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CN-122007404-A - Rolling contact damage-resistant nano ceramic particle reinforced steel for train wheels and preparation method thereof

CN122007404ACN 122007404 ACN122007404 ACN 122007404ACN-122007404-A

Abstract

The invention provides rolling contact damage resistant nano ceramic particle reinforced steel for train wheels and a preparation method thereof, and belongs to the technical field of preparation of steel for train wheels. The steel for the wheels is prepared by mixing Al powder, ti powder and multi-wall carbon nano tubes to obtain mixed powder, ball milling, cold press molding and hot press sintering to obtain TiC/Al intermediate alloy, crushing the TiC/Al intermediate alloy into alloy scraps, placing the alloy scraps at the bottom of a steel ladle, tapping molten steel for the wheels into the steel ladle, and carrying out vacuum degassing refining, continuous casting, forging and heat treatment. According to the invention, the TiC/Al intermediate alloy carrier introduction method is adopted, so that the problems of particle agglomeration, segregation, floating or sedimentation and the like caused by poor wettability and density difference when nano particles are directly added are effectively avoided, the TiC/Al intermediate alloy carrier introduction improves the rolling contact damage resistance of the wheel steel, and the high performance requirement of modern rail transit on the wheel steel is met.

Inventors

  • BAI ZHIXIONG
  • LIU YANSHENG
  • SHEN MINGXUE
  • JI DEHUI

Assignees

  • 华东交通大学

Dates

Publication Date
20260512
Application Date
20260413

Claims (10)

  1. 1. The preparation method of the rolling contact damage resistant nano ceramic particle reinforced steel for the train wheels is characterized by comprising the following steps of: (1) Mixing Al powder, ti powder and multi-wall carbon nano tubes to obtain mixed powder, and performing ball milling, cold press molding, hot press sintering to obtain TiC/Al intermediate alloy; (2) Crushing the TiC/Al intermediate alloy obtained in the step (1) into alloy scraps, placing the alloy scraps at the bottom of a steel ladle, tapping steel liquid for the wheel to the steel ladle, and performing primary refining, vacuum degassing refining, continuous casting, forging and heat treatment to obtain the steel for the wheel.
  2. 2. The method for preparing the rolling contact damage resistant nano ceramic particle reinforced steel for train wheels, according to claim 1, wherein the mass fraction of Ti powder in the mixed powder is 20-30%, the mass fraction of multi-wall carbon nano tube powder is 2-10%, and the balance is Al powder.
  3. 3. The method for preparing the rolling contact damage resistant nano ceramic particle reinforced steel for train wheels according to claim 1, wherein the hot press sintering is performed under a protective atmosphere at a pressure of 10-50 MPa and a temperature of 850-950 ℃.
  4. 4. The method for preparing rolling contact damage resistant nano ceramic particle reinforced steel for train wheels according to claim 1, wherein the particle size of the alloy scraps is less than 5mm.
  5. 5. The method for preparing rolling contact damage resistant nano ceramic particle reinforced steel for wheels of trains according to claim 1, wherein the alloy scraps accounts for 0.02-0.20wt.% of the mass of the steel liquid for wheels.
  6. 6. The preparation method of the rolling contact damage resistant nano ceramic particle reinforced steel for the wheels of the train, which is characterized in that the steel liquid for the wheels comprises ：C 0.65～0.72%,Si 0.80～0.90%,Mn 0.90～1.00%,P≤0.018%,S≤0.018%,Cr 0.10～0.20%,V 0.03～0.06%,Mo 0.04～0.07%,Cu 0.20～0.27%,Ti 0.01～0.10%,Ni 0.16～0.20%, mass percent of Cr+Mo+Ni which is less than or equal to 0.50 mass percent, and the balance of Fe and unavoidable impurities.
  7. 7. The method for preparing the rolling contact damage resistant nano ceramic particle reinforced steel for the train wheels, which is disclosed in claim 1, is characterized in that the tapping temperature is 1520-1680 ℃, the initial refining temperature is 1500-1700 ℃ and the time is 50-60 min, and the vacuum degassing refining temperature is 1550-1600 ℃ and the time is 20-30 min.
  8. 8. The method for preparing the rolling contact damage resistant nano ceramic particle reinforced steel for train wheels, according to claim 1, wherein the heating temperature of forging is 1200-1300 ℃, and the forging ratio is more than or equal to 4.
  9. 9. The method for preparing the rolling contact damage resistant nano ceramic particle reinforced steel for train wheels according to claim 1, wherein the heat treatment is heating to 850-890 ℃, preserving heat for 2-3 hours, quenching at 510-540 ℃, and tempering at 350-500 ℃.
  10. 10. The rolling contact damage resistant nano ceramic particle reinforced steel for train wheels is characterized by being prepared by the preparation method according to any one of claims 1-9.

Description

Rolling contact damage-resistant nano ceramic particle reinforced steel for train wheels and preparation method thereof Technical Field The invention belongs to the technical field of preparation of steel for train wheels, and particularly relates to rolling contact damage resistant nano ceramic particle reinforced steel for train wheels and a preparation method thereof. Background As rail traffic continues to evolve toward high speed, heavy loads, critical load bearing components such as train wheels face unprecedented challenges. At present, most of high-performance steel development for train wheels still uses traditional metal material strengthening and toughening approaches, such as component design, microalloying, tissue regulation and control and the like, but the performance optimization effect of the steel is not obviously broken through, which clearly shows that the traditional component optimization and tissue regulation and control method has obvious bottleneck for improving the performance of the wheel materials. Aiming at the wheel material strengthening bottleneck, a metal material toughening technology based on nano ceramic particles is attracting great attention. Different from the traditional component regulation and control technology, the technology is characterized in that nano ceramic particles are introduced in the smelting process, an as-cast structure is regulated and controlled by means of a heterogeneous nucleation mechanism, and the pinning and nucleation site functions are exerted in a second phase particle form in a subsequent structure regulation and control link, so that the refinement and uniform distribution of a microstructure are finally realized. Although a proper amount of nano particles can effectively improve the comprehensive performance of the material, the direct addition mode still has obvious limitation that the wettability between the nano ceramic particles and molten steel is poor, and the nano ceramic particles and the molten steel have density difference, so that the nano ceramic particles are difficult to uniformly distribute in the molten steel. Therefore, how to break through the technical limitation of the existing adding mode, fundamentally improve the wettability and dispersion stability of the nano ceramic particles in the melt, realize the uniform and dispersion distribution of the nano ceramic particles in the steel matrix for the wheel, and become a key bottleneck for pushing the technology to large-scale engineering application. Based on the above, the invention aims to provide a method capable of effectively solving the problems, so as to realize the efficient and uniform introduction of nano ceramic particles in a steel matrix for the wheel, thereby fully playing the strengthening effect and meeting the severe requirements of high-end wheels on comprehensive performance. Disclosure of Invention Aiming at solving the core problems that the nano ceramic reinforcing phase is difficult to uniformly disperse in a steel matrix due to poor wettability and easy agglomeration in the prior art, the invention provides a rolling contact damage-resistant nano ceramic particle reinforced steel for train wheels and a preparation method thereof, the invention adopts a composite process of in-situ synthesis and metal carrier transition, the TiC/Al intermediate alloy scraps containing the nano ceramic particles are prepared in advance and introduced into molten steel, the Al matrix is melted in the molten steel by utilizing the upward-downward rising and convection actions of the molten steel, steel slag is generated by reacting with oxygen in the molten steel and floats on the surface of the molten steel, and the released TiC particles are uniformly dispersed in the steel matrix, so that the high-efficiency and uniform introduction of the reinforcing phase is realized, and the rolling contact damage resistance of the steel for the wheels is remarkably improved. In order to achieve the above purpose, the present invention provides the following technical solutions: the invention provides a preparation method of rolling contact damage resistant nano ceramic particle reinforced steel for train wheels, which comprises the following steps: (1) Mixing Al powder, ti powder and multi-wall carbon nano tubes to obtain mixed powder, and performing ball milling, cold press molding, hot press sintering to obtain TiC/Al intermediate alloy; (2) Crushing the TiC/Al intermediate alloy obtained in the step (1) into alloy scraps, placing the alloy scraps at the bottom of a steel ladle, tapping steel liquid for the wheel to the steel ladle, and performing primary refining, vacuum degassing refining, continuous casting, forging and heat treatment to obtain the steel for the wheel. The invention prepares TiC/Al intermediate alloy by ball milling, cold pressing and hot pressing sintering of Al powder, ti powder and multiwall carbon nano tube, synthesizes TiC nano particles in situ by u