Abstract:The effects of melt superheat and pulsed magnetic field on the microstructure, mechanical and wear properties of the Mn₅Si₃ reinforced Cu-35Zn-3Al alloy were investigated. The results indicate that after the combined treatments, the hollow formation on the prism-shaped Mn₅Si₃ particles is inhibited, due to the enhanced solute migration in melt and promoted adsorption kinetics for crystal growth. The tensile strength and elongation of the forged alloy increase by 9.0% and 66.5%, respectively. The failure type of Mn₅Si₃ particles during tension transfers from brittle cleavage fracture to pulling out of the matrix due to the higher fracture strength with diminished stress concentration, which leads to enhanced reinforcement of matrix/particle load transfer. The wear resistance of alloy is significantly improved because of reduced delamination wear, since the severe shear fracture on the Mn₅Si₃ particles with hollows under friction induced plastic deformation is restrained, alleviating the subsurface originated crack propagation and spalling.

Key words: special brass; Mn₅Si₃ phase; pulsed magnetic field; strengthening mechanism; wear resistance