焼結鋼におけるモリブデンの拡散合金化過程 Ｉ 鉄‐モリブデン‐炭素系圧粉体拡散対における合金化過程

Abstract

In order to reveal the diffusion processes of molybdenum in sintered steels, diffusion couples prepared from powder mixture compacts were heated in vacuum at 1523K for 3.6ks, and the diffusion zones were examined mainly by means of EPMA.Carbon in the iron-molybdenum diffusion couples intensively affected the diffusion layer formation through the carbide layers formation. In the diffusion couples containing carbon, the molybdenum diffusion in iron was considerably enhanced by using Mo2, C powder compacts as the coupling partner for iron powder compact or iron-carbon powder mixture compact, as compared with the use of molybdenum and graphite powder mixture compacts of the same composition. The difference in the degree of molybdenum diffusion was attributed to the iron-molybdenum-carbon ternary liquid phase formation in the interface of diffusion couple, as well as the diffusion in the solid phase.