Reaction of nanocrystalline Cu-Sn alloy with Ga-In-Sn eutectic

An extended solid solution of Cu-20%wtSn with a lattice parameter of 0.3715 nm and a crystalline grain sizes D ranging from 30-7 nm was obtained by mechanical alloying. The reaction rate for the formation of CuGa2 due to the interaction of Cu-20%wtSn with a Ga-In-Sn liquid at room temperature increased significantly when D decreased to 7 nm. A mechanical alloying process was used to control the reactivity of the nanocrystalline solid solutions, used as components in the low temperature solder pastes.