Rigid body translation in the (211) twin of the B.C.C. structure

The {110}and {321}composition planes are analysed by electron microscopy in a {211}twin in the b.c.c. vanadium. Fringe systems of the α‐type in the boundary planes reveal the presence of a rigid body translation between both elements of the twin. For the {321}planes the displacement vector is close to 1/36 <144>or close to 1/36 <522>, whilst for the {110}twin boundary a displacement vector close to 1/36 <243>is proposed. These calculated vectors are in good agreement with the observations. A curved boundary presenting α‐fringe with varying contrast is also analysed and a translation vector varying with the fault orientation is proposed.