Coating method for coating composite ceramic coating layers on surfaces of refractory metal parts

Abstract

The invention discloses a coating method for coating composite ceramic coating layers on the surfaces of refractory metal parts. Firstly, the surfaces of the refractory metal parts are modified; then,a thickening agent and a dispersing agent are added in organic solvent, and composite ceramic coating layer powder is added for ball milling to prepare suspension pulp; the solid content of compositeceramic coating layer powder in the suspension pulp is controlled within 40-65%; the viscosity of the suspension pulp is 10-30 mm2/s; then, the suspension pulp is uniformly sprayed on the modified surfaces of the refractory metal parts to obtain coating layer blanks; and finally, the coating layer blanks are sintered to form the composite ceramic coating layers on the surfaces of the refractory metal parts. The coating method improves the bonding performances between the composite ceramic coating layers and refractory metal, improves the uniform coating property of the composite ceramic coating layers, and realizes uniform coating of the composite ceramic coating layers on the surfaces of the refractory metal parts with large sizes, multiple dimensions and complicated shapes.

Description

technical field [0001] The invention belongs to the technical field of coatings, in particular to a coating method for coating a composite ceramic coating on the surface of a refractory metal piece. Background technique [0002] Refractory metals have a series of excellent properties such as high melting point, good mechanical properties and electrical properties, good thermal conductivity and low thermal expansion coefficient. They are very important in many industries. However, some specific properties of refractory metals are poor. , restricting its further application. In order to meet the requirements of the application field, it is necessary to prepare ceramic coatings with different functions on the surface of refractory metal parts to improve the properties of refractory metals such as oxidation resistance, ablation resistance, erosion resistance, corrosion resistance and wear resistance, so as to make them To meet the needs of the corresponding application fields a...

AI Technical Summary

Problems solved by technology

[0003] The adhesion of ceramic coatings to refractory metals is poor, and it is difficult for directly coated ceramic coatings to adhere to the surface of refractory metals, resulting in peeling and cracking of ceramic coatings during coating and sintering, especially in large areas 1. When preparing ceramic coatings on the surface of refractory metal parts with complex shapes, due to the mismatch between the particle size of the ceramic coating powder, the solid content concentration of the slurry, the viscosity of the slurry and the adhesion of the refractory metal substrate coated with a large area, the material The slurry cannot achieve uniform coating on large-sized refractory metal substrates, and at the same time, the coated coating is prone to peeling and cracking during post-sintering, thus making the surface coating of large-sized, multi-dimensional, and complex-shaped refractory metal parts The layer is difficult to prepare, and the quality and reliability of the coating cannot be guaranteed