HIGH-TEMPERATURE DRY SLIDING WEAR BEHAVIOR OF COLD-SPRAYED INCONEL 738 COATING

Abstract

This paper deals with the dry sliding wear behavior of cold-sprayed Inconel 738 (IN 738) coating up to 600∘ C. The coating was deposited by a high-pressure cold spray system using helium as the propellant on T11 low-carbon steel substrate. The dry sliding wear behavior of uncoated specimens is compared with IN 738 coating using pin-on-disk tribometer (ASTM G99). SEM, EDX, and XRD analyses provide better insights on the worn surface morphology, changes in oxide scales, and phase transformation. At 400∘C, the tribo-layer developed at the interface contains NiO, which is a lubricious oxide, which reduces the wear rate of the coating. With further increase in temperature up to 600∘C, there is a formation of a protective layer, which results in the enhancement of high-temperature dry sliding wear resistance of the coating. At 600∘C, sliding wear resistance offered by the coating is approximately four times higher than T11 low-carbon steel. Therefore, the developed cold-sprayed IN 738 has high potential for usage at elevated-temperature dry sliding applications.