Microstructure Evolution and Lifetime Extension Mechanism of Sn-Added Fe-Based Pre-Alloy Brazing Coating in Diamond Tools

Abstract

The effect of Sn content added in pre-alloy powder on the microstructure, porosity, hardness and bending strength of hot pressing sintering of a diamond matrix was investigated. The results show that with the increase of Sn content in the pre-alloy powder, a reduction in grain size and porosity as well as an increase in hardness is observed. As a result of the reduction in porosity, the flexural strength increases with the increase in the Sn content in the pre-alloy powder. However, with the increase of Sn content, the bending strength decreases owing to the formation of Cu5.6Sn in the matrix. The properties of the diamond matrix are improved, and the lifetime of the diamond matrix is prolonged when the Sn content is 4 wt.%.