Titanium alloy is one of the important structural materials for aircraft fuselage and engine. As a body material with good weight-reducing effect, the use of titanium alloy in the commercial and military aircraft field has been steadily increasing with the upgrading of its products in the past 50 years. The use of titanium alloy on military aircraft has reached 30%~40%. The United States took the lead in successfully applying the damage safety design concept and the damage tolerance design criterion to advanced fighter aircraft. The F-22 fighter aircraft used a large number of damage-tolerant titanium alloys and large-scale integral components to meet the design requirements of high weight loss and long life. The use of titanium alloy on civil aircraft can also account for about 10% to 15%, of which the Boeing 787 body titanium alloy dosage is 15%, which is the highest record for the use of titanium alloy for civil passenger aircraft, Boeing 787 material.
In the aerospace industry, titanium alloys are used in high-pressure compressors of aerospace engines due to their high temperature resistance and high specific strength, which greatly increases the thrust-to-weight ratio. The amount of titanium used in American fighters rose from 2% in the 1970s to 41% in the 2000s (American F22 fighters); the heavy-duty bomber B1-B used a single-machine titanium of about 90 tons; the SR-71 high-altitude high-speed reconnaissance aircraft, titanium accounted for aircraft 93% of the body weight, known as the “all titanium” aircraft.
The manufacture of advanced aerospace equipment has a strong impetus to the development of new materials and welding technology. When solving the key problems of aerospace manufacturing technology, the advantages of new materials (especially titanium alloys) and welding are becoming more and more obvious, such as reducing the structural weight. Welding techniques such as improved structural performance have evolved from the original auxiliary manufacturing process to a key technology in aircraft manufacturing.