US Patent 11987890 Methods and apparatus to case harden titanium alloys

Methods and apparatus to case harden titanium alloys are disclosed. A disclosed example method for case hardening a substrate including titanium comprises providing the substrate to a chamber; evacuating the chamber to achieve a vacuum therein, heating the substrate, providing a process gas to the chamber to diffuse hydrogen and a case hardening addition into the substrate, and evacuating the chamber to cause at least a portion of the hydrogen to diffuse from the substrate.