It is ductile only when it is free of oxygen. The metal burns in air and is the only element that burns in nitrogen. Titanium is resistant to dilute sulfuric and hydrochloric acid, most organic acids, moistchlorine gas, and chloride solutions. All are stable. Four other unstable isotopes are known.
Natural titanium is reported to become very radioactive after bombardment with deu- terons.
The emitted radiations are mostly positrons and hard gamma rays. The metal is dimorphic. The metal combines with oxygen at red heat, and with chlorine at 5500C. Titanium is important as an alloying agent with aluminum, molybdenum, manganese, iron, and other metals. Alloys of titanium are principally used for aircraft and missiles where light-weight, strength, and ability to withstand extremes of temperature are important. Each SST jet plane is expected to consume 600,000 lbs.