| 摘要 |
PURPOSE:To obtain a cast iron article with high surface hardness and satisfactory toughness by irradiating laser light on the surface of a cast iron article to harden the surface and by subjecting the article to graphitizing heat treatment. CONSTITUTION:Laser light is irradiated on the surface of a cast iron article such as a roll of high-Ni austenitic spheroidal graphite cast iron. A very thin layer close to the surface is rapidly melted, and the molten layer is rapidly solidified to harden the surface. The case iron article is then subjected to graphitizing heat treatment at 950 deg.C for 4hr. By this method a cast iron article with high surface hardness and satisfactory toughness is obtd. |
