On distinguishing between intrinsic and extrinsic faults in field-ion micrographs

Abstract

A simple inspection serves to distinguish between intrinsic and extrinsic faults in field-ion micrographs from f.c.c. and h.c.p. metals. The extrinsic fault gives rise to a double discontinuity in planes due to the insertion of an extra layer which is incorrectly stacked with respect to layers on both sides of the fault. The instrinsic fault gives rise to a single discontinuity. It is also shown that the distinction between the two varieties of intrinsic faults in the case of h.c.p. metals requires more detailed analysis of micrographs.