Influence of Pico-Laser Texturing Treatments on Wetting Morphology and Interfacial Bonding Mechanism of Ni–Co Alloy with Borosilicate Glass

Due to the shorter heating time and strongly nonisothermal nature of laser-heating, laser-induced surface texturing behavior exhibits a huge difference when compared to isothermal preoxidation. In this study, wetting behavior and interfacial bonding characteristics of borosilicate Glass on kovar alloy substrates with laser surface texturing treatment was investigated and compared with three different kovar alloy surface condition, i.e., non-preoxidized (polished surface), preoxidized and, laser surface texturing. The role of microtexture in wetting was evaluated using interfacial structures. The results showed that the wetting behavior on untextured kovar alloy was dominated by adsorption/desorption and the surface textures changed the dominant limiting factors to diffusion during the early wetting process. After laser surface texturing, the diffusion of Fe atoms was promoted at the interface. The surface energy of textured substrates increased, which was beneficial for wetting. The wetting behavior was determined by the synergistic effects of the reaction, surface energy, and thermodynamic driving force. Wettability was promoted for a groove formation induced by laser surface texturing.