Alloy design of Zn–Al–Cu solder for ultra high temperatures

Zn-based solders were developed for ultra high temperature applications with the alloying elements: (4–6) wt.% Al and (1–5) wt.% Cu. The solder was designed to have a liquidus temperature between 655 and 675 K. The Al content improved the spreadability and electrical resistivity, but the Cu content had insignificant influence on the characteristics. The alloying contents increased hardness and tensile strength with the α–η eutectic/eutectoid. The multiple regression analysis on the measured characteristics was conducted for the alloy design of the Zn–Al–Cu solder.