Reactive wetting of molten Al on different oriented α-Al_2O_3 single crystals at high temperatures

摘要

The reactive wetting of molten Al on three different oriented α-Al_2O_3 single crystals, R(0112), A(1120) and C(0001), was investigated by an improved sessile drop method at temperatures between 1350 and 1500 ℃ in a reduced Ar-3%H_2 atmosphere. The wettability is in the order of R > A > C. The spreading is reaction-limited and the rate is dominated by the change in the solid-liquid interfacial free energy per unit time.