Cu-25Zn-6Al-3Fe and Cu-25Zn-6Al-3Fe-4Mn alloy samples were prepared by medium frequency induction furnace smelting and graphite mould casting.The hardness and tribological properties of the two alloys were tested

respectively

and structure of the alloys was characterized by OM

XRD

SEM and EDS.The results reveal that both two kinds of alloy are composed of the CuZn matrix and the second phase.The addition of manganese does’ t change the type of the main strengthening phase and the self-lubricating phase of the alloy

and component testing confirms that the second phase of the two alloys belongs to iron-enrichment phase.The manganese element in the Cu-25Zn-6Al-3Fe-4Mn alloy exists in the matrix and iron-rich phase in form of solute atoms and has the highest concentration in the iron-enrichment phase.The addition of manganese can change the morphology of the second phase particles

and refine the size of the second phase

increasing the dispersion of the particles and improving the hardness of the matrix and the second phase by solid solution strengthening.As a result

the hardness of Cu-25Zn-6Al-3Fe-4Mn alloy reaches 251（HV）

and the friction coefficient and the wear rate reach 0.319 and 5 mg

respectively

and the tribological properties are superior to those of the Cu-25Zn-6Al-3Fe.