Wetting Behavior and Intermetallic Compound Formation Between the Polycrystalline Ni and Liquid Sn Interface: A Molecular Dynamics and Experimental Studies

Abstract The wetting behavior and intermetallic compounds formation at the liquid Sn/Ni solid interface were studied using molecular dynamics (MD) simulations and supported with experimental studies. MD simulations and experiments were performed at 513, 533, and 553 K to evaluate the influence of temperature on wetting dynamics and the formation of Ni–Sn intermetallic compounds. Ni dissolution into the Sn drop leads to the occurrence of a reaction zone that thickens with time and temperature. It is a mixture of intermetallic compounds and amorphous Sn-enriched alloy at 553 K, as confirmed by structural analysis and intermetallic phase distribution maps. The growth of the reaction zone leads to a decrease in both the fraction and concentration of solute in the liquid phase. Experimental wetting tests based on the sessile drop method confirm the trends in contact angle decrease and spreading behavior with increasing wetting temperatures. This study provides atomic-scale insight into the dissolution process at the liquid/solid interface and wetting phenomenon, offering valuable data for the development of lead-free solder technologies. Graphical Abstract