Stability and Wettability of Ternary Carbide Mo2Ga2C in Molten Metals

Mo2Ga2C is a novel member of MAX phases, which is a family of ternary carbide/nitride with layered structure. The stability and wettability of Mo2Ga2C in molten metals are crucial for the application of Mo2Ga2C in the field of composite materials. In this work, the stability and wettability of Mo2Ga2C in three molten metals (Pb, Sn and Zn) were investigated. Mo2Ga2C was mixed with metal powders and annealed at different temperatures under vacuum. At 700 °C, Mo2Ga2C was not stable in any of the three molten metals. The decomposition of Mo2Ga2C was affected by the type of metal matrix as well as the reaction temperature. Mo2Ga2C decomposed at 550 °C in Pb, at 450 °C in Sn, or at 650 °C–750 °C in Zn. To characterized the wettability of these metals with Mo2Ga2C, the contact angle of molten metals with Mo2Ga2C at 650 °C were measured, which are 103° for Pb, 126° for Sn and 0° for Zn, respectively. Mo2Ga2C has good wettability with Zn and is not wetted by Pb and Sn.