T.h.t. Presses, Inc.

Reynolds Metals Company

Cmi International, Inc.

John L Jorstad

Richard J Kamm

William H Overbagh

Richard A Morley

Richard A Morely

George W Steele

Thomas P Schneider

A metal alloy is heated to a molten state, and a grain refiner may be added. The molten alloy is poured into a shallow chamber of a shot sleeve of a vertical die cast press and on top of a shot piston. The shot sleeve is transferred to an injection station while the molten alloy cools to a semi-solid slurry with a globular, generally non-dendritic micro structure. An inner portion of the shallow slurry is injected upwardly by the piston through a gate opening into a die cavity while an outer more solid portion of the slurry is entrapped in an annular recess. After the slurry solidifies, the shot piston retracts, and the shot sleeve is transferred to a position where the residual biscuit is removed. The shot piston may have internal grooves to provide a large heat transfer area for cooling water to absorb heat from the molten alloy.

Semi-solid molding method

A metal alloy is heated to a molten state and is poured into a shot sleeve of a vertical die cast press and on top of a shot piston. The shot sleeve is transferred to an injection station while the molten alloy is cooled to a semi-solid slurry and a globular, generally non-dendritic microstructure. A retractable cooling pin is temporarily inserted into a center portion of the slurry while in the shot sleeve to obtain optimum cooling. A center portion of the slurry is injected upwardly by the piston through a gate opening into a die cavity while an outer more solid portion of the slurry is entrapped in an annular recess. After the slurry solidifies, the shot piston retracts, and the shot sleeve is transferred to a position where the residual biscuit is removed. Another shot sleeve filled with the molten allow is transferred, and the process is repeated.

Semi-solid molding apparatus and method

A metal alloy is heated to a molten state, and a grain refiner may be added. The refined molten alloy is poured into a large diameter shot sleeve of a vertical die cast press and on top of a shot piston. The shot sleeve is transferred to an injection station while the molten alloy cools to a semi-solid slurry with approximately fifty percent solids and a globular, generally non-dendritic microstructure. A center portion of the slurry is injected upwardly by the piston through a gate opening into a die cavity while an outer more solid portion of the slurry is entrapped in an annular recess. After the slurry solidifies, the shot piston retracts, and the shot sleeve is transferred to a position where the residual biscuit is removed. A second shot sleeve filled with the molten alloy is transferred to the metal transfer station, and the process is repeated.

A composite metallic cast article (A) includes a shell (28) having a predetermined solid phase density. A non removable insert (24) is at least partially embedded within the shell (28). The insert (24) is fabricated from a foamed metal substance having a substantially lower solid phase density than the shell (28). The foamed metal insert (24) may have a layer of skin (26) fused with the molten metal of the shell (28) during the casting process. Tapered locating pins (30) or other spacing elements position the insert (24) within the mold cavity (18) to prevent shift during the casting operation. The foamed metal insert (24) reduces the time and expense involved in removing a traditional casting core after the casting operation is complete. Also, the insert (24) can be completely enclosed within the shell (28) of the article (A), thereby expanding the design capabilities of such cast articles (A). Furthermore, the foamed metal insert (24) provides better stiffness and energy absorbsion to the cast article (A) when compared with a hollow cavity section formed by a core of the prior art.

Method of making a casting having a low density insert

Processes for coating a ferrous or aluminum article, such as an engine cylinder liner insert, to provide a metallurgical bond with aluminum alloy material cast around the article. The article surface to be bonded is treated to remove impurities, oxides, and foreign materials, and the article is preheated. A molten metallic bonding material, such as zinc or a zinc alloy, is provided and the treated and preheated article is immersed in the bonding material to provide a metallurgically bonded coating on the surface of the article being treated. The coated article, either shortly after coating or, alternatively, after having been cooled to ambient temperature and stored, can then be placed in a mold and molten aluminum alloy poured around it to metallurgically bond the aluminum to the coating on the article. The resulting structure provides a metallurgical bond that has improved heat transfer characteristics and improved structural integrity. The invention also provides improved assemblies having metallurgically bonded components, such as an engine block having metallurgically bonded cylinder liners.

Process for creation of metallurgically bonded inserts cast-in-place in

An engine block for an internal combustion engine including at least one bore, and a cylindrical liner that is pressed into the bore to define the inner cylindrical surface along which the piston reciprocates. The inner surface of the bore and the outer surface of the liner are each coated with a zinc or zinc alloy coating that is metallurgically bonded to the respective surfaces to form intermetallic bonds. The liner is pressed into the bore while the liner and bore are at an elevated temperature approximately corresponding to the melting temperature of zinc, in order to unite the liner and block by means of a metallurgical bond. The metallurgical bond is substantially continuous to provide a continuous metallic path for improved heat transfer and structural strength between the liner and the block material. The liner can be formed either from cast iron or from an aluminum alloy, and the engine block is preferably cast from an aluminum alloy.

Growing community of inventors

Richmond, VA, United States of America

John L Jorstad