Self accommodating shear strain
Many experiments have been performed in order to observe and measure this dilatation.
They all concluded that this parameter do not differ substantially from unity: “It appears that the refined and indeed elegant generalization of the original theory, wherein a single shear is replaced by two, leads to improved but not completely satisfactory prediction for the case.
It should be noted that for twin-related variants pairs, a linear combination satisfy the volume conservation: .The continuous analytical expression associated to this distortion is given in reference ref. The FCC-BCC distortion D of equation (2) is not an invariant plane strain, but an invariant line strain, as only the direction is undistorted during the transformation.By computing the distortion matrix in the reciprocal lattice D* = D plane is explicitly imposed to be untilted by the Kurdjumov-Sachs orientation relationship (1).The absolute basis for expressing the transformation matrix is therefore equal to the basis relative to the first variant .By convention, if the basis in which the vectors and matrix are expressed is different from the absolute basis .
Search for self accommodating shear strain:
Based on these characteristics, various models have been developed in order to describe and understand the transformation.