THE LIQUID-FILM MIGRATION IN A SINTERED FE-CR-C BASE ALLOY

In an Fe-5Cr-1Mo-2Cu-0.5P-3C (wt pet) alloy prepared by liquid-phase s intering at 1120 degrees C, the intergranular liquid films migrate dur ing cooling and isothermal heat treatment at temperatures where the so lid and liquid phases coexist. The liquid film migration (LFM) occurs extensively even during rapid cooling, apparently because of a large d riving force. The migrating liquid films solidify to form network carb ides. In the regions swept by the migrating liquid films, the concentr ations of the substitutional solute atoms are slightly different from those in the original grains. When cooled rapidly, martensite is abund ant in these regions. It is possible that the driving force for LFM in this alloy stems in part from the C concentration change associated w ith the concentration changes of the slowly diffusing substitutional s olute atoms.