Method for preparing ultra-fine grain titanium and titanium-alloy articles and articles prepared thereby

Abstract

A method for preparing ultra-fine grain titanium or titanium-alloy articles used for adjoining or assembling of detail components. Coarse-grained titanium or titanium-alloy materials typically are heated and forced under constant pressure through a friction stir processing tooling device containing a stirring chamber and a stirring rod. As the material is passed through the stirring chamber, the stirring rod solutionizes the titanium or titanium-alloy material and stirs the material to obtain a homogeneous or uniform material condition. As the processed material exits the stirring chamber of the friction stir process tooling device, it reconsolidates as an extremely homogeneous structure possessing ultra-fine grain structure. Titanium or titanium-alloy materials having been processed to achieve such ultra-fine grain material structure may then be manufactured into aerospace structural articles or components such as fasteners or articles that do not require a subsequent thermal or heat-treatment steps. The resulting fasteners, articles or components have improved material performance characteristics associated with this ultra-fine grain material structure.

Dependencies are inferred from the claim text.