| 摘要 |
PURPOSE:To stably form a chill hardened layer based on cementite, in hardening the spacific surface of a cast iron member by chilling, by melting a filler material containing a cementite stabilizing element in the surface to be hardened of the cast iron member after preheating before cooling said member. CONSTITUTION:In forming a surface having high hardness and excellent abrasion resistance such as the slide surface of cast iron parts, the cast iron member 1 is preheated to 150-600 deg.C. Next, a filler material 2 containg a while pig iron forming promotor selected from B, Te, Bi, Cr, Mo, Ni and Ti is placed on the surface to be hardened of said member and the cast iron surface is melted along with the filler material 2 by a TIG welding apparatus 3 to contain the above mentioned white pig iron forming promotor in an eutectic state before cooling. By this method, a chill hardened layer alpha is formed to the surface and the hardness thereof is remarkably enhanced to enhance abrasion resistance. |
