摘要 |
A method of the surface treatment of a mold for casting, which comprises subjecting a cavity surface of a fixed mold made by the use of a SCM420 material to first shot peening, a sulfurizing-nitriding treatment and second shot peening. The resulting cavity surface of the fixed mold exhibits a high hardness of 700 or higher in terms of Vickers hardness due to the presence of a sulfurized and nitrided layer, and further has a compression residual stress of more than 1200 Mpa and a largest height, which is a surface roughness value defined by JIS standard, of 8 mum or less.
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