Sliding wear behaviour of Ni-5 %Al coating deposited by detonation spray on IN718

Abstract

Ni-5 %Al metallic coating was deposited on Nickel-based superalloy (IN718) specimens using the detonation spray coating (DSC) method. Detonation spraying yielded coating with extreme chemical bond strength, hardness, and less porosity. The microstructure, microhardness, and room temperature pin-on-disc sliding wear behavior of the Ni-5 %Al coating and the as-received IN718 superalloy were evaluated. Sliding wear tests were done at room temperature (25 °C), under different loading conditions (6 N and 10 N), using an alumina (Al<inf>2</inf>O<inf>3</inf>) ball-on-disk tribometer and friction coefficients were measured. The study of worn surfaces conducted by SEM indicated that both Ni-5 %Al coating and the substrate suffered significant abrasive wear with occasional adhesion and spalling of the coating. The 3D topography of the wear track was examined by a 3D non-contact profilometer, which enabled the quantification of the wear. The friction coefficient values of the tests and the wear in terms of mass loss were in good correlation. © 2022