Method for improving central precipitated phase of high-alloy stainless steel cold-rolled sheet
By increasing the annealing temperature and accelerating the cooling speed, the problem of Sigma phase residue in the cold-rolled thin sheet of high alloy stainless steel is solved, significantly improving its corrosion resistance and mechanical properties, and improving product quality.
Patent Information
- Application Number
- CN202411939108.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-26
- Publication Date
- 2025-03-28
AI Technical Summary
During the annealing process of cold-rolled thin sheets of high alloy stainless steel, the annealing temperature is too low and the cooling speed is too slow, resulting in Sigma phase residue, reducing the corrosion resistance and mechanical properties of stainless steel.
By increasing the annealing temperature to between 1175°C and 1185°C and cooling quickly after annealing, the cooling rate is controlled between 10°C/sec to 20°C/sec to eliminate internal stress and suppress recrystallization of the Sigma phase.
It effectively reduces the residual of the central Sigma phase, improves the structural structure of high-alloy stainless steel cold-rolled thin plates, improves its corrosion resistance and mechanical properties, and improves product quality.
Smart Images
Figure CN119710205A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to a method for improving the central precipitation phase of a stainless steel cold-rolled thin plate, and in particular to a method for improving the central precipitation phase of a high-alloy stainless steel cold-rolled thin plate. Background Art
[0002] Metal material preparation technology, heat treatment technology and stainless steel materials are very important technical fields in modern manufacturing. Metal material preparation technology mainly uses various processing methods to make metal materials into the required shape and performance. Heat treatment technology changes the internal structure of metal materials to improve their mechanical properties and durability. Stainless steel is a metal material with excellent corrosion resistance and is widely used in aerospace, construction, medical and other fields.
[0003] For the preparation of high alloy (high chromium and high molybdenum alloy, by mass percentage, the chromium content is usually between 20 and 25%, and the molybdenum content is usually between 1 and 6%) stainless steel cold-rolled sheets, a cold rolling annealing process is usually used. Cold rolling is the process of pressing the stainless steel sheet into the required thickness through a rolling mill at room temperature, and annealing is heating the cold-rolled stainless steel sheet to a certain temperature, keeping it for a period of time, and then cooling it at a certain speed to eliminate the internal stress generated during the cold rolling process and improve its organizational structure. However, in the process of preparing high alloy stainless steel cold-rolled sheets, when annealing the high alloy stainless steel cold-rolled sheets, due to the low annealing temperature and slow cooling rate, more Sigma phases are left, and Sigma phases are a kind of intermetallic compound, and the presence of which will reduce the corrosion resistance and mechanical properties of stainless steel. Therefore, how to effectively reduce the residue of Sigma phase in the center of high alloy stainless steel cold-rolled sheets is an important problem currently faced. Summary of the invention
[0004] The technical problem to be solved by the present invention is to provide a method for improving the central precipitation phase of a high-alloy stainless steel cold-rolled sheet which can reduce the residual Sigma phase.
[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is: a method for improving the central precipitation phase of a high-alloy stainless steel cold-rolled sheet, the steps of which include:
[0006] Step 1): preparing a high alloy stainless steel cold rolled sheet;
[0007] Step 2): The high alloy stainless steel cold rolled sheet enters the annealing furnace, and the annealing temperature is adjusted to between 1150°C and 1200°C, and kept warm for more than 3 minutes;
[0008] Step 3): Rapidly cool the annealed high alloy stainless steel cold rolled sheet, with the cooling rate controlled between 10°C / second and 20°C / second until reaching room temperature.
[0009] As a preferred solution, in the method for improving the central precipitation phase of the high-alloy stainless steel cold-rolled sheet, the annealing temperature in step 2) is controlled between 1175°C and 1185°C.
[0010] As a preferred embodiment, in the method for improving the central precipitation phase of the high-alloy stainless steel cold-rolled sheet, the cooling rate in step 3) is controlled between 14°C / sec and 18°C / sec.
[0011] As a preferred embodiment, in the method for improving the central precipitation phase of the high alloy stainless steel cold rolled sheet, the high alloy stainless steel cold rolled sheet is a 31254Mo high alloy stainless steel cold rolled sheet.
[0012] The beneficial effects of the present invention are:
[0013] 1. Increase the annealing temperature: The present invention increases the annealing temperature to between 1175°C and 1185°C, which is higher than the annealing temperature in the prior art. This can more effectively eliminate the internal stress generated during the cold rolling process and promote the decomposition of intermetallic compounds, thereby effectively reducing the residual central Sigma phase.
[0014] 2. Accelerate the cooling rate: After annealing, the present invention accelerates the cooling rate to inhibit the recrystallization and growth of the Sigma phase and further reduce its residue in the central area. This rapid cooling method can effectively shorten the production cycle and improve production efficiency.
[0015] 3. Improve the organizational structure: Through high temperature annealing and rapid cooling, the organizational structure of high alloy stainless steel cold-rolled thin plate can be improved to make it more uniform and dense, thereby improving its corrosion resistance and mechanical properties.
[0016] 4. Improve product quality: Since the present invention can effectively reduce the residual central Sigma phase, the product quality of high-alloy stainless steel cold-rolled thin plates can be improved, making them have better corrosion resistance and mechanical properties, and meet higher standard application requirements.
[0017] 5. Wide application: The technical solution of the present invention is not only applicable to 31254Mo high-alloy stainless steel cold-rolled thin plates, but also to other high-alloy stainless steel cold-rolled thin plates, and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Figure 1 This is a metallographic structure diagram of the product obtained by the first embodiment of the present invention.
[0019] Figure 2 This is a metallographic structure diagram of the product obtained according to the second embodiment of the present invention.
[0020] Figure 3 It is a metallographic structure diagram of the product obtained by the third embodiment of the present invention. DETAILED DESCRIPTION
[0021] The following describes in detail a detailed implementation scheme of a method for manufacturing duplex stainless steel and a sheet thereof according to the present invention in conjunction with the accompanying drawings.
[0022] Embodiment 1:
[0023] The method for improving the central precipitation phase of a high-alloy stainless steel cold-rolled sheet of the present invention comprises the following steps:
[0024] Step 1): preparing a high alloy stainless steel cold-rolled sheet with a thickness of 0.6 mm and a width of 1200 mm;
[0025] Step 2): placing the high alloy stainless steel cold rolled sheet into an annealing furnace, adjusting the annealing temperature to 1180° C., and keeping the temperature for 3 minutes;
[0026] Step 3): The annealed high alloy stainless steel cold rolled sheet is rapidly cooled at a cooling rate of 10°C / s until room temperature, and a sample is taken for metallographic analysis. The central sigma phase accounts for 1.2%. Figure 1 shown.
[0027] Embodiment 2:
[0028] The method for improving the central precipitation phase of a high-alloy stainless steel cold-rolled sheet of the present invention comprises the following steps:
[0029] Step 1): preparing a high alloy stainless steel cold-rolled sheet with a thickness of 0.6 mm and a width of 1200 mm;
[0030] Step 2): placing the high alloy stainless steel cold rolled sheet into an annealing furnace, adjusting the annealing temperature to 1180° C., and keeping the temperature for 3 minutes;
[0031] Step 3): The annealed high alloy stainless steel cold rolled sheet is rapidly cooled at a cooling rate of 13°C / s until room temperature, and a sample is taken for metallographic analysis. The central sigma phase accounts for 0.3%. Figure 2 shown.
[0032] Embodiment three:
[0033] The method for improving the central precipitation phase of a high-alloy stainless steel cold-rolled sheet of the present invention comprises the following steps:
[0034] Step 1): preparing a high alloy stainless steel cold-rolled sheet with a thickness of 0.6 mm and a width of 1200 mm;
[0035] Step 2): placing the high alloy stainless steel cold rolled sheet into an annealing furnace, adjusting the annealing temperature to 1180° C., and keeping the temperature for 3 minutes;
[0036] Step 3): The annealed high alloy stainless steel cold rolled sheet is rapidly cooled at a cooling rate of 16°C / s until room temperature, and a sample is taken for metallographic analysis. The central sigma phase accounts for 0.08%. Figure 3 shown.
[0037] In summary, the above are only preferred embodiments of the present invention and are not intended to limit the scope of implementation of the present invention. Any equivalent changes and modifications made on the basis of the claims of the present invention are within the protection scope of the present invention.
Claims
1. A method for improving the central precipitation phase of a high alloy stainless steel cold-rolled sheet, the steps comprising: Step 1): preparing a high alloy stainless steel cold rolled sheet; Step 2): placing the high alloy stainless steel cold rolled sheet into an annealing furnace, adjusting the annealing temperature to between 1150° C. and 1200° C., and keeping the temperature for more than 3 minutes; Step 3): Rapidly cool the annealed high alloy stainless steel cold rolled sheet, with the cooling rate controlled between 10°C / second and 20°C / second until reaching room temperature.
2. The method for improving the central precipitation phase of a high alloy stainless steel cold-rolled sheet according to claim 1, characterized in that: The annealing temperature in step 2) is controlled between 1175°C and 1185°C.
3. The method for improving the central precipitation phase of a high alloy stainless steel cold-rolled sheet according to claim 1, characterized in that: The cooling rate in step 3) is controlled between 14°C / sec and 18°C / sec.
4. A method for improving the central precipitation phase of a high alloy stainless steel cold rolled sheet according to claim 1, 2 or 3, characterized in that: The high alloy stainless steel cold rolled sheet is a 31254Mo high alloy stainless steel cold rolled sheet.