CO-N₂雰囲気における鉄の浸炭速度に及ぼす表面性状の影響

抄録

Carburization of iron having different surface characteristics has been studied under CO-N₂ atmospheres at 1173∼1203 K by using an automatic microbalance. The initial rate of carburization of shaved or ground iron specimen was about two times larger than that of cold-rolled specimen. The higher the purity of iron, the faster the initial rate of carburization. The initial rate of the cold-rolled pure iron as shaved was eight times larger than that of cold-rolled commercial iron. Existence of catalyst such as platinum on surface was effective for increasing the rate of carburization. The initial rate of the cold-rolled pure iron as shaved and wound with platinum wire under 34.4%CO-N₂ atmosphere was approximately equal to that of cold-rolled pure iron under 81.3%CO-N₂ atmosphere. The results are discussed on the basis of a kinetic equation that was derived by solving the Fick’s diffusion equation in the presence of surface reaction.