CN113293272B - Method for improving high-nitrogen duplex stainless steel strong plasticity - Google Patents
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- C—CHEMISTRY; METALLURGY
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- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
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- C21D1/26—Methods of annealing
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- 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
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
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- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
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- C21D2211/001—Austenite
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- C21D2211/00—Microstructure comprising significant phases
- C21D2211/005—Ferrite
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Abstract
The invention relates to a method for improving the strong plasticity of high-nitrogen duplex stainless steel, which is characterized by sequentially comprising the following steps of: 1) Carrying out hot rolling on the cast ingot of the duplex stainless steel, and carrying out water cooling treatment after the hot rolling; 2) Carrying out homogenization solution annealing treatment on the hot-rolled duplex stainless steel, wherein the annealing temperature is 1050-1200 ℃, and the heat preservation time is 1-4 h; 3) Performing cold rolling treatment on the duplex stainless steel treated in the step 2), wherein the total reduction rate is 60-80%; 4) And (3) carrying out high-temperature rapid annealing treatment on the cold-rolled duplex stainless steel at the annealing temperature of 1100-1200 ℃ for 10-90 s, and then carrying out water cooling. The problem of strong plasticity matching of the high-nitrogen duplex stainless steel is effectively solved through TRIP effect strengthening, fine grain strengthening and back stress strengthening, and the yield strength, the tensile strength and the elongation of the high-nitrogen duplex stainless steel are improved.
Description
Technical Field
The invention belongs to the technical field of steel alloy materials, and particularly relates to a method for improving the strong plasticity of high-nitrogen duplex stainless steel.
Background
The duplex stainless steel has multiple advantages of excellent mechanical property, corrosion resistance, low alloy cost and the like, plays an important role in national economic construction, has wide application prospect in the fields of paper making industry, petrochemical industry, ocean platforms, ship transportation, nuclear power, food industry, building industry and the like, and becomes one of the main trends of future development of the stainless steel industry. The traditional duplex stainless steel contains more Ni elements, and China is a country with relatively short Ni resources. The large consumption of Ni resource causes the severe fluctuation of price, which causes the high cost of stainless steel alloy and influences the popularization and application of duplex stainless steel. Therefore, the resource-saving duplex stainless steel with high strength and high plasticity is a hotspot of current research, and is expected to be used as high-strength corrosion-resistant structural steel in corrosive environment, so that the service life of the material is prolonged, and the whole-cycle cost is reduced.
In order to ensure the service safety of the material, higher requirements are put forward on the comprehensive mechanical properties of the duplex stainless steel. Therefore, it is critical to improve the tensile plasticity of the duplex stainless steel while improving the strength. The strengthening mechanism of the traditional duplex stainless steel is mainly solid solution strengthening of alloy elements, and the improvement degree of the traditional duplex stainless steel on the strength and the plasticity is limited. For the industrial preparation of the duplex stainless steel, the cold rolling process is simple and easy. The duplex stainless steel after cold rolling has high strength but extremely poor plasticity. After the conventional solution treatment (keeping the temperature at 1000-1100 ℃ for 5-30 min), the elongation is improved, but the strength is greatly reduced. Therefore, a new alloy component design method and a heat treatment process are developed, and the further improvement of the strong plasticity matching of the duplex stainless steel has important theoretical significance and practical application value.
For example, the invention patent of china, "a near-net-shape manufacturing method of duplex stainless steel thin strip", whose patent number is ZL201510993001.5 (publication number is CN 105543714B), discloses a duplex stainless steel, which comprises the following components by mass percent: c:0.0001 to 0.03 percent; cr:18 to 22 percent; mn:5 to 7 percent; n:0.3 to 0.45 percent; ni:0.0001 to 0.1 percent; the balance being iron and other unavoidable impurities. The cost is reduced by replacing Ni with Mn and N, the nitrogen content in the duplex stainless steel is increased to more than 0.3 percent, the aim of saving Ni resources can be achieved, the content and the stability of an austenite phase in the duplex stainless steel can be ensured, excellent comprehensive mechanical property is obtained, and meanwhile, the excellent corrosion property can be ensured because the nitrogen can improve the pitting corrosion resistance and crevice corrosion resistance of the duplex stainless steel. The product of strength and elongation of the duplex stainless steel obtained by the near net shaping preparation method reaches 65GPa%, the elongation rate is 45-65%, and the tensile strength is 800-1100 MPa. Although the product of strength and elongation of the steel is high, the yield strength is low and is only 500-600 MPa, and when the steel is used as a structural part, once the external load exceeds the yield limit, the structure can be permanently deformed, and the service safety is influenced. Therefore, in order to increase the safety factor of the material, the yield strength and tensile strength of the material need to be further improved while the material is ensured to have a higher product of strength and elongation.
For another example, the chinese invention patent "heat treatment process of a high-strength plastic ferrite-austenite duplex stainless steel", whose patent number is ZL201910022542.1 (publication number is CN 109487060B), discloses a heat treatment process of a high-strength plastic ferrite-austenite duplex stainless steel, which adopts "primary solid solution treatment + pre-deformation + secondary solid solution treatment" to obtain a duplex structure of an equiaxial austenite grain phase + a ferrite matrix phase, and increases the material strength product to 32916MPa% (32.916 GPa%). However, the product of strength and elongation is still low, and may not meet the requirements of some severe service environments on materials. As another example, the chinese patent application, CN201910412901.4 (application publication No. CN 111944973A), discloses a method for preparing a duplex stainless steel with a heterogeneous layered structure, which obtains the duplex stainless steel with the heterogeneous layered structure through "deep cold rolling + incomplete recrystallization annealing", wherein the structure of the duplex stainless steel consists of a recrystallized structure in ferrite, an ultrafine crystal structure and a twin crystal structure in austenite. On the basis of keeping the strength of the superfine duplex stainless steel, the structure improves the plasticity of the superfine duplex stainless steel through back stress strengthening, the strength can reach 1245MPa, and the elongation reaches 12%. However, the adoption of the incomplete recrystallization annealing treatment can leave large residual stress in the material, reduce the corrosion resistance of the material and influence the service safety of the material in a corrosive environment. In addition, a non-uniform layered structure is obtained by cold rolling and low-temperature annealing, and the performance is improved by grain refinement and back stress strengthening, but the method has the advantages that the product of strength and elongation is low, and in addition, as the duplex stainless steel contains more elements such as Cr, mo, N and the like, brittle phases such as nitrides and sigma are easily precipitated during low-temperature (900-1000 ℃) annealing treatment, so the ductility, toughness and corrosion resistance of the material are deteriorated.
Therefore, further improvement of the existing method for improving the strength and plasticity of duplex stainless steel is required.
Disclosure of Invention
The technical problem to be solved by the invention is to provide a method for improving the strong plasticity of the high-nitrogen duplex stainless steel, which aims at the current situation of the prior art and obtains high tensile strength, yield strength and high strength-plasticity product.
The technical scheme adopted by the invention for solving the technical problems is as follows: the method for improving the strong plasticity of the high-nitrogen duplex stainless steel is characterized by sequentially comprising the following steps of:
1) Carrying out hot rolling on the cast ingot of the duplex stainless steel, and carrying out water cooling treatment after the hot rolling;
2) Carrying out homogenization solution annealing treatment on the hot-rolled duplex stainless steel, wherein the annealing temperature is 1050-1200 ℃, and the heat preservation time is 1-4 h;
3) Performing cold rolling treatment on the duplex stainless steel treated in the step 2), wherein the total reduction rate is 60-80%;
4) And (3) carrying out high-temperature rapid annealing treatment on the cold-rolled duplex stainless steel at the annealing temperature of 1100-1200 ℃ for 10-90 s, and then carrying out water cooling.
In the step 2), the hot-rolled duplex stainless steel is subjected to uniform annealing treatment to eliminate thermal deformation stress and work hardening, so that a ferrite and austenite duplex structure with large grain size is obtained. And subsequent water cooling to suppress the precipitation of brittle phases. In the step 3), the initial structure is crushed through large deformation, and a layered fine-grain composite structure of ferrite, austenite and strain induced martensite is formed. In the step 4), high-temperature rapid annealing treatment is adopted, and the duplex stainless steel with the heterostructure of 'recrystallized ferrite + ultrafine grain/nanocrystalline austenite' is finally prepared.
Preferably, the high-nitrogen duplex stainless steel comprises the following components, by mass, 0.01-0.04%; 17 percent or more of Cr and 23 percent or less of Cr; mo is more than or equal to 0.01 and less than or equal to 0.15 percent; ni is more than or equal to 0.01 and less than or equal to 1.5 percent; mn is more than or equal to 4 and less than or equal to 8 percent; n is more than or equal to 0.2 and less than or equal to 0.45 percent; the balance being iron and other unavoidable impurities.
The component design of the alloy fully considers 'Mn + N replaces Ni', on one hand, the aim of saving Ni resources and reducing cost can be achieved; on the other hand, the content of Mn and N elements can be regulated and controlled, the influence on the stability of austenite is realized, metastable austenite is obtained, the TRIP effect of gamma → epsilon-martensite → alpha' -martensite is generated in the deformation process of the high-nitrogen double-phase stainless steel, namely the fault energy of an austenite layer is reasonably regulated and controlled, the martensite transformation can be generated in the deformation process, and the strong plasticity is improved by utilizing the TRIP effect. In addition, the higher nitrogen content can improve the pitting corrosion resistance and crevice corrosion resistance of the duplex stainless steel and can ensure excellent corrosion performance, thereby improving the service safety of the material in a corrosive environment.
Preferably, the initial temperature of the hot rolling in step 1) is 1150-1250 ℃ and the final rolling temperature is 900-1000 ℃.
In order to suppress the precipitation of brittle phases, water cooling is used after the annealing treatment in step 2).
Preferably, after the step 4), the tensile strength of the duplex stainless steel is 1000-1200 MPa, the yield strength is 700-950 MPa, and the elongation after fracture is 40-65%. In this way, high tensile strength, high yield strength and good elongation after fracture are obtained.
Preferably, the ingot in step 1) is an ingot obtained by smelting in a vacuum induction smelting furnace under the protection of a nitrogen atmosphere. In addition, other melting furnaces may be used in other non-oxidizing atmospheres.
Compared with the prior art, the invention has the advantages that: compared with the traditional duplex stainless steel, the high-nitrogen duplex stainless steel with metastable austenite can refine the original structure on one hand and can generate strain-induced martensite transformation on the other hand in the cold rolling large deformation process to form a layered fine-grain composite structure of ferrite, austenite and strain-induced martensite, thereby effectively improving the tensile strength and the yield strength; the high-nitrogen dual-phase stainless steel with a heterostructure of 'recrystallized ferrite + ultrafine grain/nanocrystalline austenite' is prepared by 'large deformation + high-temperature rapid annealing'. The problem of strong plasticity matching is effectively improved through TRIP effect strengthening, fine grain strengthening and back stress strengthening, and the method is convenient for further industrial application. In addition, compared with the prior art, the annealing temperature is higher, so that the homogenization of alloy components and the dissolution of brittle phases such as carbonitride can be ensured, and the risks of element segregation and brittle phase precipitation are reduced. Meanwhile, high-temperature rapid annealing is adopted, so that fine grains can be obtained to improve the strength, and compared with incomplete recrystallization annealing, the method can ensure higher recrystallization and reduce the adverse effect of residual stress on the corrosion resistance, thereby improving the comprehensive service performance of the high-nitrogen duplex stainless steel.
Drawings
FIG. 1 is a process flow of the present invention for preparing high-nitrogen duplex stainless steel by high-temperature rapid annealing;
FIG. 2 is a microstructure of a high nitrogen duplex stainless steel according to example 1 of the present invention after a large deformation cold rolling;
FIG. 3 is a drawing curve of a high nitrogen duplex stainless steel according to example 1 of the present invention;
FIG. 4 shows the microstructure of a high-nitrogen duplex stainless steel according to example 1 of the present invention after a high-temperature rapid annealing treatment.
Detailed Description
The invention is described in further detail below with reference to the accompanying examples.
Example 1:
as shown in fig. 1 to 4, the invention is the 1 st preferred embodiment. The high-nitrogen duplex stainless steel of the embodiment comprises the following components in percentage by mass: c =0.02%, cr =19.20%, mo =0.01%, ni =0.05%, mn =6.13%, N =0.37%; the balance being iron and other unavoidable impurities.
The components with the contents are placed in a vacuum induction melting furnace, and cast and melted under the protection of nitrogen atmosphere to obtain the cast ingot of the high-nitrogen stainless steel.
As shown in FIG. 1, the method for improving the high-nitrogen duplex stainless steel strength and plasticity sequentially comprises the following steps:
1) Hot rolling the ingot of the duplex stainless steel, wherein the initial temperature of the hot rolling is 1200 ℃, the final rolling temperature is 980 ℃, and the hot rolling is followed by water cooling treatment to inhibit the precipitation of brittle phases such as carbonitride;
2) Carrying out homogenization solution annealing treatment (intermediate annealing) on the hot-rolled duplex stainless steel, wherein the annealing temperature is 1100 ℃, the heat preservation time is 2 hours, and then carrying out water cooling to inhibit the precipitation of brittle phases; and (3) carrying out uniform annealing treatment on the hot-rolled duplex stainless steel, eliminating thermal deformation stress and carrying out work hardening to obtain a large-grain-size ferrite-austenite duplex structure.
3) Cold rolling the duplex stainless steel treated in the step 2), wherein the total reduction rate is 75%, and the initial structure is crushed through large deformation to form a layered fine-grained ferrite + austenite + strain-induced martensite composite structure; referring specifically to FIG. 2, where A is austenite, F is ferrite, and ε -M and α' -M are strain-induced martensite.
4) And (3) carrying out high-temperature rapid annealing treatment (final heat treatment) on the cold-rolled duplex stainless steel, wherein the annealing temperature is 1150 ℃, after the furnace temperature reaches the annealing temperature value, putting the cold-rolled sheet into a furnace, annealing for 20s, and then cooling with water to inhibit the precipitation of brittle phases, thereby preparing the duplex stainless steel with the 'recrystallized ferrite + ultrafine crystal/nanocrystalline austenite' heterostructure. In fig. 4, the dark color is austenite and the light color is ferrite.
By adopting conventional solution treatment (1050 ℃, heat preservation for 300s and water cooling), the tensile strength of the high-nitrogen duplex stainless steel is 1000MPa, the yield strength is 550MPa, the elongation after fracture is 57 percent, and the product of strength and elongation is 57GPa percent. The tensile strength of the high-nitrogen duplex stainless steel improved by the high-temperature rapid annealing method is 1100MPa, the yield strength is 800MPa, the elongation after fracture is 52 percent, and the product of strength and elongation is 57.2GPa percent, which is shown in figure 3.
The method improves the tensile strength, the yield strength and the product of strength and elongation of the high-nitrogen duplex stainless steel.
Example 2:
this embodiment differs from embodiment 1 above only in that: the method for improving the high-nitrogen duplex stainless steel has different technological parameters, and specifically, the annealing time in the step 4) is 30s.
In this example, after the high-nitrogen duplex stainless steel is subjected to high-temperature rapid annealing, the tensile strength is 1000MPa, the yield strength is 700MPa, and the elongation after fracture is 58%. Due to the longer annealing time, the crystal grains grow up, the elongation is increased, and the product of strength and elongation is 58GPa%. Compared with the conventional solution treatment (1050 ℃, heat preservation for 300s and water cooling), the tensile strength is basically the same, but the yield strength is obviously improved, and the product of strength and elongation is slightly improved.
Example 3:
this embodiment differs from the above embodiment 1 only in that:
the high-nitrogen duplex stainless steel has different contents of components, and specifically comprises the following components in percentage by mass: c =0.04%, cr =22.8%, mo =0.01%, ni =1.5%, mn =7.8%, N =0.24%, and the balance being iron and other unavoidable impurities.
The method for improving the high-nitrogen duplex stainless steel strong plasticity is different in technological parameters, and specifically, the initial temperature of hot rolling in the step 1) is 1250 ℃, and the final rolling temperature is 1000 ℃; the annealing temperature in the step 2) is 1050 ℃; the total reduction in step 3) was 65%.
By adopting conventional solution treatment (1050 ℃, heat preservation for 300s and water cooling), the tensile strength of the high-nitrogen duplex stainless steel is 950MPa, the yield strength is 520MPa, the elongation after fracture is 45 percent, and the product of strength and elongation is 42.75GPa%. The tensile strength of the high-nitrogen duplex stainless steel improved by the method is 1060MPa, the yield strength is 750MPa, the elongation after fracture is 42 percent, and the product of strength and elongation of the high-nitrogen duplex stainless steel is 44.52GPa. The method improves the tensile strength and the yield strength of the high-nitrogen duplex stainless steel.
Example 4:
this embodiment differs from the above embodiment 1 only in that:
the high-nitrogen duplex stainless steel has different contents of components, and specifically comprises the following components in percentage by mass: c =0.03%, cr =17.5%, mo =0.15%, ni =0.02%, mn =4.3%, N =0.30%, and the balance is iron and other unavoidable impurities.
The method for improving the strong plasticity of the high-nitrogen duplex stainless steel has different technological parameters, and specifically, the finishing temperature in the step 1) is 980 ℃; the annealing temperature in the step 2) is 1200 ℃, and the heat preservation time is 1h; the total reduction rate in the step 3) is 80 percent; the annealing time in step 4) was 60s.
By adopting conventional solution treatment (1050 ℃, heat preservation for 300s and water cooling), the tensile strength of the high-nitrogen duplex stainless steel is 950MPa, the yield strength is 550MPa, the elongation after fracture is 50 percent, and the product of strength and elongation is 47.5GPa%. The tensile strength of the high-nitrogen duplex stainless steel improved by the method is 1020MPa, the yield strength is 730MPa, the elongation after fracture is 51 percent, and the product of strength and elongation of the high-nitrogen duplex stainless steel is 52.02GPa.
The method improves the tensile strength, the yield strength and the product of strength and elongation of the high-nitrogen duplex stainless steel.
Example 5:
this embodiment differs from the above embodiment 1 only in that:
the high-nitrogen duplex stainless steel has different contents of components, and specifically comprises the following components in percentage by mass: c =0.02%, cr =22.1%, mo =0.05%, ni =0.01%, mn =7.5%, N =0.43%, and the balance being iron and other unavoidable impurities.
The method for improving the strong plasticity of the high-nitrogen duplex stainless steel has different technological parameters, and specifically, the finish rolling temperature in the step 1) is 930 ℃; the annealing temperature in the step 2) is 1200 ℃, and the heat preservation time is 1h; the total reduction rate in the step 3) is 70 percent; the annealing temperature in the step 4) is 1200 ℃, and the annealing time is 10s.
By adopting conventional solution treatment (1050 ℃, heat preservation for 300s and water cooling), the tensile strength of the high-nitrogen duplex stainless steel is 1080MPa, the yield strength is 700MPa, the elongation after fracture is 42 percent, and the product of strength and elongation is 45.36GPa%. The tensile strength of the high-nitrogen duplex stainless steel improved by the method is 1190MPa, the yield strength is 930MPa, the elongation after fracture is 40 percent, and the product of strength and elongation of the high-nitrogen duplex stainless steel is 47.6GPa.
The method improves the tensile strength, the yield strength and the product of strength and elongation of the high-nitrogen duplex stainless steel.
Example 6:
this embodiment differs from the above embodiment 1 only in that:
the high-nitrogen duplex stainless steel has different contents of components, and specifically comprises the following components in percentage by mass: c =0.01%, cr =17%, mo =0.05%, ni =0.01%, mn =4%, N =0.2%, and the balance being iron and other unavoidable impurities.
The method for improving the strong plasticity of the high-nitrogen duplex stainless steel has different process parameters, and specifically, the finishing temperature in the step 1) is 900 ℃; the annealing temperature in the step 2) is 1050 ℃, and the heat preservation time is 4h; the annealing temperature in the step 4) is 1200 ℃, and the annealing time is 90s.
By adopting conventional solution treatment (1050 ℃, heat preservation for 300s and water cooling), the tensile strength of the high-nitrogen duplex stainless steel is 900MPa, the yield strength is 520MPa, the elongation after fracture is 60 percent, and the product of strength and elongation is 54GPa%. The tensile strength of the high-nitrogen duplex stainless steel improved by the method is 1000MPa, the yield strength is 700MPa, the elongation after fracture is 65 percent, and the product of strength and elongation of the high-nitrogen duplex stainless steel is 65GPa percent.
The method improves the tensile strength, the yield strength and the product of strength and elongation of the high-nitrogen duplex stainless steel.
Example 7:
this embodiment differs from the above embodiment 1 only in that:
the high-nitrogen duplex stainless steel has different contents of components, and specifically comprises the following components in percentage by mass: c =0.01%, cr =23%, mo =0.01%, ni =0.01%, mn =8%, N =0.45%, and the balance being iron and other unavoidable impurities.
The method for improving the strong plasticity of the high-nitrogen duplex stainless steel has different process parameters, and specifically, the initial temperature in the step 1) is 1150 ℃; the annealing temperature in the step 4) is 1200 ℃, and the annealing time is 10s.
By adopting conventional solution treatment (1050 ℃, heat preservation for 300s and water cooling), the tensile strength of the high-nitrogen duplex stainless steel is 1050MPa, the yield strength is 730MPa, the elongation after fracture is 55 percent, and the product of strength and elongation is 57.75GPa%. The tensile strength of the high-nitrogen duplex stainless steel improved by the method is 1200MPa, the yield strength is 950MPa, the elongation after fracture is 51 percent, and the product of strength and elongation of the high-nitrogen duplex stainless steel is 61.2GPa percent.
The method improves the tensile strength, the yield strength and the product of strength and elongation of the high-nitrogen duplex stainless steel.
The performance of the high nitrogen duplex stainless steel improved by the new method is compared with the conventional solution treatment in the following table 1 according to the embodiments 1 to 7 of the present invention.
TABLE 1
Compared with the conventional solution treatment (1050 ℃ multiplied by 300 s), the tensile strength, the yield strength and the product of strength and elongation of the steel plate can be improved to different degrees by adopting the improvement method (novel process) of the invention in each embodiment.
Claims (5)
1. The method for improving the strong plasticity of the high-nitrogen duplex stainless steel is characterized in that the duplex stainless steel comprises the following components by mass percent, wherein C is more than or equal to 0.01 and less than or equal to 0.04%;17 percent or more of Cr and 23 percent or less of Cr; mo is more than or equal to 0.01 and less than or equal to 0.15 percent; ni is more than or equal to 0.01 and less than or equal to 1.5 percent; mn is more than or equal to 4 percent and less than or equal to 8 percent; n is more than or equal to 0.2 and less than or equal to 0.45 percent; the balance of iron and other inevitable impurities, the method comprising the following steps in sequence:
1) Carrying out hot rolling on the cast ingot of the duplex stainless steel, and carrying out water cooling treatment after the hot rolling;
2) Carrying out homogenization solution annealing treatment on the hot-rolled duplex stainless steel, wherein the annealing temperature is 1050-1200 ℃, and the heat preservation time is 1-4 h;
3) Performing cold rolling treatment on the duplex stainless steel treated in the step 2), wherein the total reduction rate is 60-80%;
4) And (3) carrying out high-temperature rapid annealing treatment on the cold-rolled duplex stainless steel at the annealing temperature of 1100-1200 ℃ for 10-90 s, and then carrying out water cooling.
2. The method of claim 1, wherein: the initial temperature of hot rolling in the step 1) is 1150-1250 ℃, and the final rolling temperature is 900-1000 ℃.
3. The method of claim 1, wherein: and (3) water cooling is adopted after the annealing treatment in the step 2).
4. The method of claim 1, wherein: after the step 4), the tensile strength of the duplex stainless steel is 1000-1200 MPa, the yield strength is 700-950 MPa, and the elongation after fracture is 40-65%.
5. The method of claim 1, wherein: and 4) smelting the cast ingot in the step 1) by using a vacuum induction smelting furnace under the protection of nitrogen atmosphere to obtain the cast ingot.
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| CN103526130B (en) * | 2013-10-23 | 2017-01-11 | 北京科技大学 | Processing method for direct cold rolling of two-phase stainless steel as-cast state billet steel after solid solution treatment |
| CN105886956B (en) * | 2016-07-01 | 2017-10-31 | 东北大学 | A kind of economizing type two-phase stainless steel sheet and preparation method thereof |
| CN106435131B (en) * | 2016-08-31 | 2019-07-23 | 东北大学 | The method that deep cooling rolling-short annealing prepares nanocrystalline austenite stainless steel plate |
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2021
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