COATED NEAR - alpha TITANIUM ARTICLES

摘要

Articles of titanium based materials are protected against alpha case formation such as results from exposure to air at high temperatures by coating with an iron-chromium based alloy. The coating may be deposited by ion plating, sputter plating or sputter ion plating these methods being preferred for avoidance of surface contamination. A preferred iron to chromium ratio (by weight) is 10:1 to 2.5:1. Specific coating compositions (given by weight) are: a) 12Cr-1(Mo + Zr)-0.15C-balance Fe, b) 15.5Cr-4.8Al-0.3Y-0.3Si-0.03C-balance Fe.