The Tribological and Mechanical Properties of PI/PAI/EP Polymer Coating under Oil Lubrication, Seawater Corrosion and Dry Sliding Wear

Abstract

To investigate the tribological performance of a copper alloy engine bearing under oil lubrication, seawater corrosion and dry sliding wear, three different PI/PAI/EP coatings consisting of 1.5 wt% Ce2O3, 2 wt% Ce2O3, 2.5 wt% Ce2O3 were designed, respectively. These designed coatings were prepared on the surface of CuPb22Sn2.5 copper alloy using a liquid spraying process. The tribological properties of these coatings under different working conditions were tested. The results show that the hardness of the coating decreases gradually with the addition of Ce2O3, and the agglomeration of Ce2O3 is the main reason for the decrease of hardness. The wear amount of the coating increases first and then decreases with the increase of Ce2O3 content under dry sliding wear. The wear mechanism is abrasive wear under the condition of seawater. The wear resistance of the coating decreases with the increase of Ce2O3 content. The wear resistance of the coating with 1.5 wt% Ce2O3 is the best under-seawater corrosion. Although Ce2O3 has corrosion resistance, the coating of 2.5 wt% Ce2O3 has the worst wear resistance under seawater conditions due to severe wear caused by agglomeration. Under oil lubrication conditions, the frictional coefficient of the coating is stable. The lubricating oil film has a good lubrication and protection effect.