As the name indicates, Alpha-Beta alloys of Titanium contain both crystal structures. They are formed by the addition less than 6% aluminium and varying amounts of the Beta forming elements. These include vanadium, chromium and molybdenum.
These alloys have medium to low strength compared to the other Titanium grades. Unlike CP and Alpha alloys, which can only be strengthened by cold work, Alpha-Beta alloys are heat treatable. Therefore, these grades can undergo machining while the material is still ductile. Then they can be heat treated to further strengthen the material.
Alpha-Beta alloys are generally weldable. However, their weldability is dependent on the amount of Beta present. The higher the Beta elements, the lower the weldability of titanium grades. Also, the higher the Beta elements, the more brittle the welds become. High-Beta grades are very strong and rarely welded.
Alpha-Beta alloys can be welded with various filler metals. It is common to use filler metal of an equivalent grade, especially for the lower alloyed materials. Another option is one grade lower to ensure good weld strength and ductility.
