抄録
The paper presents experimental results for tensile creep behavior of orthogonal 3-D woven Tyranno^<TM> fiber/Si-Ti-C-O ceramic matrix composites at 1300-1450℃ in air. The composites exhibited excellent tensile properties at elevated temperature in air. For creep stresses between 60 and 140 MPa, the creep rate decreased continuously with time, with no apparent steady-state regime observed at 1300-1450℃. Under the test conditions, the microstructure of Tyranno fiber and Si-Ti-C-O matrix was unstable, resulting in weight loss and SiC grain growth. As a result, the viscosity of the fiber and matrix increased because of increase in viscosity caused a continuously decreasing creep rate, which made steady-state creep impossible under these conditions.
