Cavitation Damage During Flexural Creep of SiAlON–YAG Ceramics
نویسنده
چکیده
Cavitation damage in flexure bars crept at 1170°C was studied by a density measurement technique. The cavity density within the flexure beams could be approximated by a linear function of position from the tensile surface. A threshold stress for cavitation damage is suggested from the results of this study. Below the threshold tensile stress, cavitation ceases, whereas above the threshold, cavitation damage is in the form of wedge-shaped cracks at grain-boundary triple junctions. Cavitation is not observed in compression for the conditions used in this study. From a stress analysis of the flexure bars, a cavitation threshold of 55 MPa is estimated for this material. [
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