Patent ID: 7299854

Claim:
A method of producing 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 cooling passages and a generally vertical axis and with the shot sleeve enclosing a shot piston having cooling passages and movable axially within the sleeve, and 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 liquified molten metal, pouring the molten metal directly into the shot chamber, confining the molten metal within the shot chamber to have a horizontal width substantially greater than the vertical depth of the molten metal within the shot chamber, cooling the shot sleeve and the shot piston to cool 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 the vertical depth, solidifying a portion of the molten metal in the shot chamber to form a semi-solid slurry having at least 40% of solids and a globular and generally non-dendritic microstructure, moving the shot piston upwardly within the shot chamber to inject the semi-solid slurry from the shot chamber into the die cavity through at least one gate opening, and allowing the semi-solid slurry to solidify within the die cavity to form the metal part.