Wear Characteristics of Plasma Sprayed Nickel–Aluminum Composite Coatings

Abstract

In the present investigation plasma spray intermetallic coating of nickel–aluminide was deposited on mild steel substrates. The response of plasma sprayed nickel–aluminide coatings to the impingement of solid particles has been presented in this study. Nickel pre-mixed with alumina powder is deposited on mild steel substances by atmospheric plasma spraying at various operating power level. The coatings are subjected to erosion wear test. Dry silica sand of average particle size 400 mm is used as the erodent. The erosion rate is calculated on the basis of coating mass loss. The erosion studies are made at different velocities and impingement angles. It is observed that, the erosion wear is strongly influenced by the angle of impact. The test is conducted at room temperature, i.e., at 278C and 60% RH. Coatings deposited at different power levels are found to exhibit different wear rates under similar test conditions. Microstructure of the coating is analyzed with SEM.