Abstract
Development of new low-cost methods for spray forming Titanium alloys is critical for many industries. Direct fabrication technologies would have an impact on many industries because of the potential for quick manufacture of parts or additive features with minimal waste. For example, in the aerospace industry the buy to fly ratios can vary from 1.5:1 for turbine blades to over 22:1 for structural members. The buy to fly ratio is the mass of material that is require to machine a part compared to the mass of material in the finished part. For compressor and ring sections, the ratio is approximately 12:1. For this family of parts, an analysis by Pratt & Whitney indicated that the buy to fly ratio could be reduced by 41% to 7:1 if cold spray could be implemented to deposit isogrids, structural ribbing, bosses, and flanges reducing the material, machining, and post processing required for the final part. This paper summarizes the results of experiments conducted in Phase I of a National Science Foundation grant to spray form Titanium alloy using the cold spray process. This paper further describes the studies performed to date in Phase II and the techniques used to decrease the porosity of the as-sprayed coating from 18% to between 2% and 5% and the post processing methods employed to further consolidate the coating and restore the as-sprayed material to near wrought properties.
