Effects of Loading History and Closure of the Fatigue Characteristics of Heat Treated Ti-6Al-2Sn-4Zr-6Mo

摘要

The purpose of this study was to investigate the effects of loading history and crack closure on the fatigue threshold properties of additionally heat treated Ti-6Al-2Sn-4Zr-6Mo. The crack closure measurements taken by a clip gage, strain gage mounted on the back face (BFS), and laser interferometric displacement gage (IDG) were compared. Also, the effects of heat treatment on the fatigue behavior of Ti 6246 were discussed. Three tests were run using compact test specimens at a test frequency of 30 hz. The results from these tests indicated that additionally heat treating Ti 6246 did improve its fatigue threshold characteristics. Keywords: Crack closure, Fatigue Threshold, Thesis, Loading history, Laser interferometric displacement gage. (jes)