The microstructure and wear behaviour of sintered astaloy 85Mo

Abstract

Powder metallurgy enables cost effective production of powder metallurgy (PM) parts with complex geometries in automotive applications. PM materials are also extensively used for the production of components subjected to working conditions giving rise to sliding, rolling or abrasive wear, such as gears or cams. In this experimental study, Fe based pre-alloyed Astaloy 85Mo powder was used in the production of camshaft spur gear. The gas carburizing is carried out at 925°C for 3 hours. The camshaft spur gears were waited at 850°C for 1 hour to reach the required carbon concentration. Oil hardening is carried out at 82°C, soaking time is 30 min. The effect of gas carburizing on the microstructure, density, hardness and wear properties of Astaloy 85Mo+0.5% graphite was investigated. Furthermore, the microstructure characterization and worn surfaces of camshaft spur gear were examined using a high magnification optical microscope. © 2014 WIT Press.