Microstructure and properties of unleaded free-cutting brass containing stibium

摘要

A new environmental friendly cutting brass containing stibium instead of lead was produced by casting and rolling.The microstructure was observed and the mechanical,dezincification and cutting properties were studied.The results show that the white particles distribute in both grains and grain boundaries,and the particles are mainly intermetallics containing stibium.The tensile strength,yield strength and elongation percentage of half-hard Sb-brass is 461.72 MPa,213.3 MPa and 15.67%,respectively.Corresponding to HPb59-1 by the size as well as appearance of the chips and the mechanism of free-cutting,the cutting property of unleaded free-cutting Sb-brass is excellent.The unleaded Sb-brass has excellent dezincification corrosion resistance,and the average depth of longitudinal section is about 295.4 μm,while the average depth of lateral section is about 214.7 μm,and it is feasible to develop a new unleaded free-cutting Sb-brass.