Question

How does the addition of am Alpha stabilizer strengthen titanium?

Answer 1

The binary phase diagram formed by addition of an alpha stabiliser (such as aluminium, oxygen, nitrogen or carbon) to titanium.Oxygen is added to pure titanium to produce a range of grades having increasing strength as the oxygen level is raised. Aluminium is the only other alpha stabiliser used commercially and is a major constituent of most commercial alloys. It is a very effective alpha-strengthening element at ambient and elevated temperatures up to about 550°C. The low density of aluminium is an additional advantageous feature but the amount that can be added is limited because of the formation of a brittle titanium-aluminium compound at aluminium contents exceeding about 8% by weight.

Alpha alloys- These are non-heat treatable and are generally very weldable. They have low to medium strength, good notch toughness, reasonably good ductility and have excellent properties at cryogenic temperatures. The more highly alpha or near alpha alloys offer high temperature creep strength and oxidation resistance.

882 100% Ti Alloy content Figure 1. Effect of alpha-stabilizing elements on titanium