Characterization of Fretting Fatigue Crack Initiation Processes in CR ti-6Al-4V

摘要

A study was conducted to quantify fretting fatigue damage and to evaluate the residual fatigue strength of specimens subjected to a range of fretting fatigue test conditions. Flat Ti-6Al-4V specimen were tested against flat Ti-6Al-4V fretting pads with blending radii at the edges of contact. Fretting fatigue damage for two combinations of static average clamping stress and applied axial stress was investigated for two percentages of total life. Accumulated damage was characterized using full field surface roughness evaluation and scanning electron microscopy (SEM). The effect of fretting fatigue on uniaxial fatigue strength was quantified by interrupting fretting fatigue tests: and conducting uniaxial residual fatigue strength tests at R = 0. 5 at 300 Hz. Results from the residual fatigue strength tests were correlated with characterization results.