Effect of tungsten on the mechanical properties of Ti−9Al−3Zr alloys

1. Titanium alloys with 9% Al and 3% Zr and varying amounts of tungsten (0–10%) undergo brittle fracture in the forged condition (without heat treatment) at 20°. 2. After annealing at 900° for 1 h and stepped annealing at 900° for 20 h+800° for 100 h+600° for 100 h the ductility of the alloys at 20° does not increase, but at 600° the alloys become ductile. 3. In the range of the highest solubility of tungsten in α titanium (∼0.7% W) a slight peak of hardness and ultimate tensile strength, and lowest ductility, is visible on the curves at 600°. With further increase of the tungsten content the hardness and ultimate strength increase monotonically, almost linearly, and the ductility decreases.