Distribution of Nitrogen Diffusion Study Through Layer Surface of α – Iron

This paper aims to study the distribution of free nitrogen atoms through surface of α – Fe sample using the numerical solution for linear differential equation by means of Crank – Nicolson method at a temperature range ( 550 to 950 0C) and time interval (0 – 8)h where the nitrogen diffusion constant is at 850 0C and 8h. Under the supposed condition this study has illustrated that the diffusion depth of nitrogen atoms from surface towards inners reaches to ̴ 1.2mm, i.e., determining the layer thickness of the formed nitride compounds which gives the surface layer of α – Fe high resistance against corrosion processes resulting from surrounded environment.