Abstract
Diffusion couples of Fe-Ni, which mean electrodeposited nickel on electrolytic iron, were studied. This paper discribes the effects of temperature and duration for heat treatment on composition, structure, hardness, etc. of diffusion layers formed. The results were summarized as follows. The diffusion layers were formed at low heat treatment temperature such as 600°C. It was shown that the nickel concentration is about 25-30wt% in diffusion layers at each treatment temperatures. Diffusion layers showed volume diffusion process in the heat treatment temperature range between 600-800°C, but it was shown grain boundary diffusion process in the temperature range between 900-1000°C. The results of hardness measurement indicated that the layer formed at lower than 800°C having a maximum value Hk=270 and at high temperature than 800°C having low value hardness such as Hk=120.
