Effect of Ti element on the microstructure and properties of high chromium surfacing layer

Abstract

The self-made high chromium content flux-cored wire was used to surfacing low carbon steel under self-protection. The effect of Ti contents on the microstructure, hardness and wear resistance of surfacing layer was investigated. The results showed that the surfacing layer was mainly composed of martensite, [Formula: see text] carbide and residual austenite. As Ti content in surfacing layer increased, the shape of carbides in surfacing layer varied from lath to granular and the amount of carbides was gradually increased. The hardness of the surfacing layer was slightly increased while the wear resistance was significantly enhanced. The improved wear property could be ascribed to the increasing Ti content and the corresponding increasing amount of Ti (C, N). Ti (C, N) takes the role of heterogenous nucleation particles in the surfacing layer and promotes the formation of fine-grained hard phase (e.g., [Formula: see text] carbide). With the increase of the density of fine-grained hard phase in the surfacing layer, the resistance of cutting motion during abrasive wear test also increased, resulting in a decreased wear loss and significantly enhanced wear performance.