Abstract
Mechanical properties and sliding wear characteristics of Cu-10mass%Sn composites containing graphite or molybdenum disulfide (MoS2) produced by powder metallurgy techniques were investigated in order to develop a suitable self-lubricating and anti-wear material for use under dry sliding conditions. Graphite and MoS2 powders were coated with copper for the purpose of promoting the bonding between a copper particle and the lubricant particle during the sintering process. The hardness, microstructure, bending strength, wear and coefficient of friction of the sintered specimens were examined. It was found that the mechanical properties of the composites decreased with increase of the amount of addition of graphite or MoS2. However, the use of the copper-coated lubricant powders improved the strength. Graphite addition was very effective in reducing the wear and friction. Moreover the wear rate of the copper-coated graphite specimens was much smaller than that of the uncoated graphite specimens. By contrast, the wear rates of the MoS2 composites increased considerably with the amount of MoS2 addition. This behavior is thought to be due to the absence of MoS2 and the presence of brittle CuMo2S3 compounds in the sintered composites.
