DOWNSELECTION AND METALLURGICAL EVALUATION OF TI 6AL-4V DIRECT-TO-METAL FABRICATION FOR AEROSPACE GRADE APPLICATIONS

摘要

For several years, direct-metal fabrication (DMF) methods have grown more sophisticated and capable in several industries. Direct manufacturing allows a fully dense metallic part to be created directly from either a Computer Aided Design (CAD) model or in some cases a laser-scanned feature. Among DMF methods, the ARCAM units were downselected to qualify for flightworthiness due to the maturity and application flexibility for Ti-6A1-4V, among other reasons. This technology has the potential to greatly reduce lead times and thereby, shorten design development at Bell Helicopter. Also, this technology can be used to perform repairs on existing parts, or even create hybrid materials. Supporting or complementary processes in industry have also begun integrating post- and pre-processing methods to address the special needs of the various DMF platforms and methods available in the maturing DMF industry. This paper identifies and down-selects current DMF technology capabilities available in North America for use in aerospace components, and presents mechanical and metallurgical test data demonstrating its capability for Ti-6A1-4V rotorcraft components. Further investigations of required testing and postprocessing are needed.