Low cost powder metal turbine components

Abstract

Driving down processing costs on military and commercial aerospace components is an unending quest for the process metallurgist. Concurrently, the integrity of the powder metal (PM) component must be maintained or improved in these high strength, high temperature, fatigue limited components. A unique processing route, slightly subsolidus hot isostatic pressing (SSHIP) combined with press conversion operations has provided an alternative process route for PM processing of turbine disk materials. The SSHIP + press conversion process route provides the potential for new thermomechanical processing routes for turbine disks, rings and seal components. Under funding from the AFRL Metals Affordability Initiative, a modified powder metallurgy process route has been investigated to reduce the processing costs and logistics problems associated with specialized equipment for the conversion of highly alloyed superalloy forging billet. An Advanced Integrated Process Team (AIPT) consisting of General Electric Aircraft Engines, Rolls-Royce Corporation, Ladish Co., Inc. and Special Metals Corporation utilized task driven program management tools in the application of this technology for production turbine components. In this paper, the transformation from laboratory studies using production alloys to turbine disk property results will be presented. The evaluations demonstrated that the SSHIP + conventional press forging process route provides a technically feasible alternative process route for advanced turbine component hardware.