Titanium Alloys

• Pure Titanium – low density (4.5Mg/m³), High Melting point (1660 ^oC), Tensile Strength 150-500Mpa
• Alloying required to reduce cost, increase strength & control phase
• Two crystal forms – below 883oC alpha structure (HCP) and beyond beta (BCC)
• Four alloys: Alpha, Near Alpha, Alpha-Beta, Beta
• Alpha alloys- These are non-heat treatable and are generally very much 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.
• Alpha-Beta alloys are heat treatable to varying extents and most are weldable with the risk of some loss of ductility in the weld area. Strength levels are medium to high. Hot forming qualities are good but cold forming often presents difficulties. Creep strength is not usually as good as in most alpha alloys
• Beta or near beta alloys are readily heat treatable, generally weldable, and offer high strength up to intermediate temperature levels. In the solution treated condition, cold formability is generally excellent.