Characterization of the mechanical behaviour of both fusion zone and base metal of electron beam welded TA6V titanium alloy

Abstract

The fusion zone of an electron beam welded Ti-6Al-4V alloy presents a a' martensitic structure which leads to a change of mechanical properties. Starting from two manufacturing processing routes for the alloy (1) a b processing followed by the weld (which will be considered as the reference microstructures), (2) an a+b processing followed by welding and a post weld heat treatment (PWHT), the microstructure can be adjusted to avoid local difference of strength, fatigue properties and impact toughness. This results from the optimisation of the process and of the PWHT. The present work investigates the mechanical behaviour and the damage mechanism of both base metal and fusion zone in regards to the microstructure and to the heat treatment parameters.