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CN-122013172-A - TiC-SiC synergic enhancement 304 stainless steel composite coating based on high-speed laser cladding and preparation method thereof

CN122013172ACN 122013172 ACN122013172 ACN 122013172ACN-122013172-A

Abstract

The application relates to a TiC-SiC reinforced 304 stainless steel composite coating based on high-speed laser cladding and a preparation method thereof. A composite coating with 304 stainless steel as a metal matrix phase and TiC and SiC as ceramic reinforcing phases is prepared on the surface of a steel matrix by adopting a high-speed laser cladding technology. In the cladding process, tiC ceramic particles keep stable structure, controllable partial decomposition is carried out on the SiC ceramic particles, si elements released by decomposition form Si enrichment areas at interfaces of the ceramic particles and the metal matrix, and C elements released by decomposition react with the metal matrix to generate carbide phases. Therefore, the composite coating with compact structure and good interface combination is obtained, and is suitable for protecting the surface of the steel member serving under the working condition of coupling abrasion and corrosion.

Inventors

  • CHEN SHUISHENG
  • CHEN QIAN
  • YANG LIUHUA
  • ZHANG NANNAN
  • ZHOU YANG
  • QI JINLONG
  • ZHOU MINGWEI

Assignees

  • 河南理工大学

Dates

Publication Date
20260512
Application Date
20260202

Claims (8)

  1. 1. TiC-SiC synergic enhancement 304 stainless steel composite coating based on high-speed laser cladding is characterized in that: The composite coating is prepared on the surface of a steel matrix in a high-speed laser cladding mode and comprises a 304 stainless steel metal matrix phase which is continuously distributed, and TiC ceramic particles and SiC ceramic particles which are distributed in the metal matrix phase in a dispersed manner, wherein the sum of the mass percentages of TiC, siC and 304 stainless steel is 100%; Under the conditions of high energy density and rapid fusion of high-speed laser cladding, tiC ceramic particles keep stable structure in the cladding process and basically do not decompose or melt, and are present in the composite coating as a main bearing hard reinforcing phase; The SiC ceramic particles are subjected to controllable partial decomposition and not subjected to complete decomposition under the high-speed laser cladding condition, si elements released by decomposition in the partial decomposition process form a local Si enrichment zone in an interface area of the SiC ceramic particles and the 304 stainless steel metal matrix phase, and the Si enrichment zone covers or coats at least part of the interface surface of the SiC ceramic particles and is used for improving the interface bonding state between the SiC ceramic particles and the 304 stainless steel metal matrix phase; Meanwhile, C element released by decomposition in the partial decomposition process enters a metal matrix phase and reacts with Fe element in the metal matrix phase to form carbide phases in discrete distribution in the composite coating.
  2. 2. The composite coating of claim 1, wherein the coating is a coating, The TiC ceramic particles are distributed in the 304 stainless steel metal matrix phase in a dispersion manner, and form a synergistic enhancement structure with the Si enrichment region in the interface region on a microscopic scale.
  3. 3. The composite coating of claim 1, wherein the coating is a coating, The SiC ceramic particles still keep the particle morphology in the composite coating after cladding, the characteristic size of the SiC ceramic particles can be identified in the coating microstructure, and the Si enrichment region is positioned in the adjacent area of the interface of the SiC ceramic particles and the 304 stainless steel metal matrix phase, is distributed in a local continuous or semi-continuous mode, and covers or coats at least part of the surface of the ceramic particles.
  4. 4. The composite coating of claim 1, wherein the coating is a coating, The laser scanning speed adopted by the high-speed laser cladding is 1.5-6.0m/min so as to form a transient molten pool with high energy density and limited action time, thereby realizing the controllable partial decomposition of SiC ceramic particles.
  5. 5. The composite coating of claim 1, wherein the coating is a coating, The mass ratio of TiC to SiC is 1 (0.5-1.0), and the particle size of TiC ceramic particles and SiC ceramic particles is 1-10 mu m.
  6. 6. The composite coating of claim 1, wherein the coating is a coating, The steel matrix is 27SiMn steel, and the composite coating is used for protecting the surface of a hydraulic support upright post or a jack.
  7. 7. The preparation method of the TiC-SiC-304 stainless steel composite coating for realizing interface enhancement by utilizing SiC controllable decomposition is characterized by comprising the following steps: (1) Mixing TiC ceramic powder, siC ceramic powder and 304 stainless steel powder according to a set proportion to obtain composite cladding powder; (2) After the surface of the steel matrix is pretreated, cladding the composite cladding powder on the surface of the steel matrix by adopting a high-speed laser cladding process; (3) Under the conditions of high-speed heating and rapid solidification, the TiC ceramic powder is kept stable in structure, the SiC ceramic powder is partially decomposed, si element released by decomposition forms an Si enrichment area at the interface of the ceramic phase and the metal matrix phase, and C element released by decomposition reacts with Fe element in the metal matrix to generate a carbide phase.
  8. 8. The method according to claim 7, wherein, By regulating the laser power and the scanning speed, the SiC ceramic powder is partially decomposed instead of completely decomposed in the cladding process.

Description

TiC-SiC synergic enhancement 304 stainless steel composite coating based on high-speed laser cladding and preparation method thereof Technical Field The application belongs to the technical field of surface engineering and laser processing, in particular relates to a TiC-SiC synergic enhancement 304 stainless steel composite coating based on high-speed laser cladding and a preparation method thereof, and particularly relates to a composite coating structure and process for realizing ceramic phase and metal matrix interface enhancement by utilizing SiC controllable decomposition, which are suitable for steel member surface enhancement with synergic requirements on wear resistance and corrosion resistance. Background The hydraulic support is key equipment in coal mine safety production, wherein bearing components such as an upright post, a jack and the like are in complex working conditions of high load, reciprocating motion and coexistence of corrosive media for a long time in the service process, the surface of a piston and the inner wall of a cylinder body are easy to be severely worn and corroded, and the service life and the operation safety of equipment are directly affected. Therefore, development of a surface strengthening technology having both excellent wear resistance and corrosion resistance for the above-mentioned critical parts has important engineering significance. Currently, common methods for improving the surface properties of steel members include chrome plating, electroplating, thermal spraying, laser cladding, and the like. The high-speed laser cladding technology has low heat input, small dilution rate, compact coating and good metallurgical bonding with a matrix, and is widely focused in the heavy-load wear-resistant and corrosion-resistant field. Stainless steel materials, particularly 304 stainless steel, have been introduced into laser cladding coating systems with good corrosion resistance. However, the single 304 stainless steel coating has lower hardness, and is difficult to meet the requirement of wear resistance under severe working conditions. To improve the wear resistance of the coating, researchers have attempted to introduce ceramic reinforcing phases, such as TiC or SiC, into the stainless steel coating. TiC has high hardness and good thermal stability, can obviously improve the hardness and wear resistance of the coating, but easily introduces larger thermal stress in the laser cladding process, increases the cracking risk of the coating, and influences the service reliability. SiC has a high hardness and a potential wear-resistant reinforcing effect, but is easily decomposed under the action of high-energy laser, and the reinforcing effect tends to be difficult to fully exert, and may even cause unstable coating structure or performance degradation. The existing research shows that TiC and SiC can show a certain synergistic enhancement effect under the balanced or quasi-balanced process conditions such as sintering and the like. However, high-speed laser cladding has the unbalanced characteristics of rapid melting and rapid solidification, and the TiC, siC and stainless steel substrates show significant differences in thermal stability, reaction behavior and interface evolution mechanism in the process and sintering process. In the prior art, the decomposition of SiC in the laser cladding process is generally regarded as a disadvantageous factor, the effective regulation and utilization of the decomposition behavior of the SiC are lacking, and a stable composite coating scheme capable of simultaneously considering the wear resistance and the corrosion resistance under the high-speed laser cladding condition is not formed. However, the high energy density, short action time, rapid solidification and other unbalanced characteristics of the high-speed laser cladding provide new possibility for regulating and controlling the ceramic phase response behavior. If the controllable partial decomposition of SiC can be generated in the cladding process through reasonable control of cladding process parameters, and the decomposition behavior of the SiC is converted into an advantageous mechanism for improving the interface combination of a ceramic phase and a metal matrix and promoting the formation of an in-situ strengthening phase, the TiC stability strengthening effect is guaranteed, and meanwhile, the comprehensive mechanical property and the corrosion resistance of the composite coating are further improved, so that the service requirements of key equipment such as hydraulic support columns and jacks under the working conditions of heavy load, abrasion and corrosion coupling are met. Disclosure of Invention In order to achieve the aim, the application provides the TiC-SiC synergic reinforcing 304 stainless steel composite coating based on high-speed laser cladding, wherein the composite coating is prepared on the surface of a steel matrix in a high-speed laser cladding mode, 3