AEROSPACE APPLICATIONS OF TITANIUM ALLOYS

  Introduction Titanium alloys are grouped into Alpha Alloys, Beta Alloys and Alpha + Beta Alloys. At low temperature, pure titanium has HCP structure and is known as Alpha titanium and at high temperature it has BCC structure and is known as Beta titanium. Pure titanium contains some amount of impurities such as Nitrogen, Hydrogen, Oxygen and Iron. The strength of titanium increases with the amount of oxygen and Iron present.   Applications of Alpha Alloys   Apart from the use of CP Ti and Ti-3-2.5 for ducts and tubing, another major application of α-alloys is in the fuel pump impeller of the turbomachinery of liquid hydrogen fuelled rocket engines. These impellers are typically made from Ti-5-2.5 and operate at high stresses at about −250 ◦C. Applications of Near Alpha Alloys   The near-α alloys are not as strong at or near room temperature as either the α + β or β-alloys, but have superior creep resistance along with the improved strength retention which is important for high temper