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

This paper deals with the dry sliding wear behavior of cold-sprayed Inconel 738 (IN 738) coating up to 600 degrees 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 degrees 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 degrees 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 degrees 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.