The influence of laser power and scanning strategy on the cracking behavior of TiC reinforced high carbon steel alloy

TiC reinforced high carbon steel hard alloy is a widely used wear-resistant material in the industrial field, but cracks are prone to occur during laser cladding preparation. The influence of laser power and scanning strategy on the crack behavior of hard alloy was investigated through simulation analysis and cladding experiments in the article. Using ANSYS software and finite element method, the temperature gradient and residual stress distribution in the laser cladding layer were investigated. Scanning electron microscopy (SEM) was used to analyze the microstructure. The results showed that different laser power and scanning strategies would lead to different thermal gradient distribution, residual stress distribution, and microstructure evolution in the cladding layer. This is the main reason for the different cracking tendencies of the cladding layer. The combination of high laser power and reciprocating scanning strategy brings high heat input and low temperature gradient, which can effectively reduce the tendency of cracking. With the increase of laser power, TiC ceramic phase will melt and dissolve, and the alloy will exhibit obvious tempering microstructure characteristics, gradually forming bainite and tempering martensite structures, which further helps to reduce the tendency of crack generation