Abstract: The results of research on the healing in pure copper and carbon steel are shown herewith. The inner crack could be healed at elevated temperature. It suggests that the healing of long crack could depend on the "separate healing" mechanism, in which forming of partition is an haportant stage. It results in that the long crack transformed into a row of tiny smooth cracks and round holes. The diffusivity of Fe atoms to crack healing area is higher than other elements.