Room temperature dry and lubricant wear behaviors of Al2O3f/SiCp/Al hybrid metal matrix composites

This study investigates the room temperature sliding wear behaviors of Al2O3f and SiCp reinforced aluminum matrix hybrid composites under both the dry and lubricant conditions. The effects of fiber orientation of Al2O3f and hybrid ratio of Al2O3f volume fraction to SiCp volume fraction on the wear behaviors are discussed in details. The composite specimens with different fiber orientations and hybrid ratios were fabricated by squeeze casting method. The tests were carried out using a pin-on-disk friction and wear tester by sliding the pin specimens at a constant speed of 0.36 m/s (570 rpm) against a steel counter disk. The scanning electron microscope (SEM) images of the worn surfaces and debris were analyzed to understand the modes of wear. The results of dry sliding tests showed that the F20P0 unhybrid composites with normal (N)-orientation of fibers had better wear behaviors than those with planer-random (PR)-orientation of fibers. However, for hybrid composites, the wear behaviors were better for PR-orientation of fibers. On the contrary, the lubricant wear behaviors of F20P0 unhybrid composites with PR-orientation of fibers were superior to those with N-orientation of fibers while the hybrid composites exhibited the reverse lubricant wear behaviors.