Titanium alloy forgings are used for various parts of airframe structures and engines.In the case of the Boeing 787, for example, titanium alloy accounts for approximately 15% of structural members, more than doubling the amount used for conventional aircraft.
A titanium alloy commonly used for airframe structure parts is Ti-6Al-4V,which accounts for 80 to 90% of the titanium alloys generally used for aircraft. Ti-64 is the most widely used α-βalloy, having well balanced characteristics with an abundance of data and application history.
In aircraft engines, titanium alloys find many applications for fans and compressor parts used at temperatures of 590℃ or lower.Ti-64 alloy is used for fan disks and low-pressure compressor isks.For mid-pressure compressor disks, Ti-6Al-2Sn-4Zr-6Mo (Ti-6246) alloy and Ti-5Al-2Sn-2Zr-4Cr-4Mo (Ti-17) alloy,both near-βtype, solutioned and aged,are used.For high-pressure compressor disks, which are exposed to higher temperatures,forgings made of heat-resistant titanium alloys are used.
