THE PHENOMENOLOGICAL THEORY OF MARTENSITE CRYSTALLOGRAPHY - INTERRELATIONSHIPS

The phenomenological theory of martensite crystallography is based on the observation that the habit plane is an invariant plane in which al l lines in it are neither distorted nor rotated by the displacement ve ctor of the invariant plane strain. The structural change is effected by a Bain deformation which follows intuitively from the orientation r elationship and through which atomic interchanges do not occur. A latt ice invariant deformation is also incorporated to insure that the mart ensite-parent interface is semicoherent and glissile. These factors an d the orientation relationship as well are uniquely interrelated withi n the theoretical framework and must be so for any transformation alle ged to follow the theory.