TENSILE AND WEAR PROPERTIES OF EUTECTIC Al-Si-Mg-Ce ALLOY

Abstract

The effect of cerium addition on the microstructures and mechanical properties of the eutectic Al-Si-Mg alloys were investigated. Wear tests were conducted against a hardened carbon steel (Fe-2.3%Cr-0.9%C) using a pin-on-disc configuration with fixed sliding speed of 1 ms-1 and load of 30 N at room temperature (25oC). Both worn surfaces and collected debris were characterized by scanning electron microscope (SEM) equipped with energy dispersive X-ray spectrometer (EDX). The result shows that the addition of 1 - 3 wt% cerium resulted in the formation of rod-like intermetallic phases Al-Ce. The tensile strength of the as-cast alloy increases with the increase of Ce content, then fall down and reached a maximum value of 120 MPa when Ce content was 2 wt.%. The wear resistance of Al-12Si-4Mg alloy improved significantly with the addition of cerium up to 2 wt%. However, cerium addition of more than 2 wt% to the alloy leads to insignificant improvement in wear resistance of the as-cast alloys.