A comparative tribological study of Inconel X750 under surface hardened and non-hardened conditions

Abstract

Inconel X750 is known for its excellent mechanical and corrosion properties. However, investigations on its tribological performance have not been conducted extensively. In this work, such a study has been performed in dry conditions with varying contact pressures at a constant frequency and stroke length. Additionally, the results were compared with the same alloy under surface hardened conditions. Hardening was achieved by creating surface-level plastic deformation using steel balls. The deformation induced was uniform and more twinning in the grains near the surface was observed with a 20%–40% increase in hardness. Friction and wear behavior were studied using a reciprocating tribometer with a ball on flat configuration at 2 N, 3 N, 4 N, and 5 N with a 1 mm stroke distance. The surface hardened samples showed improvement in wear resistance by 30%–45% at various loads. The competing wear mechanisms found were abrasion and adhesion, depending on the conditions. Transfer layer formation was also observed in regions where adhesion was dominant. However, the onset of adhesion for the surface hardened specimen was late compared to the as-received sample. Furthermore, the geometry of the counter surface material also influenced the wear mechanism prevalent during the tests, such that they hindered the transition from abrasion to micro-adhesion.