Fretting Wear Performance of Inconel 625

The purpose of this work is to study the effect of three key parameters, load, amplitude and frequency, on fretting wear performance of Ni-based Inconel 625 alloy at ambient temperature and pressure. Friction coefficient and wear volume are calculated and analyzed. The cross and 3D surface profiles of wear scar are observed. The chemical composition and phase composition of the worn surface are analyzed by Energy Dispersive Spectrometer and X-ray Photoelectron Spectroscopy. The fretting wear damage mechanisms are discussed. The results indicate that of the three parameters, frequency has the maximum effect on friction coefficient. The average friction coefficient slightly decreases as load and amplitude increase while it significantly increases as frequency increases. The wear rates markedly increases as amplitude and load increase. Based on the observation of the worn surface different regions of the wear scar show different wear mechanisms, i.e. adhesion and peeling for the center wear area, typical particle attrition for the sliding area, while deformation of the matrix and adhesion of wear debris for the edge of the wear scar. The oxide layer are composed of iron oxides Fe₂O₃ and Fe₃O₄ or FeO, and a small amount of chromium and nickel oxides NiO, Ni₂O₃, Cr₂O₃ and nickel.