DEFORMATION-BEHAVIOR AND SLIP SYSTEMS OF QUENCHED BETA-CUZN SINGLE-CRYSTALS

The effect of quenching temperature and orientation on the yield stress and slip system at 290 K in quenched β-CuZn single crystals was investigated. The yield stress was remarkably dependent on quenching temperature and showed a maximum value by quenching from around the order-disorder transformation temperature (Tc) independent of orientation. A {110} slip plane which is the same as that in an annealed crystal was observed in the crystal strengthened by quenching from just above Tc in the orientation of χ ≧ +20°. but a plane which deviates from {110} to {112} plane in the twinning sense was operative with decreasing χ, where χ is the angle between the primary slip plane {110} in an annealed crystal and the maximum resolved shear stress plane (MRSSP) measured from the {110} toward {112} in the anti-twinning sense. The electron microscope observation and the orientation dependence of the yield stress and slip system in a quenched crystal deformed at 77 K suggest that the observed slip systems at 290 K are associated with the orientation dependence of critical resolved shear stress (CRSS) for {110} 〈111〉 and and {112} 〈111〉 slip systems in the quenched and the annealed crystals. © 1979.