Composite metal carbide wear-resistant coating and preparation process thereof

Abstract

The invention relates to a composite metal carbide wear-resistant coating and a preparation process thereof, and belongs to a wear-resistant coating and a preparation process thereof. The composite metal carbide wear-resistant coating consists of adhesive coated tungsten carbide and other carbides, wherein the adhesive coated tungsten carbide has the grain size of WC-Co or WC-Ni; and the other carbides comprise chromium carbide, vanadium carbide, iron carbide, titanium carbide and the like. The preparation process comprises the following steps of: mixing the adhesive coated tungsten carbide and one or more kinds of the carbide powder; and performing spray coating (welding) or plasma spray coating (welding) on the surface of a medium-carbon steel part through supersonic flame to form the wear-resistant coating, wherein the carbon content of the medium-carbon steel is 0.35 to 0.55 weight percent (wt); the medium-carbon steel is subjected to the thermal refining state of quenching and high-temperature tempering; and the supersonic flame spray coating (welding) or plasma spray coating (welding) process sequentially comprises steps of performing sand blasting and rust removal on the surface of the medium-carbon steel, spraying a Ni-5 percent Al alloy adhesive coating and spraying a composite carbide wear-resistant coating. The composite carbide wear-resistant coating has Vickers hardness (HV) of 1,200 to 1,800, bonding force of more than 60 Mpa, and high mechanical property, wear resistance and corrosion resistance.

Description

technical field [0001] The invention relates to a wear-resistant coating and a preparation process thereof, in particular to a composite metal carbide wear-resistant coating and a preparation process thereof. Background technique [0002] With the optimization and upgrading of the industrial structure of the manufacturing industry, reliability and durability have become the key to mechanical equipment and parts. Many mechanical parts cause premature failure or scrap due to local wear and corrosion on the surface. In order to improve the wear resistance and corrosion resistance of the surface of mechanical parts, a large number of medium carbon steel and medium carbon alloy steel are subjected to surface hard chrome plating, electroless nickel phosphorus alloy plating, surface ion nitriding, spraying Ni60 coating and other treatments after quenching and tempering heat treatment. . However, a large amount of hexavalent chromium pollutes the environment in the production of e...

AI Technical Summary

Problems solved by technology

However, a large amount of hexavalent chromium pollutes the environment in the production of electroplating chromium, and the production of hexavalent chromium has been banned in various countries; electroless nickel-phosphorus alloy has relatively good corrosion resistance, but it cannot meet the requirements of wear resistance; ionic nitrogen Although it can improve the wear resistance of parts surface to a certain extent, its shortcomings of long process cycle and easy deformation of parts are also obvious; the sprayed Ni60 coating has a certain surface hardness, but the sprayed surface is not dense enough, and the porosity of the coating is relatively high. Big

[0003] Coating technologies such as explosive spraying, supersonic flame spraying, and plasma spraying WC-12Co, WC-17Co, and WC-17Ni developed in recent years have improved the surface hardness of parts to a certain extent, but still show that the wear resistance of the coating is not enough Well, especially a single-size WC coating or a single type of tungsten carbide coating is difficult to meet the requirements of parts that require surface abrasion resistance, certain toughness and low surface roughness, and these tungsten carbide coatings have a little porosity. High, coating adhesion is not high enough, which limits its application to a certain extent