Wetting behavior of Al on the surface of SiC textured by nanosecond laser

Abstract

Recently ultrafast laser has been used to process materials to obtain functional surface. However, most of the existing research is focused on metals, and only a few studies considered ceramics. In the current work, the effects of laser texturing on the wetting behavior of Al/SiC systems is investigated by modified sessile drop method. The surface of SiC is textured by nanosecond laser with ordered square grids. Then, the wetting behaviors of Al on both raw and textured SiC are investigated. The processed SiC surface and wetting interface are characterized by XPS, SEM, and XRD. Finally, the spreading kinetics is calculated. It is observed that laser texturing induces the melting and elimination of SiC, resulting in the generation of microsynapses and deposited carbon in grooves. The microstructure and chemical composition enhance the interfacial reaction, which results in faster spreading speed (spreading kinetics kr increases from 0.0041 to 0.011 at 1273 K) and higher wettability (final contact angle θ decreases from 78° to 42°). In addition, a considerably lower activation energy of spreading (164 kJ/mol) is obtained. The results demonstrate that laser processing is an effective method to enhance the wettability of metals on ceramics.