The Improvement of the Wear Resistance of T15 Laser Clad Coating by the Uniformity of Microstructure

Abstract

The uniformity of microstructure and wear properties exist in the T15 coating for the laser cladding on 42CrMo steel. It can be improved by a post-heat treatment process. Temperature ranges from 1100 to 1240 °C were applied on the cladding layer to investigate the effect of the heat treatment on the wear resistance and hardness gradient. The post-heat treatment can efficiently improve the inhomogeneity of microstructure. The lower wear rate is obtained after the quenching process at 1100 °C, and the wear rate is increased though the tempering process. The carbides at the grain boundary are decomposed and integrated into the matrix during the high temperature quenching process. The carbides are precipitated and dispersed in the grain during the tempering process. The content of martensite and alloy carbide is significantly increased through the heat treatment process. The microhardness of the cladding layer is 910 HV after quenching and 750 HV after tempering. The wear mechanism of the cladding layer is mainly abrasive wear and fatigue wear. The crack and falling off from cladding layers are significantly reduced for the quenching–tempering process.

Influence of Post-Heat Treatment on the Characteristics of FeCrBMnSi Coating on Stainless Steel 304 Substrate Prepared by Twin Wire Arc Spray (TWAS) Method at Various Stand-off Distance

“…Decreasing the hardness of the coating will make the wear resistance of the coating material tend to be low [35], [67]- [73]. A increase in stand-off distance results in a decrease in hardness value which will make the mass loss and wear rate of the specimen tend to be high [24], [28].…”

Surface Modification of 42CrMo Steels: A Review from Wear and Corrosion Resistance

“…Similarly, wear resistance can be further improved by heat treatment of laser-fused cladding. By heat treating the T15 LC coatings on the surface of 42CrMo steel, Zhang et al [63] showed that the inhomogeneity of this coating could be effectively improved. This treatment resulted in a notable increase in the content of martensite and alloy carbide, consequently enhancing the resistance to abrasion.…”