Effect of Cu-P master alloy on the microstructure and wear behaviour of Al- 25wt. %Mg2Si Metal matrix Composite

This study was undertaken to investigate the effect of Cu-15P master alloy (1%) as a modifier on the microstructure and dry sliding wear behaviour of Al-25wt.%Mg2Si particulate metal matrix composite (PMMC). In this work, composite was characterized by scanning electron microscope equipped with energy dispersive spectrometer (EDS), and dry sliding wear experiment were performed in a pin-on-disc wear tester against a DIN 100Cr6 steel disc at a speed of 573 rpm and normal loads of 10, 30 and 50 N on the 1000m sliding distance. By addition of Cu-15P master alloy to this composite, the primary Mg2Si morphology changes from dendrite to polygon with significant decreasing in mean diameter Mg2Si particles from 200μm to 20μm. This reduction in particles size results in improvement of tensile properties and hardness values of the composite. Wear test results also show that the addition of Cu-15p master alloy reduce the wear rate of the specimens after 1000m. The examination worn surfaces showed that the wear mechanism changed from adhesion in unmodified composite to abrasion regime in modified one

کلیدواژه ها:

MMC ، Al-Mg2Si ، Cu-P ، Wear ، Microstructure