Precision-casting core, precision-casting core manufacturing method, and precision-casting mold

Abstract

A coating layer including solely silicon alkoxide or mixed alkoxide of silicon alkoxide and aluminum alkoxide is formed on a surface of a sintered precision-casting core body mainly including silica particles so as to seal holes formed in the surface. As a result, it is possible to prevent the breakage of the core during casting.

1 . A precision-casting core obtained by forming an alkoxide coating layer including an alkoxide material on a surface of a sintered precision-casting core body mainly including silica particles. 
     
     
         2 . A precision-casting core obtained by forming an alkoxide-silica fume coating layer including an alkoxide material and silica fume of 5 to 40 wt % as the dispersion ratio on a surface of a sintered precision-casting core body mainly including silica particles. 
     
     
         3 . The precision-casting core according to  claim 1 ,
 wherein the alkoxide material includes solely silicon alkoxide or mixed alkoxide of silicon alkoxide and aluminum alkoxide.   
     
     
         4 . A precision-casting mold used to manufacture cast metal comprising:
 a precision-casting core obtained by forming an alkoxide coating layer including an alkoxide material on a surface of a sintered precision-casting core body mainly including silica particles and having a shape corresponding to a cavity inside the cast metal; and   an outer mold corresponding to the shape of the outer peripheral surface of the cast metal.   
     
     
         5 . A precision-casting core manufacturing method comprising:
 immersing a sintered body of a precision-casting core body mainly including silica particles into an alkoxide material;   drying the sintered body; and   heating the sintered body so as to form a coating layer on the surface of the precision-casting core body.   
     
     
         6 . A precision-casting core manufacturing method comprising:
 immersing a sintered body of a precision-casting core body mainly including silica particles into an alkoxide-silica fume material of an alkoxide material and silica fume of 5 to 40 wt % as the dispersion ratio;   drying the sintered body; and   heating the sintered body so as to form a coating layer on the surface of the precision-casting core body.   
     
     
         7 . The precision-casting core manufacturing method according to  claim 5 ,
 wherein the alkoxide material includes solely silicon alkoxide or mixed alkoxide of silicon alkoxide and aluminum alkoxide.   
     
     
         8 . The precision-casting core according to  claim 2 ,
 wherein the alkoxide material includes solely silicon alkoxide or mixed alkoxide of silicon alkoxide and aluminum alkoxide.   
     
     
         9 . A precision-casting mold used to manufacture cast metal comprising:
 a precision-casting core obtained by forming an alkoxide-silica fume coating layer including an alkoxide material and silica fume of 5 to 40 wt % as the dispersion ratio on a surface of a sintered precision-casting core body mainly including silica particles and having a shape corresponding to a cavity inside the cast metal; and   an outer mold corresponding to the shape of the outer peripheral surface of the cast metal.   
     
     
         10 . The precision-casting core manufacturing method according to  claim 6 ,
 wherein the alkoxide material includes solely silicon alkoxide or mixed alkoxide of silicon alkoxide and aluminum alkoxide.   
     
     
         11 . The precision-casting core according to  claim 3 ,
 wherein silicon ethoxide or silicon butoxide is used as the silicon alkoxide.   
     
     
         12 . The precision-casting core according to  claim 8 ,
 wherein silicon ethoxide or silicon butoxide is used as the silicon alkoxide.   
     
     
         13 . The precision-casting core manufacturing method according to  claim 7 ,
 wherein silicon ethoxide or silicon butoxide is used as the silicon alkoxide.   
     
     
         14 . The precision-casting core manufacturing method according to  claim 10 ,
 wherein silicon ethoxide or silicon butoxide is used as the silicon alkoxide.