국내 최대 기계 및 로봇 연구정보

기술보고서

기술보고서 게시판 내용
타이틀	Low-Cost Production of Composite Bushings for Jet Engine Applications
저자	Robert A. Gray
Keyword	Low toxicity; Low-cost; High-temperature; Polymides; AMB-21; MDA; Composites; Carbon fiber; Diamine; Molding compound; Compression and injection molding;
URL	http://gltrs.grc.nasa.gov/reports/1998/CR-1998-208515.pdf
보고서번호	NASA CR-1998-208515
발행년도	1998
출처	NASA Glenn Research Center
ABSTRACT	The objectives of this research program were to reduce the manufacturing costs of variable stator vane bushings by 1) eliminating the expensive carbon fiber braiding operation, 2) replacing the batch mode impregnation, B-stage, and cutting operations with a continuous process, and 3) reducing the molding cycle and machining operations with injection molding to achieve near-net shapes. Braided bushings were successfully fabricated with both AMB-17XLD and AMB-TPD resin systems. The composite bushings achieved high glass transition temperature after post-cure (+300캜) and comparable weight loss to the PMR-15 bushings. AMB-17XLD bushings made with "batch-mode" molding compound (at 0.5 in. fiber length) achieved a +300 lb.-force flange break strength which was superior to the continuous braided-fiber reinforced bushing. The non-MDA resin technology developed in this contract appears attractive for bushing applications that do not exceed a 300캜 use temperature. Two thermoplastic polyimide resins were synthesized in order to generate injection molding compound powders. Excellent processing results were obtained at injection temperatures in excess of 300캜. Micro-tensile specimens were produced from each resin type and the Tg measurements (by TMA) for these samples were equivalent to AURUM? Thermal Gravimetric Analysis (TGA) conducted at 10캜/min showed that the non-MDA AMB-type polyimide thermoplastics had comparable weight loss to PMR-15 up to 500캜.