Method for improving corrosion resistance of high-nitrogen austenitic stainless steel

Abstract

The invention discloses a method for improving corrosion resistance of high-nitrogen austenitic stainless steel, and belongs to a stainless steel hot working technology. The method comprises the following steps: (1) preparing an austenitic stainless steel raw material, refining to obtain a casting blank, then carrying out pre-forging treatment, and carrying out water cooling to obtain a pre-forged plate; (2) the pre-forged plate is subjected to solid solution heat treatment and water cooling, and a solid solution heat treatment material is obtained; (3) carrying out tissue homogenization treatment on the solid solution treatment material at 1200 DEG C, and keeping the temperature for 5 minutes; (4) cooling to the deformation temperature of 1050-1150 DEG C; and (5) carrying out thermal compression processing with the deformation of 70% at the strain rate of 1-10s <-1 >, and then carrying out water-cooling quenching to obtain a finished product. According to the invention, hot compression processing is carried out in a large deformation manner, and uniform and fine recrystallized equiaxed grains with good hot working performance and corrosion resistance are obtained.

Description

Technical Field

[0001] This invention belongs to the field of stainless steel hot working technology, and relates to a method for improving the corrosion resistance of high-nitrogen austenitic stainless steel. Background Technology

[0002] The high-nitrogen austenitic stainless steel 5Cr21Mn9Ni4N involved in this invention maintains excellent high-temperature strength, thermal fatigue resistance, and corrosion resistance. By substituting nitrogen for nickel, it significantly reduces alloy costs, making it widely used in critical components such as exhaust valves for internal combustion engines, combustion chambers for aerospace engines, and petrochemical reactors. However, the high C, Cr, Mn, and N content in this steel, especially the large addition of N, significantly exacerbates the work hardening tendency during hot working, leading to increased deformation resistance, stress concentration, and cracking, thus limiting its hot working window. Furthermore, the presence of nitrogen promotes the precipitation of the hard Cr2N phase, a significant factor contributing to the decreased corrosion resistance of high-nitrogen austenitic stainless steel, particularly increasing the risk of intergranular corrosion. Therefore, improving the corrosion resistance of high-nitrogen austenitic stainless steel is of great significance for overcoming the application limitations of traditional austenitic stainless steel and reducing industrial safety risks.

[0003] Currently, domestic research on the hot compression of high-nitrogen austenitic stainless steel with large deformation is insufficient. Existing studies mostly use 50% deformation for hot compression processing. However, under this condition, the material mainly undergoes dynamic recovery, lacking recrystallization behavior, resulting in coarse grains and poor hot working and corrosion resistance. In contrast, using a 70% deformation amount provides the necessary conditions for complete dynamic recrystallization, helping to reveal how the original coarse grains gradually break down and refine, ultimately forming uniform, fine equiaxed grains. Understanding this law is crucial for controlling product grain size and improving overall mechanical properties. Furthermore, large deformation hot working has significant advantages in process control. On the one hand, by precisely controlling process parameters, sufficient dynamic recrystallization can be promoted under large deformation conditions. The recrystallization softening effect can counteract work hardening, thereby reducing deformation resistance, alleviating stress concentration, and fundamentally inhibiting the generation of hot cracks. On the other hand, combined with optimized process design, large deformation helps to obtain a fine and uniform recrystallized structure, effectively controlling the formation of harmful precipitates, reducing component segregation, and improving the material's corrosion resistance. These improvements in microstructure directly translate into increased product strength, plasticity, and fatigue life, meeting the stringent material performance requirements of high-end components such as engine valves. Furthermore, the widespread adoption of this method helps reduce the frequency of trial and error in the production process, significantly lowering scrap and rework rates, thereby saving production and time costs and enhancing industrial competitiveness.

[0004] Therefore, this invention aims to provide a method for improving the corrosion resistance of high-nitrogen austenitic stainless steel. The core objective of this method is to obtain an excellent hot-working microstructure by precisely controlling thermodynamic parameters, thereby significantly improving its hot-working plasticity and corrosion resistance. Based on this, the method can safely achieve greater deformation processing, ultimately shortening the production cycle and reducing overall production costs. Summary of the Invention

[0005] To address the problems existing in the background art, the present invention provides a method for improving the corrosion resistance of high-nitrogen austenitic stainless steel. To achieve the above objectives, the technical solution adopted by the present invention is as follows: The processing method includes the following steps: (1) Prepare high-nitrogen austenitic stainless steel raw materials according to the formula, and refine high-nitrogen austenitic stainless steel in a vacuum melting furnace to obtain high-nitrogen austenitic stainless steel billet, and then perform pre-forging treatment. After pre-forging, water cooling is used to obtain pre-forged plate. (2) The pre-forged plate obtained in step (1) is subjected to solution heat treatment using a box-type resistance furnace and then water-cooled to obtain the solution heat-treated material. (3) The solution heat-treated material obtained in step (2) is processed to obtain a hot-compressed sample; (4) The hot-compressed sample in step (3) is subjected to tissue homogenization treatment at 1200℃ and kept at that temperature for 5 minutes; (5) Cool the sample from step (4) to a deformation temperature of 1050-1150℃; (6) Immediately at 1050-1150℃, with a strain rate of 1-10s -1 The high-nitrogen austenitic stainless steel product is obtained by hot compression processing with a deformation of 70% and then quenching.

[0006] As a preferred embodiment of the present invention, the chemical composition of the high-nitrogen austenitic stainless steel formulation, by mass percentage, is as follows: C: 0.48-0.58%, Cr: 20.0-22.0%, Mn: 8.0-10.0%, Ni: 3.25-4.5%, N: 0.35%-0.50%, Si≤0.35%, P: ≤0.04%, S: ≤0.03%, with the balance being Fe and unavoidable impurities.

[0007] As a preferred embodiment of the present invention, in step (1), the initial forging temperature of the pre-forging treatment is controlled at 900-1150°C, the final forging temperature is ≥850°C, and the forging ratio is 4-6.

[0008] As a preferred embodiment of the present invention, in step (2), the solution temperature is 1150℃, the solution time is 60min, and the solution treatment water cooling is room temperature water cooling quenching.

[0009] As a preferred embodiment of the present invention, in step (3), the solid solution material is mechanically wire-cut into a hot-compressed sample with a diameter of 8 mm and a height of 12 mm.

[0010] As a preferred embodiment of the present invention, in step (4), the hot-compressed sample is heated to 1200°C at a heating rate of 5°C / s and kept at that temperature for 5 minutes to perform tissue homogenization treatment.

[0011] In a preferred embodiment of the present invention, in step (5), after homogenization treatment of the tissue, it is cooled to the deformation temperature at a cooling rate of 10°C / s.

[0012] In a preferred embodiment of the present invention, in step (6), the product is immediately subjected to a temperature of 1050–1150°C for 1–10 seconds. -1 The strain rate was subjected to hot compression processing, and the deformation was 70%.

[0013] The beneficial effects of this invention are as follows: (1) The present invention uses a large deformation hot compression processing method to process high nitrogen austenitic stainless steel, and controls the processing parameters by strain rate and deformation temperature, so that high nitrogen austenitic stainless steel can obtain a fine and uniform hot deformation structure with stable performance.

[0014] (2) This invention achieves solid solution strengthening and inhibits the formation of precipitates through hot compression processing with large deformation. Compared with the traditional deformation amount (50%), which leads to a decrease in the corrosion resistance of the material after hot compression, and the problem of poor intergranular corrosion resistance of austenitic stainless steel after hot deformation, this invention obtains a good hot deformation structure and significantly improves the intergranular corrosion resistance by adjusting the processing technology, thereby improving the corrosion resistance of the material.

[0015] (3) The present invention significantly reduces the number of processing passes and intermediate heat treatment steps through the large deformation hot compression process, greatly shortens the production cycle and adapts to large-scale batch production; the process simultaneously reduces energy consumption and raw material loss, increases the billet yield, and reduces the cost of subsequent repair and cleaning processes. Attached Figure Description

[0016] Figure 1 The rheological curves of Example 1 at a deformation temperature of 1150℃ and different strain rates are shown.

[0017] Figure 2 The microstructure of the sample after hot compression in Example 1 is shown in (a) at 0.01 s. -1 / 1150℃; (b) is 0.1s -1 / 1150℃; (c) is 1s -1 / 1150℃; (d) is 10s -1 / 1150℃.

[0018] Figure 3 (a) is the DL-EPR curve of Example 1 after hot compression; (b) is the comparison curve of intergranular corrosion resistance of Example 1.

[0019] Figure 4 The rheological curves of Example 2 at a deformation temperature of 1050℃ and different strain rates are shown.

[0020] Figure 5 The microstructure of the sample after hot compression in Example 2 is shown in (a) at 0.01 s. -1 / 1050℃; (b) is 0.1s -1 / 1050℃; (c) is 1s -1 / 1050℃; (d) is 10s -1 / 1050℃.

[0021] Figure 6 (a) is the DL-EPR curve of Example 2 after hot compression; (b) is the comparison curve of intergranular corrosion resistance of Example 2.

[0022] Figure 7 Example 3 at 10s -1 Rheological curves at different deformation temperatures under different strain rates.

[0023] Figure 8 The microstructure of the sample after hot compression in Example 3 is shown in (a) at 10 s. -1 (a) 850℃; (b) 10s -1 / 950℃; (c) is 10s -1 / 1050℃; (d) is 10s -1 / 1150℃.

[0024] Figure 9 (a) is the DL-EPR curve of Example 3 after hot compression; (b) is the comparison curve of intergranular corrosion sensitivity of Example 3.

[0025] Figure 10 Example 4 at 1s -1 Rheological curves at different deformation temperatures under different strain rates.

[0026] Figure 11 The microstructure of the sample after hot compression in Example 4 is shown in (a) as 1s. -1 / 850℃; (b) is 1s -1 / 950℃; (c) is 1s -1 / 1050℃; (d) is 1s -1 / 1150℃.

[0027] Figure 12 (a) is the DL-EPR curve of Example 4 after hot compression; (b) is the comparison curve of intergranular corrosion sensitivity of Example 4.

[0028] Figure 13 This is a hot working diagram of high-nitrogen austenitic stainless steel with a deformation of 70% (true strain = 1.2). Detailed Implementation

[0029] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, but the scope of protection of the present invention is not limited to the content described.

[0030] The embodiments and comparative examples of the present invention are obtained through single-pass hot compression deformation of high-nitrogen austenitic stainless steel. The hot working diagram is drawn using true stress-strain data. Based on the control of strain rate and deformation temperature, the hot deformation behavior of high-nitrogen austenitic stainless steel is predicted.

[0031] The intergranular corrosion resistance of the embodiments and comparative examples of the present invention was tested by the double-ring electrochemical potential reactivation method. The intergranular corrosion solution was 1.2 mol H2SO4 + 1 mol NaCl + 0.03 mol KSCN. The scanning range was -400 mV to 700 mV, and the scanning rate was 0.1 V / s. The intergranular corrosion sensitivity Ra of the material was the ratio of the reactivation peak Ir to the activation peak Ia, i.e. Ra = (Ir / Ia) × 100%.

[0032] Example 1 The chemical composition of the high-nitrogen austenitic stainless steel formulation described in this embodiment, by mass percentage, is as follows: C: 0.5%, Cr: 21.7%, Mn: 9.4%, Ni: 3.6%, N: 0.43%, Si≤0.35%, P: ≤0.04%, S: ≤0.03%, with the balance being Fe and unavoidable impurities.

[0033] (1) High-nitrogen austenitic stainless steel was melted in a 50kg vacuum melting furnace to obtain a billet.

[0034] (2) The billet is pre-forged. The initial forging temperature of the pre-forging process is controlled at 1000℃, the final forging temperature is 850℃, the forging ratio is 5, and then the pre-forged plate is obtained by water cooling.

[0035] (3) The pre-forged plate is subjected to solution heat treatment at a temperature of 1150℃ for 60 min and then water-cooled (room temperature water quenching) to obtain the solution heat-treated material.

[0036] (4) The solid solution material is mechanically wire-cut into a hot-compression sample with a diameter of 8 mm and a height of 12 mm.

[0037] (5) A single-pass hot compression simulation test was conducted on high-nitrogen austenitic stainless steel using a Gleeble-3500 thermal simulation tester. The hot compression sample was heated to 1200℃ at a heating rate of 5℃ / s, held for 5 min, and then cooled to the deformation temperature of 1150℃ at a cooling rate of 10℃ / s.

[0038] (6) Under the conditions of deformation temperature of 1150℃ and deformation of 70%, the strain rate was set to 0.01s. -1 0.1s -1 1s -1 10s -1 The samples were subjected to hot compression processing to obtain four specimens. The corrosion resistance properties are shown in Table 1. Table 1 From Table 1 and Figure 3 It can be seen that, at a deformation temperature of 1150℃, the intergranular corrosion susceptibility value Ra decreases with increasing strain rate. Ra is a quantitative indicator characterizing intergranular corrosion, reflecting the difference in corrosion rate and susceptibility between intergranular and intragranular areas. The smaller the Ra value, the lower the tendency for intergranular corrosion and the better the corrosion resistance. This indicates that increasing the strain rate, especially at a strain rate of 1 s², is beneficial. -1 and 10s -1 This is beneficial for improving the corrosion resistance of materials.

[0039] Depend on Figure 1 It can be seen from the stress-strain curve under the deformation temperature condition of 1150℃ that the peak stress continuously increases with the increase of strain rate; at 0.01s -1 At the strain rate, the rheological curve shows fluctuations, indicating a significant competition between work hardening and softening, and incomplete material recrystallization; at 0.1s... -1 At the strain rate, the rheological curve reaches its peak and then shows a downward trend, indicating that the material mainly undergoes dynamic recovery softening; at 1s -1 At the strain rate, there is a clear dynamic recrystallization phenomenon, but the rheological curve rises suddenly at large strain, indicating that the recrystallization process is suppressed; at 10s -1 At the strain rate, the rheological curve reaches its peak and then gradually declines to a stable state, indicating that the recrystallization process is relatively complete and the material has good properties.

[0040] Depend on Figure 2 It can be seen that under a deformation temperature of 1150℃, the number of austenite recrystallized grains increases continuously with the increase of strain rate, especially at 1s. -1and 10s -1 Under different strain rates, the recrystallization of austenite results in an increase in equiaxed grains, which are finer and more uniform.

[0041] Example 2 The chemical composition of the high-nitrogen austenitic stainless steel formulation described in this embodiment, by mass percentage, is as follows: C: 0.5%, Cr: 21.7%, Mn: 9.4%, Ni: 3.6%, N: 0.43%, Si≤0.35%, P: ≤0.04%, S: ≤0.03%, with the balance being Fe and unavoidable impurities.

[0042] (1) High-nitrogen austenitic stainless steel was melted in a 50kg vacuum melting furnace to obtain a billet.

[0043] (2) The billet is pre-forged. The initial forging temperature of the pre-forging process is controlled at 1000℃, the final forging temperature is 850℃, the forging ratio is 5, and then the pre-forged plate is obtained by water cooling.

[0044] (3) The pre-forged plate is subjected to solution heat treatment at a temperature of 1150℃ for 60 min and then water-cooled (room temperature water quenching) to obtain the solution heat-treated material.

[0045] (4) The solid solution material is mechanically wire-cut into a hot-compression sample with a diameter of 8 mm and a height of 12 mm.

[0046] (5) A single-pass hot compression simulation test was conducted on high-nitrogen austenitic stainless steel using a Gleeble-3500 thermal simulation tester. The hot compression sample was heated to 1200℃ at a heating rate of 5℃ / s, held for 5 min, and then cooled to the deformation temperature of 1050℃ at a cooling rate of 10℃ / s.

[0047] (6) Under the conditions of deformation temperature of 1050℃ and deformation of 70%, the strain rate was set to 0.01s. -1 0.1s -1 1s -1 10s -1 The samples were subjected to hot compression processing to obtain four specimens. The corrosion resistance properties are shown in Table 2. Table 2 From Table 2 and Figure 6 It can be seen that, at a deformation temperature of 1050℃, the intergranular corrosion susceptibility value Ra decreases with increasing strain rate; this indicates that increasing the strain rate, especially at a strain rate of 1s... -1 and 10s -1 This is beneficial for improving the corrosion resistance of materials.

[0048] Depend on Figure 4It can be seen that the stress-strain curve under the deformation temperature condition of 1050℃, at 0.01s -1 At the strain rate, the rheological curve reaches its peak and then declines, indicating that the stress decrease is caused by the synergistic effect of intensified dynamic recovery and dynamic recrystallization; at 0.1 s⁻¹... -1 At high strain rates, significant fluctuations are observed, with the curve showing a downward trend, indicating that the material primarily exhibits dynamic recovery; at 1s... -1 At the strain rate, there is a clear dynamic recrystallization phenomenon, but the rheological curve rises suddenly at large strain, indicating that the recrystallization process is suppressed; at 10s -1 At the strain rate, the rheological curve quickly reaches its peak and then tends to stabilize, indicating that the recrystallization process is relatively complete and the material has good properties.

[0049] Depend on Figure 5 It can be seen that under a deformation temperature of 1050℃, the austenite recrystallized grains continuously grow with increasing strain rate, especially at 1s. -1 and 10s -1 Under different strain rates, the austenite grains are refined, the deformed grains are reduced, and the recrystallized equiaxed grains are increased, resulting in better material properties.

[0050] Example 3 The chemical composition of the high-nitrogen austenitic stainless steel formulation described in this embodiment, by mass percentage, is as follows: C: 0.5%, Cr: 21.7%, Mn: 9.4%, Ni: 3.6%, N: 0.43%, Si≤0.35%, P: ≤0.04%, S: ≤0.03%, with the balance being Fe and unavoidable impurities.

[0051] (1) High-nitrogen austenitic stainless steel was melted in a 50kg vacuum melting furnace to obtain a billet.

[0052] (2) The billet is pre-forged. The initial forging temperature of the pre-forging process is controlled at 1000℃, the final forging temperature is 850℃, the forging ratio is 5, and then the pre-forged plate is obtained by water cooling.

[0053] (3) The pre-forged plate is subjected to solution heat treatment at a temperature of 1150℃ for 60 min and then water-cooled (room temperature water quenching) to obtain the solution heat-treated material.

[0054] (4) The solid solution material is mechanically wire-cut into a hot-compression sample with a diameter of 8 mm and a height of 12 mm.

[0055] (5) A single-pass hot compression simulation test was conducted on high-nitrogen austenitic stainless steel using a Gleeble-3500 thermal simulation tester. The hot compression sample was heated to 1200℃ at a heating rate of 5℃ / s, held for 5 min, and then cooled to the deformation temperature at a cooling rate of 10℃ / s.

[0056] (6) Under different deformation temperature conditions: 850℃, 950℃, 1050℃, 1150℃, strain rate of 10s -1 The deformation was 70%, and hot compression processing was performed; four samples were obtained, and their corrosion resistance is shown in Table 3. Table 3 From Table 3 and Figure 9 It can be seen that at a strain rate of 10s -1 Under these conditions, the intergranular corrosion susceptibility value Ra is significantly affected by the deformation temperature. This indicates that increasing the deformation temperature, especially at 1050℃ and 1150℃, is beneficial for improving the corrosion resistance of the material.

[0057] Depend on Figure 7 It can be seen that at a strain rate of 10s -1 The stress-strain curves under the given conditions show that the peak stress is highest at a deformation temperature of 850℃. As the temperature increases, the peak stress and peak strain continuously decrease. This indicates that increasing the temperature favors dynamic recrystallization softening. Furthermore, better recrystallization stability can be achieved at 1050℃ and 1150℃, indicating that the material exhibits good dynamic recrystallization softening characteristics.

[0058] Depend on Figure 8 It can be seen that the strain rate is 10s. -1 Under these conditions, as the deformation temperature increases, the number of recrystallized austenite grains continuously increases, while the number of recovery deformation grains continuously decreases, and the austenite grains are significantly refined. Especially at deformation temperatures of 1050℃ and 1150℃, the austenite grains are significantly refined, the number of recrystallized equiaxed grains increases, the grain refinement is uniform, and the material exhibits good properties.

[0059] Example 4 The chemical composition of the high-nitrogen austenitic stainless steel formulation described in this embodiment, by mass percentage, is as follows: C: 0.5%, Cr: 21.7%, Mn: 9.4%, Ni: 3.6%, N: 0.43%, Si≤0.35%, P: ≤0.04%, S: ≤0.03%, with the balance being Fe and unavoidable impurities.

[0060] (1) High-nitrogen austenitic stainless steel was melted in a 50kg vacuum melting furnace to obtain a billet.

[0061] (2) The billet is pre-forged. The initial forging temperature of the pre-forging process is controlled at 1000℃, the final forging temperature is 850℃, the forging ratio is 5, and then the pre-forged plate is obtained by water cooling.

[0062] (3) The pre-forged plate is subjected to solution heat treatment at a temperature of 1150℃ for 60 min and then water-cooled (room temperature water quenching) to obtain the solution heat-treated material.

[0063] (4) The solid solution material is mechanically wire-cut into a hot-compression sample with a diameter of 8 mm and a height of 12 mm.

[0064] (5) A single-pass hot compression simulation test was conducted on high-nitrogen austenitic stainless steel using a Gleeble-3500 thermal simulation tester. The hot compression sample was heated to 1200℃ at a heating rate of 5℃ / s, held for 5 min, and then cooled to the deformation temperature at a cooling rate of 10℃ / s.

[0065] (6) Under different deformation temperature conditions: 850℃, 950℃, 1050℃, 1150℃, strain rate of 1s -1 The deformation was 70%, and the samples were subjected to hot compression processing; four samples were obtained, and their corrosion resistance is shown in Table 4. Table 4 From Table 4 and Figure 12 It can be seen that at a strain rate of 1s -1 Under these conditions, the intergranular corrosion susceptibility value Ra is significantly affected by the deformation temperature. This indicates that increasing the deformation temperature, especially at 1050℃ and 1150℃, is beneficial for improving the corrosion resistance of the material.

[0066] Depend on Figure 10 It can be seen that at a strain rate of 1s -1 The stress-strain curves under the given conditions show that the peak stress of the rheological curve is the largest at a deformation temperature of 850℃, and the stress continues to rise under large strain. This indicates that work hardening and dynamic recovery softening are significant under low deformation temperature conditions. At 1050℃ and 1150℃, less strain is required to reach the peak stress, and the recrystallization softening process is stable, which is conducive to dynamic recrystallization.

[0067] Depend on Figure 11 It can be seen that the strain rate is 1s -1 Under these conditions, as the deformation temperature increases, the number of austenite recrystallized grains increases continuously, and the austenite grains are significantly refined. At a deformation temperature of 1050℃, the recrystallized grains are small, but when the temperature is raised to 1150℃, the recrystallized grains grow and become more uniform, and the number of equiaxed recrystallized grains increases, resulting in better material properties.

[0068] Depend on Figure 13It can be seen that in the hot working diagram with a true strain of 1.2, the contour lines represent the energy dissipation rate, the shaded area is the rheological instability region, and the white area is the safe processing region; a higher power dissipation efficiency corresponds to the high energy consumption characteristics of microstructure evolution, which usually indicates the occurrence of dynamic recrystallization; when the deformation temperature is in the range of 1050-1150℃ and the strain rate is 1-10s... -1 At this time, the power dissipation efficiency remains at a high level, the thermal activation energy required for dynamic recrystallization is sufficient, and the microstructure exhibits significant dynamic recrystallization morphology characteristics; therefore, the optimal hot working range for high-nitrogen austenitic stainless steel is a temperature of 1050℃~1150℃ and a strain rate of 1~10s. -1 .

[0069] In summary, by controlling the strain rate and deformation temperature under a large deformation of 70%, the material can obtain fine, uniform equiaxed grains with good hot working properties and good corrosion resistance.

[0070] Finally, it should be noted that the scope of protection of this invention is not limited to the above preferred embodiments. Those skilled in the art can make various modifications or adjustments to the specific implementation of the technical solution without departing from the essential spirit and principles of this invention, and these modifications still fall within the protection scope of the claims of this invention.

Claims

1. A method for improving the corrosion resistance of high-nitrogen austenitic stainless steel, characterized in that, By adjusting the process and controlling the strain rate and deformation temperature, products with excellent hot working properties and good corrosion resistance can be obtained, including the following steps: (1) Prepare high-nitrogen austenitic stainless steel raw materials according to the formula, and refine high-nitrogen austenitic stainless steel in a vacuum melting furnace to obtain high-nitrogen austenitic stainless steel billet, and then perform pre-forging treatment. After pre-forging, water cooling is used to obtain pre-forged plate. (2) The pre-forged plate obtained in step (1) is subjected to solution heat treatment using a box-type resistance furnace and then water-cooled to obtain the solution heat-treated material. (3) The solution heat-treated material obtained in step (2) is processed to obtain a hot-compressed sample; (4) The hot-compressed sample in step (3) is subjected to tissue homogenization treatment; (5) Cool the sample from step (4) to a deformation temperature of 1050-1150℃; (6) At strain rates of 1–10 s -1 The high-nitrogen austenitic stainless steel product is obtained by hot compression processing with a deformation of 70% and then quenching.

2. The method for improving the corrosion resistance of high-nitrogen austenitic stainless steel according to claim 1, characterized in that: The chemical composition of the high-nitrogen austenitic stainless steel formulation, by mass percentage, is as follows: C: 0.48–0.58%, Cr: 20.0–22.0%, Mn: 8.0–10.0%, Ni: 3.25–4.5%, N: 0.35%–0.50%, Si ≤ 0.35%, P: ≤ 0.04%, S: ≤ 0.03%, with the balance being Fe and unavoidable impurities.

3. The method for improving the corrosion resistance of high-nitrogen austenitic stainless steel according to claim 1, characterized in that: In step (1), the initial forging temperature of the pre-forging treatment is controlled at 900-1150℃, the final forging temperature is ≥850℃, and the forging ratio is 4-6.

4. The method for improving the corrosion resistance of high-nitrogen austenitic stainless steel according to claim 1, characterized in that: In step (2), the solution temperature is 1150℃, the solution time is 60min, and the solution treatment water cooling is room temperature water cooling quenching.

5. The method for improving the corrosion resistance of high-nitrogen austenitic stainless steel according to claim 1, characterized in that: In step (4), the conditions for tissue homogenization are as follows: the hot-compressed sample is heated to 1200°C at a heating rate of 5°C / s and kept at that temperature for 5 minutes to perform tissue homogenization.

6. The method for improving the corrosion resistance of high-nitrogen austenitic stainless steel according to claim 1, characterized in that: In step (5), after homogenization, the tissue is cooled to the deformation temperature at a cooling rate of 10℃ / s.

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