EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES - EUROMAT 2021

Liquid aluminum (Al)/solid nickel (Ni) is a common system in casting, brazing, coating and welding processes. The properties of the final products for such processes are closely related to the wettability between the liquid and solid at high temperature. However, wettability studies on liquid Al/solid Ni systems are still limited due to the difficulty in performing wetting experiments and the complex influence of interfacial reactions on wettability. In this work, the spreading of Al on Ni was investigated under high vacuum between 750 and 950°C. It was found that the interfacial reaction was the main factor to influence spreading. The dissolved Ni into Al has insignificant effects on droplet spreading. The interfacial reaction was identified by conducting capillary suction experiments. It was found that Al3Ni and Al3Ni2 layers formed at the Al/Ni interface during isothermal holding stage. The Al3Ni2 was adjacent to Ni substrate and the Al3Ni layer was in contact with Al. The Al3Ni was further confirmed as the primary phase and the Al3Ni2 layer was produced from Al3Ni layer with more Ni diffusion into liquid Al. Due to the fact that the Al3Ni layer contacted with liquid Al during spreading, it was the phase that can affect final wettability.