Özet:

The aim of this study is to examine the effect of different rolling speeds on the high temperature wear behavior of light magnesium (Mg) alloys, which have high potential for use in automotive and space vehicles. It is important to understand how the Mg alloy responds in applications such as brake pads, which are subject to wear due to friction or increased temperature due to the usage environment. Microstructurally enhanced Mg alloys containing rare earth elements have been considered as a solution to this. Here, it is based on creating more stable secondary phases to high temperature conditions in the structure instead of secondary phases with poor resistance to high temperatures. For this purpose, wear tests were applied to hot rolled Mg-2.5Al-1.0Sn-0.3Mn-0.4La-1.33Gd Mg alloy at 225°C. The microstructural characterization of the sheet materials obtained at three different rolling speeds, 1.5, 4.7 and 10 m/min, was investigated by means of light optical microscope (LOM) and scanning electron microscope (SEM). Twinning and recrystallized grains were obtained depending on the rolling speed. It has been understood that the hot wear behavior changes depending on the microstructure and the formed hard secondary phases combine with the softer matrix to contribute to the wear resistance. There was a decrease in the wear rate due to the increasing rolling speed. When the wear rates of 10m/min and 1.5m/min rolling speeds are compared, it has been seen that there is more than two. It was observed that the worn surfaces, whose wear mechanisms were examined, had mechanisms such as plastic flow, adhesive and plastic deformation.