Published online by Cambridge University Press: 21 March 2011
Tensile properties of Ti-35Al-15V and Ti-30Al-10V alloys were examined. These alloys contain β phase with ordered bcc structure. The total elongation of Ti-35Al-15V alloy abruptly changes from 10% to 60% around 620 ºC. Many transformation bands were observed in β grains that were highly deformed above this temperature. The hexagonal α2-phase grains in bands and the β–phase grains in bands and matrix were in Burgers type of orientation relationship. The ductility of Ti-30Al-10V alloy was highly affected by neutron irradiation. The specimens irradiated and tested at 400 °C showed almost no ductility. The total elongation of specimens irradiated and tested at 600 °C was about 10 %, while that of unirradiated ones was larger than 60 %. Specimens irradiated at 400 °C were also tested at 600 °C and the elongation was only 6 %, showing little recovery in ductility. This embrittlement suggests phase decomposition during irradiation.