Fabrication and Tribological Properties of in situ (Al₂O₃+Al₃Zr)_p/Al-22Si Composites

Al-22Si matrix composites reinforced by Al2O3 and Al3Zr particles were fabricated from Al-22Si-Zr(CO3)2 system via melt in situ reaction technology.The phase compositions were investgated by XRD and EPMA,the tribological properties of the as-prepared composites at room temperature were investigated by dry sliding wear test,and the microstructure of the wear tracks and wear debris were observed by SEM.The wear mechanisms were discussed.The results indicated that wear resistance of the composites was much higher than that of Al-22Si alloy.With the increase of the particles volume fraction,the wear resistance of the composites increased,and the friction coefficient of the composites trended to decrease.The wear mechanism of the composites changed from adhesion and abrasive wear to abrasive wear with the increase of the particles volume fraction.