CN-121992179-A - Method for preparing high-strength high-toughness non-magnetic high-manganese non-magnetic steel through rotary forging and annealing process

Abstract

The invention belongs to the field of plastic forming of metal materials, and particularly relates to a method for preparing high-strength high-toughness non-magnetic high-manganese non-magnetic steel by a rotary forging and annealing process. The method comprises the following steps of (1) carrying out solution treatment on a high-manganese non-magnetic steel bar with a component of Fe-22Mn-1.6Al-0.26C, (2) carrying out rotary swaging, namely carrying out room-temperature rotary swaging on the bar subjected to the solution treatment in the step (1), controlling the deformation of each pass of rotary swaging within 50%, controlling the total deformation of rotary swaging within 90%, and obtaining the bar with 50-nanometer fine crystals, and (3) carrying out annealing treatment on the fine crystal bar obtained in the step (2). The method can prepare the high-manganese non-magnetic steel with high strength, high toughness and ultralow magnetic conductivity, has low cost and strong repeatability, and can be used for mass industrialized production.

Inventors

• ZHAO YONGHAO
• WANG JIAHAO

Assignees

• 南京理工大学

Dates

Publication Date

20260508

Application Date

20241108

Claims (7)

1. 1. A method for preparing high-strength high-toughness non-magnetic high-manganese non-magnetic steel by rotary forging and annealing process is characterized by comprising the following steps: The step (1) is solid solution treatment, which is to carry out solid solution quenching treatment for a high manganese non-magnetic steel bar with the component of Fe-22Mn-1.6Al-0.26C at 1100 ℃ for 120 min; Performing rotary forging treatment, namely performing room-temperature rotary forging on the bar subjected to solution quenching in the step (1), wherein the deformation of each pass of rotary forging is controlled within 50%, and the total deformation of rotary forging treatment is controlled within 90%, so as to obtain the bar with 50 nanometer fine crystals; And (3) annealing treatment, namely carrying out annealing treatment for 12.5min at 600 ℃ on the fine crystal bar obtained in the step (2).
2. 2. The method according to claim 1, wherein the solid solution temperature of the solid solution treatment in the step (1) is higher than the recrystallization temperature and lower than the melting point of the high-manganese non-magnetic steel, and the solid solution time satisfies homogenization of the alloy elements in the rod.
3. 3. The method of claim 2, wherein the cooling in step (1) is furnace cooling.
4. 4. A method according to claim 3, wherein the solid solution treatment in step (1) is carried out by maintaining the bar at 1100 ℃ for 2 hours in a vacuum furnace filled with argon.
5. 5. The method according to claim 4, wherein the temperature of the annealing treatment in the step (3) is controlled to 600 ℃ for 12.5 minutes by cooling at room temperature.
6. 6. The method of claim 1, wherein the high manganese non-magnetic steel bar used in step (1) has a diameter of 36mm.
7. 7. A method for preparing high-strength high-toughness non-magnetic high-manganese non-magnetic steel by rotary forging and annealing process, which is characterized in that the high-manganese non-magnetic steel is prepared by adopting the method of any one of claims 1-6.

Description

Method for preparing high-strength high-toughness non-magnetic high-manganese non-magnetic steel through rotary forging and annealing process Technical Field The invention belongs to the field of plastic forming of metal materials, and particularly relates to a method for preparing high-strength high-toughness non-magnetic high-manganese non-magnetic steel by a rotary forging and annealing process. Background The nonmagnetic steel is a functional steel material widely applied to the engineering field, and can be divided into high-manganese stainless steel and high-manganese nonmagnetic structural steel. In fact, the so-called non-magnetic property is the low permeability of paramagnetic austenitic matrices derived from their face-centered cubic (fcc) structure. In the case of non-magnetic stainless steel, they generally include Cr-Ni, cr-Ni-Mn Cr-Ni-Mn-Mo and Cr-Mn-N alloy system [2], this inevitably increases the material and production costs, so that high Mn non-magnetic steels are generally more widely accepted in the market due to their low price and superior mechanical properties. Therefore, they have wide application in applications requiring structural members to be unaffected by a strong magnetic field or to not interfere with the distribution of an externally applied magnetic field itself, such as concrete reinforcements for low-temperature superconductivity, nuclear fusion reactors, electronic measuring instruments, and radar devices. For non-magnetic steels, the main strategy to achieve low permeability is to ensure stability of the austenitic phase, both during cold working and during heat treatment. However, in the non-magnetic steel field, strength and non-magnetism are difficult to be simultaneously combined, and the combination can be realized only by spending great cost and time. The rotary forging is a near net forming and producing process for processing solid shaft parts or hollow variable cross section forgings by utilizing multi-hammerhead high-speed pulse hammering, and is mainly used for various hollow solid shafts. The rotary forging die is suitable for preparing bars, wires and pipes, in the processing process, the rotary forging die rotates around the outer diameter of a blank at high speed, and radial force is continuously applied to the blank through high-frequency striking, so that the blank is contracted in the radial direction and extends in the axial direction, and meanwhile, the rotary forging die is formed according to the molded line of the die. The material is in a three-way compressive stress state in the rotary forging process, so that cracks generated by severe deformation in the material structure can be welded together by rotary forging, meanwhile, the structure non-uniformity phenomenon generated by non-uniform deformation can be reduced, and the plasticity of the material is improved. Therefore, the rotary forging is particularly suitable for reducing the porosity in powder metallurgy and some metals which are difficult to deform and have poor plasticity. Chinese patent CN101768685A reports that the manufacture of plates and filaments, rods by cold and hot working such as forging, rolling, swaging, drawing, heat treatment, etc., has good biocompatibility and low elastic modulus. The tensile strength of the processed plates and bars is less than or equal to 380MPa, the yield strength is less than or equal to 881MPa, and the elastic modulus is less than or equal to 53GPa. Disclosure of Invention The invention aims to provide a method for preparing high-strength high-toughness non-magnetic high-manganese non-magnetic steel by rotary forging and annealing processes; high-strength high-toughness prepared by rotary forging and annealing process the method of non-magnetic high-manganese non-magnetic steel is that Solution treatment, rotary forging treatment and annealing treatment; carrying out full solid solution treatment on the high-manganese non-magnetic steel bar to homogenize the elements and prevent segregation; carrying out multi-pass rotary forging treatment on the solid-solution bar to obtain a fine crystalline alloy bar; and (3) annealing the bar after the rotary forging to recrystallize the high-manganese non-magnetic steel, so as to obtain the high-manganese non-magnetic steel with high strength, high toughness, low magnetic conductivity, and smooth surface, wherein part of grains of the high-manganese non-magnetic steel are refined, and part of grains of the high-manganese non-magnetic steel grow up. The technical solution for realizing the purpose of the invention is as follows: a method for preparing high-strength high-toughness non-magnetic high-manganese non-magnetic steel by rotary forging and annealing process comprises the following steps: the step (1) is solid solution treatment, which is to carry out solid solution treatment on the high manganese non-magnetic steel bar with the component of Fe-22Mn-1.6 Al-0.26C; Performing rotary forging treatment,