Patent ID: 6808004
Filing Date: 2004-10-26
Classification: B22D,Y10S

Abstract:
A method of semi-solid molding a high strength metal part within a die cavity defined by a die set mounted on a vertical die cast press, the press including a shot sleeve having a generally vertical axis and enclosing a shot piston movable axially within the sleeve with the sleeve and piston defining a shot chamber above the piston, the method comprising the steps of:melting a solid metal to form a molten metal, treating the molten metal with a grain refiner, transferring the molten metal into the shot chamber, cooling the molten metal within the shot chamber to within a predetermined temperature range while the molten metal within the shot chamber has a horizontal width substantially greater than its vertical depth and without stirring the molten metal to form a substantially quiescent and shallow semi-solid slurry having a globular and generally non-dendritic microstructure, moving the shot piston upwardly within the shot chamber to inject a central portion of the semi-solid slurry from the shot chamber into the die cavity through a gate opening within a central portion of the shot chamber, and allowing the semi-solid slurry to solidify within the die cavity to form the metal part.