DISLOCATION MECHANISMS OF CREEP IN NI3AL

The compressive creep deformation microstructure: of polycrystalline N i3Al has been observed by transmission electron microscopy (TEM). <110 >{111} and <110>{110} slip systems have been identified in primary cre ep. Dissociation of edge superpartial pairs perpendicular to the slip plane (both {111} and {110}) is common in crept specimens. The formati on of this superdislocation configuration is thought to limit the exte nt of primary creep deformation.