Interfacial characterization with wettability, microstructure and interfacial thermodynamics for Ti–Al/VN system

Abstract

Interfacial characterization, which includes wettability, interfacial microstructure and interfacial thermodynamics between VN substrate and Ti–Al molten alloy with different Al concentrations, was studied by the sessile drop method at 1758 K. The wettability between molten Ti–Al alloy and VN depends on alloy composition. The initial apparent contact angle increases from 95 to 120° with increasing Al content from 40 to 80 wt.% in the Ti–Al alloys. The Ti–Al/VN system is a typical dissolution system. The effect of dissolution on the apparent contact angle is reflected in the initial stage and progresses synchronously with movement of the triple-phase line. The wettability of Ti–Al/VN system shows no remarkable improvement with the dissolution of V. AlN and TiN should be formed as the interfacial reaction products during dissolution reaction of VN substrate.