EBSD Orientation Analysis of Secondary Cracks in Fatigued Ti-60 Specimens

摘要

Crystal orientations around normal and dwell fatigue secondary cracks in Ti-5. 7A1-4.0Sn-3. 5Zr-0. 4Mo-0. 4Nb-0. 4Si-l. 0Ta-0. 05C (Ti-60) alloy specimens were studied using electron back scattered diffraction (EBSD) method. Fatigue tests were done at room temperature in ambient air. Crystal orientation information obtained was useful to avoid formation of crystal orientations favorable for fatigue crack initiation during hot processing and heat treatment of Ti-60 alloy. Fatigue life difference between the two fatigue modes was assumed to be related to the different facet density on the fracture surfaces.