Wear behavior of Mg-10Y-4Gd-1.5Zn-0.4Zr alloy
(1. School of Materials Science and Engineering, Harbin University of Science and Technology, Harbin 150040, China;
2. National Engineering Research Center for Light Alloy Net Forming,
Shanghai Jiao Tong University, Shanghai 200240, China;
3. College of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin 150001, China)
2. National Engineering Research Center for Light Alloy Net Forming,
Shanghai Jiao Tong University, Shanghai 200240, China;
3. College of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin 150001, China)
Abstract: Dry sliding wear tests were performed on a Mg-10Y-4Gd-1.5Zn-0.4Zr alloy using a Ball-on-Flat type wear apparatus against an AISI 52100 type bearing steel ball counterface. The wear rates were measured within a load range of 3-25 N, a sliding speed range of 0.03-0.3 m/s and a sliding temperature range of 25-200 °C at a constant sliding distance of 400 m. The morphologies of the worn surfaces and wear debris were studied by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Comparatively, the wear properties of a hypereutectic Al-Si aluminium alloy under the same condition were measured. The results indicate that the wear rates of Mg-10Y-4Gd-1.5Zn-0.4Zr alloy are lower than that of cast+T6 AC9B aluminium alloy. The dominant mechanism of cast+T6 Mg-10Y-4Gd-1.5Zn-0.4Zr alloy is abrasion wear mixed with other wear mechanisms, which tends to be an abrasion and plastic deformation wear at high normal load such as 10-25 N, abrasion and plastic deformation wears with small participation of delamination and oxidative wears at high sliding speed such as 0.12-0.3 m/s, and an oxidative and abrasion wear at high test temperature such as 100-200 °C. The Mg12Y1Zn1 phase in Mg-10Y-4Gd-1.5Zn-0.4Zr alloy plays an important role in the wear rate.
Key words: Mg-Y-Gd-Zn-Zr alloy; sliding wear; wear rate; wear mechanism; hypereutectic Al-Si alloy