An Investigation of Wear Behaviors of AA7075 Al Hybrid Composites

Abstract

This study investigates the wear behavior of Al hybrid composites produced by adding 4 % Ti and different amounts of B4C (ex situ) to the AA7075 alloy produced by powder metallurgy method in order to obtain TiAl3 (in situ) reinforcement phase. Different amounts of B4C (3 %, 6 % and 9 %) were added to the 4 % Ti added AA7075 alloy. Preformed parts were sintered in controlled atmosphere (argon) heat treatment furnace at 580 °C for 4 hours and then cooled. After the sintering process, the samples were characterized with scanning electron microscopy, X-ray diffraction and density and hardness measurements. Wear tests of the samples were conducted at 1ms-1 sliding speed, under 30N load for 6 different sliding distances (500-3000 m). As a result of the study, the density of the AA7075 alloys, added 4 % Ti and different amounts of B4C, was observed to decrease by the increasing amount of reinforcement elements. Also, the highest hardness value was measured for the 9 % B4C added AA7075 alloy. Wear test results showed that the weight loss of the aluminum hybrid composites increased with the increasing sliding distance. On the other hand, it was observed that weight losses of composites decreased with increasing amount of B4C.