Strain hardening of a hot stretch formed Ti-6Al-4V alloy aircraft component

The strain hardening of a large titanium component for aircraft applications processed through hot stretch forming below the β transus is studied. Tensile specimens were extracted from zones of the forging characterised by different thermomechanical histories to analyse their differential hardening. Data obtained from the tensile testes were compared to hardness measurements and microstructure observations. It was found that the material experienced higher strain and strain rate with increasing the distance from the die. This resulted in a higher strain hardening of the related zones of the forging, which show a loss of ductility and an increase of the tensile properties in contrast with less stressed regions.