of the products are judged as second-class products. The surface and the metallographic morphology of the product produced by the conventional process are shown in pictures 1-6. Through careful observation, the cracking phenomenon is not found in a plurality of stainless steel rods prepared by the method for producing the low-carbon austenitic stainless steel rod by reducing the load of the rolling mill, and the steel rod which is judged as the second-class product is not found in all products, and specific product pictures and metallographic morphology can be seen in pictures 7-9. In conclusion, the invention can improve the high-temperature plasticity of the low-carbon austenitic stainless steel by controlling the De-f value of the low-carbon austenitic stainless steel, organize the production under the condition of reducing the load of a rolling mill, reduce the cracking risk of the low-carbon austenitic stainless steel rod, and improve the yield and the qualification rate, and the invention can timely adjust and raise the temperature of a heating furnace or properly prolong the time in the furnace by observing the current of a motor when the load reaches 90 percent of the rated load in the rolling process, thereby ensuring that the phenomenon of exceeding 90 percent of the rated load does not occur, avoiding the overload operation of steel rolling equipment and prolonging the service life of the steel rolling equipment.
Although the invention has been described in detail above with reference to a general description and specific examples, it will be apparent to one skilled in the art that modifications or improvements may be made thereto based on the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.
Claims (5)
1. A method for producing low-carbon austenitic stainless steel bars by reducing the load of a rolling mill is characterized by comprising the following steps: the method comprises the following steps:
step one, determining chemical components of the low-carbon austenitic stainless steel according to national standard requirements: 0.025% of C, 0.50% of Si, 0.90% of Mn, 0.04% of P, 0.002% of S, 16.14% of Cr, 10.02% of Ni, 2.04% of Mo, 0.31% of Cu, 0.001% of Ti and 0.039% of N, and calculating according to the component content to obtain De-f which is 4.06%;
step two, adding a certain amount of Cu element to the low-carbon austenitic stainless steel rod in order to ensure subsequent perforation or machining, and if Cu is more than or equal to 0.35%, ensuring that S is less than or equal to 0.0015% and avoiding the formation of a low-melting-point compound CuS;
determining the in-furnace time before rolling according to whether the continuous casting billet is a cold billet or a hot billet and the section size of the continuous casting billet, wherein the in-furnace time of the hot billet of the continuous casting billet with the section of 180 multiplied by 180 mm-200 multiplied by 200mm is generally 120-150 min, and the in-furnace time of the cold billet of the continuous casting billet with the section of 180 multiplied by 180 mm-200 multiplied by 200mm is generally 180-210 min;
step four, smelting and continuous casting: the surface quality and the macroscopic structure of the continuous casting billet are controlled by measures such as cooling water, covering slag and the like, the defects such as surface cracks, scabs and the like are ensured to be avoided, and the macroscopic defect level such as center porosity, center segregation, shrinkage cavity and the like is less than or equal to 1.5 level;
step five, heating the furnace: controlling the atmosphere and the air quantity in the heating furnace, ensuring that the fuel is fully combusted, and preventing the furnace from generating obvious oxidizing atmosphere, wherein the air-coal ratio of a heating section and a soaking section is set to be 0.7-0.9, the furnace is in a micro-positive pressure state, the temperature of a preheating section is kept in a conventional process, the temperature of the heating section and the soaking section is increased by 20-40 ℃, the furnace time of a hot blank is 120-150 min, and the furnace time of a cold blank is 180-210 min;
step six, rolling: rolling by using a rolling mill according to conventional operation, observing the current of a motor, adjusting the temperature of a heating furnace in time or properly prolonging the furnace time when the load reaches 90% of the rated load, determining that the phenomenon of exceeding 90% of the rated load does not exist, and controlling the De-f value within 3% -5%.
2. The method for producing the low-carbon austenitic stainless steel bar according to the claim 1, characterized in that: in step one, the calculation of De-f is shown as follows
3. The method for producing the low-carbon austenitic stainless steel bar according to the claim 1, characterized in that: in the first step, the content of each element component can be properly adjusted according to the production stability condition, but the corresponding standard is ensured to be met and the De-f value is ensured to be in the range of 3-5%.
4. The method for producing the low-carbon austenitic stainless steel bar according to the claim 1, characterized in that: in step one, the national standard requirement of the low carbon austenitic stainless steel 316L is as follows: less than or equal to 0.03 percent of C, less than or equal to 1.0 percent of Si, less than or equal to 2.0 percent of Mn, less than or equal to 0.045 percent of P, less than or equal to 0.030 percent of S, 16.00 to 18.00 percent of Cr16, 10.00 to 14.00 percent of Nis and 2.00 to 3.00 percent of Mos.
5. The method for producing the low-carbon austenitic stainless steel bar according to the claim 1, characterized in that: in the fifth step, the preheating section is less than or equal to 980 ℃, the heating section is 1200 ℃, the soaking section is 1220 ℃, the cold charge is carried out in the furnace, the furnace time is 200min, the air-coal ratio set value of the heating section and the soaking section is 0.85, the pressure in the furnace is 25Pa, and the temperature fluctuation control is within +/-10 ℃.
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