Investigations on Tribological Behavior and Wear Mechanisms of Inconel X-750 Alloy in Fretting Condition

Abstract

Fretting wear characteristics of Inconel X-750 were investigated under the dry test condition. Ball-on-flat contact configuration was subjected to the oscillatory movement of different sliding amplitudes through the different time duration and normal loading. Fretting tests were carried out on the high frequency wear test rig SRV 4 at room temperature with ~60% relative humidity. Wear evolutions and fretting damage mechanisms were analyzed in the case of partial slip (PS) and gross slip (GS) regimes in respect of displacement amplitude, normal load and time. Surface morphologies were investigated by 3D optical profiler, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). It is found that displacement amplitude and normal load had strong effect on the fretting mode and damage mechanism. Matter removal by abrasive wear was dominant under the lower loads while cracks induced by fatigue were observed for higher loads during PSR, and the wear mechanisms were transformed to the damage of debris oxidization and delamination at GSR. Fretting time dependence was critical in the higher displacement amplitudes where wear volume progressed significantly. However, test duration is less consistent in the partial slip regimes (≤ 40 µm) where the wear rate and wear scar remain unchanged over time.