Mold device

Abstract

A mold device is capable of producing a member formed from aluminum, and includes a mold and a molten metal supply part. The mold is capable of forming a cavity into which molten aluminum is charged. The mold has a base part formed from iron and a surface layer part. The surface layer part is provided on the cavity side of the base part and contains 20 weight % or more of chromium. A dichromium trioxide film is formable on a surface of the cavity side of the surface layer part. The molten metal supply part is capable of supplying molten aluminum into the cavity.

What is claimed is: 
     
         1 . A mold device that is capable of producing an aluminum die-cast member, comprising:
 a mold capable of forming a cavity into which molten aluminum is charged and has a base part formed from iron and a surface layer part, the surface layer part being provided on the cavity side of the base part, containing 20 weight % or more of chromium, and being capable of forming a dichromium trioxide film on a surface of the cavity side; and   a molten metal supply part capable of supplying molten aluminum into the cavity, wherein   the mold has a concentration transition part that is provided between the base part and the surface layer part and in which a chromium concentration constantly increases from the base part toward the surface layer part, and   the base part, the concentration transition part, and the surface layer part are integrally formed.   
     
     
         2 . A mold device that is capable of producing an aluminum die-cast member, comprising:
 a mold capable of forming a cavity into which molten aluminum is charged and has a base part formed from iron and a surface layer part, the surface layer part being provided on the cavity side of the base part, containing 20 weight % or more of chromium, and being capable of forming a dichromium trioxide film on a surface of the cavity side;   a molten metal supply part capable of supplying molten aluminum into the cavity, and   an oxidant supply part capable of supplying an oxidant onto the surface of the surface layer part on the cavity side.   
     
     
         3 . The mold device according to  claim 2 , wherein the oxidant is an oxidizing acid. 
     
     
         4 . The mold device according to  claim 1 , wherein the surface layer part has a thickness of 30 μm or more and 200 μm or less. 
     
     
         5 . The mold device according to  claim 1 , wherein the base part has a carbon concentration of 0.07 weight % or less.