2013.    KURDYUMOV, G., AND SACHS, G.  [Mechanism of Steel Hardening.]  Naturwissenschaften, vol. 18, 1930, p. 534; Chem. Abs., vol. 24, 1930, p. 4746.

      Mixture of austenite and martensite crystals from slow solidification and subsequent chilling of a 1.5% C steel was studied for crystal nature and orientation.  The (011) plane of the tetragonal crystallites always was parallel to the (111) planes of austenite, also (111) direction to (101), giving an 8° angle between tetragonal axis and austenite axis.  This position repeats itself 24-fold in agreement with general cubical symmetry.  It can be derived from a superposition of 2 simple slip motions.