Development and Dry Sliding Wear Map for Al 7075/Al2O3 Particulate Composites

Abstract

Particulate composite was developed with Al 7075 as matrix and Alumina (Al2O3) as reinforcement. Dry sliding wear map for Al7075/Al2O3 particulate was developed for studying dry sliding wear rate and wear mechanisms. The wear rate and coefficient of friction depends on load and speed in pin on disc wear testing machine. Transition from ultra-mild wear to mild wear and mild wear to severe wear depends on tribolayer, speed, and load. Pin on Disc wear test are carried out at load of 1kg to 14 kg and speed of 200 rpm to 1400 rpm. The wear rate and wear coefficient are evaluated for all the load and speed used in the test. Wear maps are constructed for 5%, 10%, 15% and 20% volume fraction reinforced composite. Wear rate, wear track morphology, wear debris and noise during wear test are considered for the identification of wear mechanism. From the developed wear map it is concluded that four wear regions for composite and three wear regions for unreinforced alloy exists. The transition load and speed for various wear mechanisms are determined from the developed wear map. Particulate composite subjected to dry sliding wear increase in volume fraction, decrease in speed and load delays the transition of wear mechanism. Seizure occurs at high load and high speed with large deposits of softer material. Wear map for the composite with higher volume fraction indicates lower wear rate and wider mild wear region