Observations of dislocations in high angle boundaries in tungsten

Abstract

Field ion microscope observations of low angle twist boundaries in tungsten have enabled particular features in the micrographs to be identified with dislocations which constitute the boundary and are largely screw in character. Comparison with micrographs of high angle tilt boundaries in the same material shows that isolated dislocations of the same type are frequently present in such boundaries also. The direction of the dislocation line is very nearly [011] with an associated shear vector component of ( a 2 ) [011].