Creation of slots on the surface of a core

Abstract

The invention relates to a foundry core for cast pieces of aluminium alloy in a mold, said core comprising a molding part, intended to be in contact with the molten aluminium alloy, and at least one non-molding part intended to be located outside the molten aluminium alloy, the core comprising at least one slot on the surface of the core, said slot extending from the molding part to at least one non-molding part for discharge of the gases generated in the molding part of the core during casting outside the molding part.

1 . A foundry core ( 10 ) for casting pieces of aluminium alloy in a mold ( 20 ), said core ( 10 ) comprising:
 a molding part ( 11 ), intended to be in contact with the molten aluminium alloy ( 30 ),   at least one non-molding part ( 12   a ), intended to be located outside the molten aluminium alloy ( 30 ),   characterized in that the foundry core ( 10 ) comprises at least one slot ( 13 ) on the surface of the core ( 10 ), said slot ( 13 ) extending from the molding part ( 11 ) to at least one non-molding part ( 12   a ) for discharge of the gases generated in the molding part ( 11 ) of the core ( 10 ) during casting outside the molding part ( 11 ).   
     
     
         2 . The foundry core ( 10 ) according to  claim 1 , wherein the non-molding part(s) ( 12   a ) are core prints ( 12   b ), adapted to keep the core ( 10 ) in position inside the mold ( 20 ). 
     
     
         3 . The foundry core ( 10 ) according to any one of the preceding claims, wherein the slots ( 13 ) have a width ( 13   a ) adapted to prevent the molten aluminium alloy ( 30 ) from entering inside said slot ( 13 ). 
     
     
         4 . The foundry core ( 10 ) according to any one of the preceding claims, wherein the slots ( 13 ) on the surface have a width ( 13   a ) less than 1 mm and preferably 0.2 mm. 
     
     
         5 . The foundry core ( 10 ) according to any one of the preceding claims, wherein the slots ( 13 ) have a rectangular geometric, U-shaped or V-shaped profile. 
     
     
         6 . The foundry core ( 10 ) according to any one of the preceding claims, wherein the slots ( 13 ) have an average depth ( 13   b ) of between 0.2 and 2 mm, to allow the gases generated in the molding part ( 11 ) of the core ( 10 ) to circulate in the slots ( 13 ). 
     
     
         7 . The foundry core ( 10 ) according to any one of the preceding claims, wherein the slots ( 13 ) are made by laser. 
     
     
         8 . The foundry core ( 10 ) according to any one of  claims 1  to  6 , wherein the slots ( 13 ) are made by tooling with reliefs in the shape of blades. 
     
     
         9 . A mold adapted for casting foundry pieces, comprising a core ( 10 ) according to any one of the preceding claims. 
     
     
         10 . The mold according to the preceding claim, further comprising a suction system ( 43 ) adapted to suction in the slots ( 13 ) the generated gases, with suction occurring at the non-molding zones ( 12   a ). 
     
     
         11 . A method for manufacturing a core ( 10 ), according to any one of  claims 1  to  8 , characterized in that it comprises an etching step of said slots ( 13 ) on the surface of the core ( 10 ) by means of a laser ( 5 ). 
     
     
         12 . The method for manufacturing a piece of aluminium alloy by casting molten metal by means of a mold according to one of  claims 9  to  10 . 
     
     
         13 . A cylinder head for an automobile obtained by a method according to the preceding claim. 
     
     
         14 . An engine block for an automobile obtained by a method according to  claim 12 .