| 摘要 |
PURPOSE: To improve a service life of a metallic mold by improving the crack resistance of a base material for metallic mold and increasing the combined strength between the surface of the base material for metallic mold and a zirconia film. CONSTITUTION: The base material 11 for metallic mold is produced with a material mainly made of a low Cr.Mo cast steel containing 1.70-7.00wt.% Cr, a low Cr.low Ni cast steel containing 0.60-1.50wt.% Cr and 1.00-3.50wt.% Ni or a low Cr.low Ni Mo cast steel containing 0.25-0.55wt.% Cr, 1.00-2.50wt.% Ni. Softening treatment is executed to this base material 11 for metallic mold with heat treatment, and thermal-spraying formation of the zirconia film 12 is executed on the surface of this base material 11 for metallic mold, and this zirconia film 12 is made to be a gradient composition which is higher zirconia concn. ratio from the base material 11 for metallic mold side toward the film surface. |
