Wear behavior of Cu–La 2O 3 composite with or without electrical current

Abstract

A new type Cu–La 2O 3 composite was fabricated by internal oxidation method using powder metallurgy. Sliding wear behavior of the Cu–La 2O 3 composites was studied by using a pin-on-disk wear tester under dry sliding conditions with or without electrical current, rubbing against GCr15 type bearing steel disk at a constant sliding speed of 20 m/s. The influence of varying applied load and electrical current was investigated. The worn surfaces were examined using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) to determine the wear mechanisms. The results showed the Cu–La 2O 3 composites had an electrical conductivity of 81.9% IACS (International Annealed Copper Standard, 100% IACS = 58 MS/m) and a hardness of HV105. The wear rate of the Cu–La 2O 3 composite pins increased with the increase in the electrical current at high sliding speed. The main wear mechanisms of the Cu–La 2O 3 composites were found to be adhesive wear, abrasive wear and arc erosion.