Development of New PM Iron-Based Materials for Self-Lubricating Bearings

Abstract

Using PM technologies, new antifriction materials based on iron powder with different addition elements were developed in order to obtain self-lubricated bearings with improved tribological features. The elemental powder mixtures were blended for 2 hours in a 3D homogenization device, were compacted at a pressure of 500 MPa, and then sintered in dry hydrogen atmosphere at different temperatures for different maintaining times. The effect of technological parameters on physical properties (density and dimensional changes) was presented in this study. The mechanical and tribological properties (tensile strength, hardness, impact energy, friction coefficient, and wear rate) related to addition elements were evaluated. The tribological behaviour of the selected iron-based alloys was analysed by pin on disc tests without lubrication. Also, the wear surface scars and the microstructure of the wear surfaces were investigated.