1971 年 20 巻 215 号 p. 956-961
Hereunder is presented a brief report of the tensile tests performed under hydrostatic pressure up to 2000kg/cm2 on specimens of zinc single crystals with various orientation. The load-elongation curves and the features of plastic deformation to fracture varied significantly in accordance with the crystal orientation. There was, in the specimen of zinc single crystals, as in the polycrystalline specimen, the critical environmental pressure that turned the brittle manner of the specimen into the ductile. Beyond that critical point the specimen, of which angle φ between the tensile axis and the c-axis of the crystal was nearly 45° or less, varied their deformation pattern to the slip in the basal plane from the cleavage in the same plane.
In specimens with orientation other than what has been described above, twin, non-basal slip and kink were observed in addition to the basal slip. In these specimens, since the various crystal planes contribute to these deformation process, the load-elongation curves turn out to be the complex ones. There took place abrupt change in their fracture mechanism from the cleavage type to the shear type.