M. Ichinose et al., MORPHOLOGICAL STABILITY OF GAMMA ALPHA-INTERFACE FORMED BY CARBURIZATION IN FE-C-X ALLOYS/, Metallurgical and materials transactions. A, Physical metallurgy andmaterials science, 25(3), 1994, pp. 531-537
Effect of alloying elements on the morphological stability of austenit
e/ferrite interface formed by carburization of Fe-X alloys at 850-degr
ees-C and 800-degrees-C was investigated. Planar interfaces were found
when the alloying elements added were from among the following: Ti, V
, Nb, Ta, Cr, Mo, W, Co, and Cu. Nonplanar interfaces with Widmanstatt
en-like structures and/or an isolated phase were observed when the all
oying elements were from the following group: P, Al, Sb, Ni, Mn, Si, a
nd Ge. The degree of supersaturation of C in the alpha phase adjacent
to the gamma phase front was analyzed using the concept of local equil
ibrium. It was confirmed that there was indeed a close correlation bet
ween the morphological stability and the degree of C supersaturation,
which in itself depended on whether the alloying element added was an
alpha or gamma stabilizer and how strongly it bonded with C in the fer
rite phase.