Timetal 551 is an improved-strength version of Timetal 550 alloy that retains good forging characteristics. The alpha-beta alloy has a nominal composition of Ti-4Al-4Mo-4Sn-0.5 Si, and it is used in gas turbine engine parts. This datasheet provides information on composition, physical properties, elasticity, tensile properties, and shear strength as well as creep. It also includes information on high temperature performance as well as forming and heat treating. Filing Code: TI-138. Producer or source: Timet.