Method and apparatus for manufacturing aluminum die-cast product

Abstract

A method and an apparatus for manufacturing an aluminum die-cast product are provided, wherein an occurrence of shrinkage cavity is eliminated or reduced to a very small amount, and a sound and high-quality aluminum die-cast product having no casting defect can be produced. The method for manufacturing an aluminum die-cast product by performing die casting while a part, in which a casting defect tends to occur due to solidification shrinkage of a melt, which has been pressure-filled in a mold, during a solidification process, is pressurized with a local pressurization pin includes the steps of allowing the local pressurization pin to follow the movement of a solidification interface based on a solidification interface movement speed, which is calculated in advance, of the melt and keeping pushing the local pressurization pin in until the solidification is completed.

1 . A method for manufacturing an aluminum die-cast product by performing die casting while a part in which a casting defect tends to occur due to solidification shrinkage of a melt, which has been pressure-filled in a mold, during a solidification process is pressurized with a local pressurization pin, the method comprising the steps of:
 allowing the local pressurization pin to follow the movement of a solidification interface based on a solidification interface movement speed, which is calculated in advance, of the melt; and   keeping pushing the local pressurization pin in until the solidification is completed.   
   
   
       2 . The method for manufacturing an aluminum die-cast product according to  claim 1 , wherein the pressurization with the local pressurization pin is started 0.4 to 1.4 seconds after the filling of the melt is completed. 
   
   
       3 . The method for manufacturing an aluminum die-cast product according to  claim 1 , wherein the average push-in speed V of the local pressurization pin is specified to be 1.2 mm/s<V<2.63 mm/s. 
   
   
       4 . The method for manufacturing an aluminum die-cast product according to  claim 1 , wherein the aluminum die-cast product is a pressure vessel. 
   
   
       5 . The method for manufacturing an aluminum die-cast product according to  claim 4 , wherein the pressure vessel is a housing of a compressor. 
   
   
       6 . An apparatus for manufacturing an aluminum die-cast product by performing die casting while a part, in which a casting defect tends to occur due to solidification shrinkage of a melt, which has been pressure-filled in a mold, during a solidification process, is pressurized with a local pressurization pin, the apparatus comprising:
 the local pressurization pin disposed in accordance with the part, in which the casting defect tends to occur, so as to locally pressurize the part;   a push-in device for pushing the local pressurization pin in toward the part; and   a control portion for controlling the push-in device in such a way that the local pressurization pin is allowed to follow the movement of a solidification interface based on a solidification interface movement speed, which is calculated in advance, of the melt and the local pressurization pin is kept being pushed in until the solidification is completed.   
   
   
       7 . The apparatus for manufacturing an aluminum die-cast product according to  claim 6 , wherein:
 an overflow portion in accordance with the part, in which the casting defect tends to occur, is disposed in the mold;   the local pressurization pin is attached in such a way that the local pressurization pin can be pushed in the overflow portion; and   the overflow portion is locally pressurized with the local pressurization pin.