Microstructure and Sintering Properties of Cu-10 % Sn Alloy Prepared by High-Energy Ball Milling

The Cu-10 % Sn alloy powder is prepared by high-energy ball milling, and then it is cold pressed and sintered into bulk material. XRD and SEM are used to analyze the microstructure and property evolutions of the Cu-10 % Sn alloy during ball milling and sintering. The results indicate that Sn and Cu atoms combine to form a metastable Cu₆Sn₅ phase in the early stage of ball milling. The Cu₆Sn₅ decomposes again with the extension of ball milling time, and the decomposed Sn will be dissolved into the Cu lattice. After being milled for 40 h, the Cu-10 % Sn alloy powders form a single supersaturated solid solution with stable structure, and it transforms from a large thick lamellar structure to a fine, uniform and smooth surfaced granular structure. The average particle size is 30 μm, the grain size is about 26 nm, and the Sn and Cu elements are highly dispersed. The bulk material made from this ball milled powders has good comprehensive properties when sintered at 750 ℃. The metallurgical bonding between the powder particles is good, the bulk sample is basically stable, the open porosity is reasonable, and the microhardness is relatively high.