LAUSR

In a previous work, M2 high‐speed steel consisting of Ta on #45 steel was prepared by a laser metal direct forming process. After the appropriate proportion of Ta powder is added, obvious grain refinement occurs, and the amount of retained austenite decreases. Furthermore, the microhardness, impact toughness, and wear resistance increase. On the basis of this work, the microstructure and mechanical properties of the samples are further studied after tempering at different temperatures. The phase, microstructure, hardness, and wear resistance of the two kinds of steels are characterized by X‐ray diffraction, scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, and hardness and wear tests. The results show that compared with the deposition state, the microstructure of the samples after heat treatment shows grain refinement and carbide aggregation. In addition, the hardness and impact toughness of the samples increase to different degrees after tempering at an appropriate temperature. However, after tempering, the mesh structure of the grain boundaries is destroyed, and the anchoring effect of the carbides weakens; thus, the wear rate of the samples increases to a certain extent.