Experimental crack propagation and fracture failure analysis of the titanium alloy blade subjected to high cycle fatigue

Abstract

This paper investigates the crack propagation and fracture failure of the gas turbine compressor blades on the vibrator rig. The blades used in the investigation were the newly qualified specimen from gas turbine factory, without any preliminary cracks or corrosion pits. The casting blades made of titanium alloy were entered into the transverse vibration in the resonant condition during the experiment. During the high cycle fatigue test, the growth of the crack was monitored and measured with the method of dye penetration. In the second part of work, finite element method (FEM) was utilized to calculate the stress distribution of the blade during vibration, and the first mode of transverse vibration was considered in the analysis. The maximum principal stress zone of the finite element model in the resonance condition was at the place where the crack occurred.