Femtosecond laser surface modification coupling with surface metallurgical reaction promotes surface plasticity of SiC

To improve the machinability of silicon carbide (SiC) during machining, promoting surface plasticity is a classical strategy. In this study, it aimed to promote the surface plasticity of SiC by combining surface metallurgical reactions with femtosecond laser (fs laser) surface modification. Firstly, an Al/Ti coating was deposited on the fs laser modified surface. After heat treatment, experimental characterization revealed metallurgical reactions that produced an intermetallic compound containing Al and Ti. Nanoindentation tests showed the surface treated by fs laser and metallurgical reactions has over a 2x increase in deformation energy compared to different surface conditions. Furthermore, a scratch test demonstrated better lateral plastic flow and uniform scratch width in the treated surface, indicating improved plasticity promotion and machinability. To reveal the effect of Ti and Al during heat treatment, ab initio molecular dynamics simulations were conducted. This investigation provides a novel strategy to promote surface plasticity and improve the machinability of SiC.