NOTCHED OXIDE/OXIDE COMPOSITE AT ELEVATED TEMPERATURE
Oxide/oxide composites are being considered for use in high temperatureaerospace applications where their inherent resistance to oxidation provides forbetter long-life properties at high temperature than most other ceramic matrixcomposites (CMCs).One promising oxide/oxide CMC is NextelTM 720/A(N720/A) which uses an 8-harness satin weave (8HSW) ofNextelTM 720 fibersembedded in a porous alumina matrix. Possible aerospace applications forN720/A will likely require inserting holes into the material for mounting andcooling purposes.The notch characteristics must be understood to ensuredesigns using the material are sufficient tbr the desired application.Thisresearch effort examined the fatigue and creep-rupture characteristics of N720/Awith a 0°/90° fiber orientation and notch to width ratio (2a/w) of 0.33.Specifically,12.0 mm wide rectangular specimens with a 4.0 mm center holewere subjected to axial fatigue and creep-rupture loads in 1200℃ laboratory air.Monotonic tensile tests at 1200℃ were performed on un-notched specimens toprovide a baseline for comparison with previous research.Fracture surfaceswere examined under microscope to observe microstructure and damagemechanisms.Comparisons to previous un-notched research results at 1200℃show N720/A to be primarily insensitive to 0.33 notch ratios.
S.Mall Mark A.Sullivan
Department of Aeronautics and Astronautics,Air Force Institute of Technology,Wright-Patterson Air Force Base,OH,USA
国际会议
第二届国际非均质材料力学会议(The Second International Conference on Heterogeneous Material Mechanics)
安徽黄山
英文
933
2008-06-03（万方平台首次上网日期，不代表论文的发表时间）