A. P. Woodfield, E. A. Ott, GE Transportation, Cincinnati, OH

Summary:

GEAE has been actively participating in the recent DARPA-led Titanium Initiative, assessing different processes that have the potential to produce Ti alloy particulate or sponge that is clean enough to be directly consolidated to form ‘meltless’ Ti alloy materials. Recent reports suggest that there are many novel reduction processes that are currently under consideration [1]. There are several potential advantages with the approach to direct alloy manufacture omitting the melting step, including the production of homogeneous alloys that cannot be produced via traditional melting methods, and the generation of materials with substantially refined microstructures.

The prospect of forming new, or novel alloys, and alloys with substantial microstructural refinement is particularly intriguing, as it offers the potential for significant improvement in Ti alloy properties. However, the ability of the numerous reduction processes to successfully produce novel alloys and alloys with refined microstructures differ, as the reduction temperatures and times vary greatly. The results from some recent experiments will be presented demonstrating the feasibility of producing meltless Ti-64 with a substantially refined microstructure, and a novel meltless Ti alloy that could not be produced by melting. The reported results will include microstructural characterization, and some high level screening mechanical properties.

[1] E.H.Kraft, Low-Cost Titanium Workshop, Dec. 2003, Baltimore.