Film and method for manufacturing same

Abstract

Disclosed are a film with high strength which does not easily deteriorate, and a method for manufacturing the film. A step for manufacturing a film formed on the molding surface of a die, includes an initial film-forming step for forming, on the molding surface of the die, an initial film having a carbon film which has a plurality of nano-carbons, and to which a plurality of fullerenes are applied, and a nitrogen compound layer and a sulfurized layer which are situated between the carbon film and the die, and an intermittent heating step for intermittently heating the initial film formed in the initial film-forming step under a non-oxidizing atmosphere.

1 - 4 . (canceled) 
     
     
         5 . A method for manufacturing a film formed on a molding surface of a die used for casting, comprising:
 an initial film-forming step for forming, on the molding surface of the die, an initial film including a carbon film, a nitrogen compound layer and a sulfurized layer, the carbon film having a plurality of nano-carbons, and a plurality of fullerenes which is applied to the carbon film, the nitrogen compound layer and the sulfurized layer being situated between the carbon film and the die; and   an intermittent heating step for intermittently heating the initial film formed in the initial film-forming step under a non-oxidizing atmosphere, wherein   in the intermittent heating step, an oil-based release agent is applied to the molding surface of the die on which the initial film is formed, and then the casting is performed a plurality of times using the die.   
     
     
         6 . A film which includes a carbon film having a plurality of nano-carbons, and which is formed on a surface of an iron-based material, characterized by
 containing hard amorphous carbon, Fe 4 N, Fe 3 C, martensite, and Fe 3 O 4 , and   sulfur-diffusion ratio in the carbon film which is over 50%.   
     
     
         7 . The film according to  claim 6 ,
 wherein said hard amorphous carbon, Fe 4 N, Fe 3 C, martensite, and Fe 3 O 4  are identified by an X-ray diffraction method, and   the sulfur-diffusion ratio is found by mapping analysis with an EPMA.