Titanium Hardening

Titanium hardening is not a common welding process. If you hear that, it's usually about alloying titanium during welding to form carbides. That makes the structure harder and more wear-resistant, but also more brittle. If you do it wrong, you get stresses and cracks in the material. So make sure you control the heat input and don't cool the part too quickly, or the structure will crack open.