Liquid metal dealloying of titanium-tantalum (Ti-Ta) alloy to fabricate ultrafine Ta ligament structures: A comparative study in molten copper (Cu) and Cu-based alloys

Abstract We report dealloying of Ti60Ta40 in molten copper, eutectic Cu28Ag72 alloy and Cu20Ag40Bi40 alloy for the fabrication of ultrafine Ta ligament structures across a 1-mm thick section. When dealloyed in molten Cu and Cu20Ag40Bi40, the melt temperature dictated the length scale of Ta ligaments, which decreased exponentially with decreasing temperature. Conversely, dealloying in molten eutectic Cu28Ag72 led to complex Ta ligament structures due to Ag enhanced surface diffusivity of Ta by Ag. Ultrafine (