Comparison of Grinding and Wire EDM Concerning Fatigue Strength and Surface Integrity of Machined Ti6Al4V Components

Titanium alloys such as Ti6Al4 V are often employed in turbine industry components due to their outstanding mechanical properties. These properties make it hard to machine with conventional processes like broaching, milling or grinding. An alternative represents WEDM. Within this paper a comparison between grinding and WEDM of Ti6Al4 V concerning surface integrity aspects proved by bending fatigue life is set up. Due to visual inspections and surface roughness measurements a higher fatigue life of the ground specimen is assumed. In contrast the EDMed specimen show higher fatigue strength. Further surface integrity aspects have been conducted to analyse the fatigue result. Summarized, the better correlation between visual part quality, influenced rim zone and fatigue strength, shows a user-friendly quality check of EDMed parts. Furthermore, this paper shows that WEDM is an alternative to conventional processes for machining titanium alloys.