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.

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For this study with high originality, some aspects about the sintering behaviour of Titanium based alloy used for automotive components are presented. This paper presents the experimental results concerning the processing of Ti based alloy by Powder Metallurgy (PM) technology. The initial powder mixture consists in TiH2 micrometric powder particles that have been combined with some metallic powders for improving the final mechanic-chemicals and functional properties for using in the automotive industry. The classical PM route have been applied for obtaining a low-cost Ti- alloy.As a result it was compulsory to study the parameters that influence the densification process and the sintered properties, depending on the sintering temperature. The experimental test results were processed using the STATISTICA program. Therefore the influence of these sintering temperatures on the height and diameter shrinkages, density and hardness for the alloys based on Ti micrometric powders has been studied.