Development of Next-Generation Lead-Free Free-Cutting α + β Brass

Demand for lead-free, free-cutting brass is increasing in response to lead regulations Europe. The authors of this paper have attempted develop a lead-free with an α + β two-phase microstructure, which different from existing C6932 alloy. As result basic investigations, it was found that the addition Si β-brass dramatically reduces cutting resistance due effect appears be reduction stacking defect fault energy, and if phosphorus compounds are dispersed such β-brass, make stress concentration sources improving chip fragmentation during cutting. Based on these findings, we succeeded developing new (62.5Cu–1Si–0.07P–Zn). developed alloy contains about 55% alpha phase has excellent machinability 1.3 times higher strength than C3604.