Effect of Heat Treatment on the Microstructure, Hardness and Wear Properties of Al?15Mg₂Si?3Cu with Different Contents of Zn

摘要

The effects of heat treatment (T6) on the microstructure and dry sliding wear behavior of Al?15Mg_(2)Si?3Cu particulate metal matrix composite (PMMC) with different contents of Zn have been investigated. The composite was characterized by scanning electron microscopy equipped with energy dispersive spectrometer (EDS). Dry sliding wear experiment was performed in a pin-on-disc wear tester against a DIN 100Cr6 steel disc at a speed of 220 rpm using normal load of 30N. Results show that increasing the Zn content causes a significant improvement in hardness. This is ascribed to the observed increase in matrix strength due to the formation of Al?Zn solid solution in the matrix. Zn was also found to be powerful in increasing wear resistance. The wear results showed that abrasion is the dominant wear mechanism in the composite containing 15 wt.% Zn, whilst a combination of adhesion and delamination appears to be the governing mechanism for as-cast composites.