The present study focuses on multiple cracks that occur in uni-directionally reinforced CMC's (ceramic matrix composite) under tensile loads, with fiber oriented at an angle pi/2- ph to the load direction. These composites were observed to develop fiber-bridged matrix cracks perpendicular to the load directions, with subsequent inclined extensions along the fiber-matrix interfaces. The foregoing fracture phenomenon is investigated analytically using a combination of a displacement based finite element scheme and an eigen function expansion method which establishes both near field and far field solutions. It is observed that when the matrix crack impinges on the inclined fibers, tensile stresses arise along the interface inclined at an angle (phi> and compressive stresses along the interface inclined at an angle hi-pi. This result explains experimental observation where fractures were noted to evolve along fiber-matrix interfaces inclined at an angle phi to the direction of matrix crack. Computations were performed for SiC/CAS ceramic composite with phi=60 deg.
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