Effects of graphite addition on the mechanical property and wear resistance of 60/40 brass

Abstract

Brass 60/40 is widely used in a number of industrial applications where wear due to friction is a major concern. A significant number of failures in components such as bushings, gears, bearings and machine parts are due to wear. This study investigates the effects of Graphite nano-particulate on the mechanical properties and wear rate of 60/40 Brass produced by sand casting with varying graphite reinforcement addition ranging from 0.4 - 2.0 wt. %. The produced castings were characterized using XRD, SEM and TEM. The XRD revealed the formation of new phases such as Cu5Zn8 and CuZn2 and the presence of free carbon within the microstructure. The wear rate of the composite specimens was evaluated using a pin-on-disc wear testing machine under dry conditions at room temperature. Taguchi’s technique and analysis of variance method were used to study the influence of applied load, sliding speed, time and weight % composition on the wear rate. The results revealed that nano-particulate graphite-reinforced brass composite containing 2.0 wt. % graphite has the best wear resistance and applied load is the dominating factor on wear rate.