Some unusal properties of the fine structure of dislocations in Ni(sub 3)Al deformed at high temperature

摘要

In Ni(sub 3)Al polycrystals deformed at 850(degrees)C and quenched rapidly, surface defects exhibit two kinds of behaviour. On the one hand, dislocation coupling by antiphase boundary (APB) and complex stacking fault (CSF) is of normal magnitude for this alloy composition. On the other hand, separations are dramatically decreased in both cases. A method to visualize antiphase boundaries using a weakly excited superlattice reflection is introduced.