| Abstract:
Polycrystalline Ni]Al with a columnar grained structure was grown unidirectionally by the floating zone method at a rate of 20 mm/h. Grain boundary structure was characterized by 2.: values determined from grain orientations of two adjacent grains using a coincidence lattice theory. Two types of specimens PO and NO, whose cold-rolling directions were parallel and perpendicular to the crystal growth direction, were prepared. Workability and fracture behavior of PO and NO specimens were examined focusing on the effect of the grain boundary character on fracture. PO specimens showed the better workability than NO specimens.Low angle and coincidence boundaries exhibited a strong resistance to grain boundary fracture, while random boundaries were harmful to crack initiation and propagation.
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