The Effects of Powder Additives in Matrix Powder on Wear Resistance Coatings by LPPS and LPHS

摘要

This paper reports on the high temperature wear properties of LPPS (Low Pressure Plasma Spray) and LPHS (Laser Plasma Hybrid Spray) coatings with various amounts of pre-alloyed powders mixed with the matrix powders. The layers made by LPPS and LPHS with Cr{sub}3C{sub}2-25NiCr matrix powder by itself have lower friction coefficients and lower wear at room temperature than at a temperature of 700°C. But, the wear properties of the Fe-60Mo mixed powder coatings were better than those of the unmixed powder coatings at high temperature. The Vickers hardness of the layers to be made by LPHS were higher up to 100 times higher than those of LPPS layers in case of a Ni self fluxing powder. The mixed powders could be sprayed on the piston rings of a diesel engine by LPPS and LPHS to improve the engine efficiency at high temperatures over 500°C.