The AMS 4909 specification covers 5Al-2.5Sn titanium alloy in the form of sheet, strip, and plate.

5Al-2.5Sn is an alloy made up of 5% aluminum and 2.5% tin. It is a high-strength, corrosion-resistant alloy that is commonly used in the aerospace and defense industries. Grade 6 Ti-5Al-2.5Sn alloy has high service temperature of 480°C (896°F), medium strength, and excellent weldability and fabricability. This alloy has good oxidation resistance and microstructure stability; however it is not heat-treatable.