Fatigue response of selective laser melted Ti-6Al-4V bracket: an experimental study

The fatigue response of a weight optimised Selective Laser Melted (SLM) Ti-6Al-4V bracket was studied through shaker table testing until fracture. The bracket assembly was tested at its fundamental vibration mode at 84Hz, which was outside of the key excitation frequency (48Hz) of the intended aero-engine application. The study has shown that the SLM bracket has achieved its target inertial capability of '20g' and has been demonstrated to have redundancy in the load path transfer, should a strut fail during engine operation. An analysis of the initial fracture surface suggested that the crack initiation point was the surface breaking internal void acting as a stress raising feature and a point of micro-crack initiation. The results of the shaker table test suggested that the weight optimised SLM bracket has met its performance target.