Sliding Wear Performance of Plasma-Sprayed Ni–20Cr Coating on AISI 309 SS Steel

Ni–20Cr (metallic powder) was coated on AISI 309 SS steel by shrouded plasma-spray process. Subsequently, the coating was characterized by XRD and SEM analyses. The XRD analysis indicated the formation of γ-Ni phase for the Ni–20Cr coating. The wear behavior of the bare, Ni–20Cr-coated AISI 309 SS steel was investigated according to ASTM standard G99-03 on a pin-on-disk wear test rig. The wear tests were carried out at normal loads of 30 and 50 N with a sliding velocity of 1 m/s. Cumulative wear rate (CWR) and coefficient of friction \( (\mu ) \) were calculated for these cases. The worn-out surfaces were then examined by SEM analysis. The as-sprayed coating exhibited typical splat morphology. It has been concluded that the plasma-sprayed Ni–20Cr coating can be useful to reduce the wear rate of AISI 309 SS steel. Moreover, coating was found to be adherent to the substrate steel during the wear tests.