New Conceptual Lead Free Overlays Consisted of Solid Lubricant for Internal Combustion Engine Bearings

Two types of new conceptual lead free overlays are developed for automotive internal combustion(IC) engine bearings. The overlays are consisted of molybdenum disulfide(MoS₂) and polyamideimide(PAI) resin for binding. One of the overlays is suitable for diesel engines with higher unit load and the other overlay is suitable for gasoline engines with higher sliding velocity. Both overlays indicate good corrosion resistance and wear resistance comparing with conventional lead base overlay. Moreover, higher fatigue resistance is obtained in combination with high performance lead free bearing alloy. These new bearings have the potential to become alternative materials to conventional copper lead bearings with lead base overlay.