抄録
CAC804 copper alloy, a type of lead free copper alloy, has higher strength. The effects of cooling rate on microstructures and mechanical properties were investigated for alloy cast into a shell mold with a stepped cavity. With increasing cooling rate, the microstructure of the alloy became finer, resulting in increased hardness. The tensile strength tended to increase and the elongation decrease with increasing cooling rate. This was thought to be due to micro defects formed during the casting process. CAC804 alloy casting prepared with a cooling rate of 10K/s had Vickers hardness of 135Hv, tensile strength of 500MPa and elongation of 30%. It was found that CAC804 copper alloy is effective for manufacturing thin-walled castings.
