Casting die

Abstract

A casting die applied with laser machining and carbon-film coating on a die surface is provided with multiple grooves formed spaced at a predetermined pitch by the laser machining; multiple ridges between the multiple grooves; and multiple carbon portions buried in the multiple grooves by the carbon-film coating, wherein the die surface with the ridge and the carbon portion alternately disposed is configured such that molten metal flows thereon; the grooves are 45 μm or less in opening width and 60 μm or more in depth; and the ridge has, on a top surface thereof applied with the laser machining, multiple micro-grooves for reducing a contact area with the molten metal. The casting die is aimed to balance expanding the groove width and increasing a thickness of the carbon film and to achieve suppression of the molten metal entering into the groove and exfoliation of the carbon film.

Dependencies are inferred from the claim text.