On the inclusions in shaped gamma/gamma-alpha eutectic composites

Inclusions observed in shaped gamma/gamma'-alpha eutectic composites were investigated. The inclusions, which were identified with AIN phase, caused the termination of some growing fibres or their deviation from the original growth direction parallel to the ingot axis. Both the fibres and matrix at the vicinity of inclusions grew in [001] growth direction parallel to the ingot axis. The unique {100}(gamma/gamma')parallel to{110}(alpha) orientation relationship was found at the fibre-matrix interfaces. The deviated fibres preserved their [001] growth direction which deviated from [001] growth direction of the matrix. The deviation of [001] growth direction for the fibre and matrix was constrained to lie in the planes of preferred {100}(gamma/gamma')parallel to{110}(alpha) orientation relationship at deviated fibre-matrix interface.