Dry sliding wear behaviour of Mg-10Gd-3Y-0.4Zr alloy

摘要

In present work, the wear behaviour of a Mg-10Gd-3Y-0.4Zr alloy during dry sliding has been investi gated. The experiments were carried out using Ball-on-Flat type wear apparatus against an AISI 52100 type bearing steel ball counterface in a load range of 3-15 N, sliding speed range of 0.03-0.24 m/s, tem perature range of 298-473 K and at a constant sliding distance of 400 m. Analyses of the wear tracks, worn surfaces and wear debris of the Mg-10Gd-3Y-0.4Zr alloy were carried out using scanning electron microscope. As a comparison, the wear properties of common AC8A aluminium alloy under the same con dition also presented. The results indicated that the Mg-10Gd-3Y-0.4Zr alloy exhibited low wear rate compared with cast+T6 AC8A aluminium alloy under the same condition. The wear rate of as-cast Mg-10Gd-3Y-0.4Zr alloy was lower than that of cast+T6 Mg-10Gd-3Y-0.4Zr alloy. The Mg_(24)(Gd, Y)_5 eutectic compound of as-cast Mg-10Gd-3Y-0.4Zr alloy could resist the material flow during friction and wear, and affected its wear rate. At high sliding speed, the retained wear debris was the major constituent of producing the severely deformed layers along the sliding direction. The trapped wear debris acted as a protective layer and reduced the wear rate.