“…21,22) It is assumed that when equiaxed grain structures are obtained, the volume fraction is 0.5 (corresponding to the GTK model) and the degree of undercooling, necessary for the nucleation of δ-ferrite, is 1.0 K. Table 3 shows the incoherency of the crystal lattice of the δ phase with several types of inclusions. 7,10,23) The coherency of Al 2 O 3 was small and that of the spinel and TiN were large.…”