Heres the important part
Resistance to gases
Titanium alloys perform well in many aggressive environments:
Oxygen and air
Titanium alloys are totally resistant to all forms of atmospheric corrosion regardless of pollutants present in either marine, rural or industrial locations. Titanium has excellent resistance to gaseous oxygen and air at temperatures up to 370°C (700°F). Above this temperature and below 450°C (840°F), titanium forms colored surface oxide films which thicken slowly with time. Above 650°C (1200°F) or so , titanium alloys suffer from lack of long-term oxidation resistance and will become brittle due to the increased diffusion of oxygen in the metal. In oxygen, the combustion is not spontaneous and occurs with oxygen concentration above 35% at pressures over 25 bar (350 psig) when a fresh surface is created.
Nitrogen and ammonia
Nitrogen reacts much more slowly with titanium than oxygen. However above 800°C (1400°F), excessive diffusion of the nitride may cause metal embrittlement. Titanium is not corroded by liquid anhydrous ammonia at ambient temperatures. Moist or dry ammonia gas, or ammonia water(NH4OH) solutions will not corrode titanium to their boiling-point and above.
Hydrogen
The surface oxide film on titanium acts as a highly effective barrier to hydrogen. Penetration can only occur when this protective film is disrupted mechanically or broken down chemically or ectro-chemically. The presence of moisture effectively maintains the oxide film inhibiting hydrogen absorption up to fairly high temperatures and pressures. On the other hand, pure, anhydrous hydrogen exposures should be avoided particularly as pressures and/or temperatures increase.
The few cases of hydrogen embrittlement of titanium observed in industrial service have generally been limited to situations involving high temperatures, high alkaline media; titanium coupled to active steel in hot aqueous sulphide streams; and where titanium has experienced severe prolonged cathodic charging in seawater.
Penetration Diffusion of hydrogen into titanium is very slow at temperatures below 80°C (176°F) except where high residual or applied tensile stresses exist. If the solubility limit of hydrogen in titanium is then exceeded, (100-150 ppm for commercially pure Grade 2), titanium hydride will begin to precipitate. At temperatures not exceeding 80°C (176°F), hydride will normally be restricted to the surface layers of the metal and experience in such cases indicates that this has little or no serious effect on the performance or properties of the metal. Cases of through section hydride formation, leading to embrittlement and cracking or failure under stress are very rare. Hydriding can be avoided by the proper design of equipment and control of operating conditions.