e/Alpha case

Information
has gloss	eng: In metallurgy, alpha case is the oxygen-enriched phase that occurs when titanium and its alloys are exposed to heated air or oxygen. Alpha case is brittle, and tends to create a series of microcracks which will reduce the metals performance and its fatigue properties. Alpha case can be avoided by processing in a vacuumed enviroment, but, due to its costs it is usually eliminated via machining or chemical milling.
lexicalization	eng: alpha case
instance of	(noun) a light strong grey lustrous corrosion-resistant metallic element used in strong lightweight alloys (as for airplane parts); the main sources are rutile and ilmenite Ti, atomic number 22, titanium