A detailed study of non-basal plane faults in 18R and 2H martensites was performed using transmission electron microscopy and high-resolution transmission electron microscopy. Four types of non-basal plane faults were possible in the 18R martensite. This set reduced to Fo and Fx, after suitable atomic relaxation, and produced 6 types of imperfect dislocation; depending upon the type of basal plane fault which finished at the non-basal plane fault. The Burgers vectors of all of these dislocations were determined by analyzing the images. The displacement vectors due to atomic relaxation along the F1- and F2-type faults in the 2H structure were carefully determined from an analysis of the dislocations which formed at the intersection of the non-basal plane fault and the basal-plane stacking faults. All of the relaxations were consistent with conservation of the volume-per-atom at the non-basal plane faults. Both non-basal plane faults reduced to the same kind of fault, with different dislocations at their ends.

Imperfect Dislocations at Non-Basal Plane Defects in 18R and 2H Martensites: Transmission Electron Microscopy Studies. A.M.Condó, F.C.Lovey: Philosophical Magazine A, 1999, 79[3], 511-26