Low cost, YAG and mullite fibers by continuous extrusion and pyrolysis of metal carboxylate precursors. Final report, 1 March 1997--31 August 1998
Optimal ceramic reinforced CMS`s and MMC`s are the key to the success of many Air Force programs because of the significant promise these lightweight, high strength materials offer for meeting projected performance and protection requirements for a wide variety of aerospace applications. This Phase 1 program has explored methods of producing continuous yttrium aluminum garnet (Y{sub 3}Al{sup 5}O{sub 12}) and mullite (3Al{sub 2}O{sub 3}SiO{sub 2}) fibers. In Task 1, synthesis reactors have been constructed with 12:1 and 50:1 capacities that will enable the authors to produce up to 2 kg of precursor compounds in a single reactor directly from Al(OH){sub 3} and/or SiO{sub 2}. In Task 2, fiber processing properties were optimized. They can produce 3 m/min of 30 micrometer ave. dia. Fiber and spool it. This translates to 180 m/h. They have initiated efforts to optimize the spinning process to meet the expectations of Phase 2 work to produce 10s m/h of multi-fiber tows suitable for manufacture of ceramic/ceramic composites. In Task 3, Fiber properties for hand drawn fibers produced in earlier studies showed bend strengths as 1.9 Gpa (assuming e = 280 Gpa), but tensile tests on continuously processed fibers have yet to be done. Phase 1 goals will be to refine the processing steps necessary to produce larger quantities of fibers, with better control of fiber diameters, pyrolysis treatments and finally mechanical properties. The authors also expect to extend their efforts to improve the mullite fiber system. They must learn to cure these fibers as they are being spun and then conduct pyrolysis studies.
- Research Organization:
- Advanced Modular Power Systems, Inc., Ann Arbor, MI (United States); Univ. of Michigan, Ann Arbor, MI (United States)
- OSTI ID:
- 305713
- Report Number(s):
- AD-A-356040/XAB; CNN: Contract F49620-97-C-0006; TRN: 90200224
- Resource Relation:
- Other Information: PBD: 31 Aug 1998
- Country of Publication:
- United States
- Language:
- English
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