Gm Global Technolgoy Operations, Inc.

Other

Hughes Aircraft Company

The Ohio State University

Delco Electronics Corporation

John Robert Bradley

Thomas Arthur Perry

Thaddeus Schroeder

John E Carsley

Bruno P Lequesne

James Gregory Schroth

Richard Harry Hammar

Glenn S Daehn

Carlton D Fuerst

Mark William Verbrugge

Mahmoud H Abd Elhamid

Paul Edward Krajewski

Gerald W Fly

William C Lin

Richard Murray Kleber

Joseph Pierre Heremans

Steven J Spencer

Raymond O Butler, Jr

Arianna T Morales

Thomas Hubert Van Steenkiste

Siguang Xu

James C O'Kane

Andrzej M Pawlak

Jeffrey A Sell

Yang T Cheng

Chongmin Kim

David W Graber

Martin Stephen Meyer

Gary G Tibbetts

Kevin R Marks

Anthony L Marks

Terry Andrew Kent

Frank J Bohac, Jr

Dennis C Eckhardt

Michael H Lovell

Richard Earl Teets

Scott E Weiss

Kevin K Parkila

Kenneth G Danaj

Everett K Shelton

Maged Radamis

Jacob Lyjak

Manfred W Reissmueller

Hiro Yamasaki

Donald W Cotton

Dozier: James R

Jerry S Roach

Robert A Frosch

George K Nurminen

James M Burkstrand

Jeffrey M Scramlin

One exemplary embodiment discloses a bipolar plate assembly including a cathode plate and an anode plate. Each of the cathode plate and the anode plate includes a core material, a first surface material coupled to a first side of the core material, and a second surface material coupled to a second side of the core material, wherein the first surface material and the second surface material have a different composition from the core material.

Fuel cell plates produced from layered materials

A bipolar plate used in a fuel cell and a method of making a bipolar plate. The sheet is made from a ferritic or austenitic stainless steel, and defines an undulated surface pattern such that the patterned sheet may be formed into the bipolar plate. In one configuration, a stamping or related metal forming tool operation will further deform the patterned sheet into the bipolar plate shape such that the wall thickness is substantially uniform throughout the surface. In this way, there is a substantial reduction in stretching/thinning/necking at an intersection between bends and side walls that define the undulations of the pattern. In one form, the pattern defines a repeating serpentine shape. In a particular embodiment, the bends may include surface modifications to reduce the effects of sheet-to-tool misalignment.

Unique pre-form design for two-step forming of stainless steel fuel cell bipolar plates

The microstructure of a low alloy steel workpiece for cold forming may be beneficially modified by heating the workpiece to a temperature just above its austenite transformation temperature (Actemperature). The steel workpiece is then cooled just below its Actemperature to promote ferrite formation on and between the austenite grains. Heating and cooling, above and below the Actemperature, is repeated a determined number of times to refine the austenite grains before the workpiece is quenched below its martensite transformation temperature to form a mixture of martensite with increased retained austenite. The workpiece may be further heated in its martensite region to increase the proportion of retained austenite before quenching the steel workpiece to an ambient temperature. The formability of the workpiece is improved, as is the strength of its formed shape.

Heat treatment for producing steel sheet with high strength and ductility

An impact beam assembly includes a beam of high-strength steel, and a pair of end brackets constructed of a dissimilar material than the high-strength steel. The brackets are locally deformed onto the beam to thereby surround a portion of the beam. Once deformed, the brackets define a flat section suitable for welding to a vehicle door panel, as well as a section for retaining the beam. The beam can include a surface feature suitable for retaining the beam to the end brackets. A method of reinforcing a vehicle door assembly includes positioning the beam with respect to the end brackets such that the brackets surround a portion of the beam, and then activating a magnetic pulse coil (MPC) to deform an overlapping portion of the brackets onto the beam. The brackets are then attached to a surface of the door assembly to reinforce the door assembly.

Mixed metal magnetic pulse impact beam

Electromagnetic forming methods suitable for creating surface features on a shape memory alloy are described. Features may be created over a range of scales, including those suitable for the generation of holographic images. Features, images, or patterns may be made capable of reversibly appearing and disappearing as a result of changes in temperature and may include temperature sensitive displays for automotive and other applications.

Embossed shape memory sheet metal article

Articles are often formed from a tubular workpiece in a process which does not usefully shape the ends of the tube. In an embodiment of the invention, tube ends may be mechanically reduced in cross section and then expanded against a secondary forming surface(s) using an electromagnetic force to obtain desired shapes for the tube ends and minimize scrapping of workpiece material.

Electromagnetic shape calibration of tubes

A multi-layer driver plate is disclosed for use in electromagnetic sheet metal forming operations. In one embodiment, the driver plate comprises a first layer characterized by low electrical resistivity and thickness for inducement and application of a suitable electromagnetic forming force, a second layer comprising an elastomeric material for compressing a sheet metal workpiece against a die surface and then regaining its original pre-forming structure, and a third layer interposed between the first layer and the second layer to protect the EMF force providing layer and to provide overall strength and durability to the EMF driver plate.

Driver plate for electromagnetic forming of sheet metal

Apparatus and methods are disclosed for applying electromagnetic force (EMF) to flanging and hemming metal panels to form a hemmed panel assembly. First and second apparatus and method steps use a translating EMF coil to flange a sheet and to finish a hem by progressive non-planar bending. An alternate embodiment uses EMF hemming for difficult-to-hem portions of a flange and optionally precedes this with conventional hemming of straight hem portions.

Electromagnetic flanging and hemming apparatus and method

A sheet material is gripped at its edges and hot blow formed by a pressurized working gas against a forming tool surface. The flow characteristics of the material are determined at increasing gas pressures over a range of temperature relevant to the forming operation. A predetermined pressure/time schedule is determined at a reference temperature for rapid shape formation of good parts on a continual basis. The process is then controlled as parts are thus formed by measuring the forming temperature of the parts and correcting the pressure time schedule, using the determined flow characteristics, for the actual temperature to achieve the desired shape evolution of the parts.

Hot blow forming control method

A scheme for electromagnetic formation of fuel cell plates is provided. In accordance with one embodiment of the present invention, a method of forming a flow field plate is provided where an electromagnetic actuator is arranged opposite a profiled surface of a die portion. The profiled surface of the die portion is configured to at least partially define a network of flow field plate flow passages. The electromagnetic actuator is configured to generate a magnetic field upon activation and a sheet of material is positioned between the electromagnetic actuator and the profiled die surface. The sheet of material is characterized by an electrical conductivity sufficient to yield a repulsive electromagnetic force between the actuator and the sheet upon activation of the actuator. The passages are formed by driving the electromagnetic actuator such that the repulsive force is of sufficient intensity to deform the sheet against the profiled die surface.

Electromagnetic formation of fuel cell plates

A method is disclosed for heating a cold worked sheet of superplastically formable metal composition to recrystallize its microstructure to a formable condition and/or to heat the sheet to a temperature for an immediate forming operation. The sheet is placed between two electrical resistance heated platens maintained at a suitable temperature for recrystallizing and/or heating the metal sheet through its side surfaces. In a preferred embodiment a critical gap is maintained between the platens and the sheet to permit rapid conductive heating of the expanding sheet without marring its surfaces.

Heating of metal alloy sheet by thermal conduction

A method is disclosed for heating a cold worked sheet of superplastically formable metal composition to recrystallize its microstructure to a suitably formable condition and further to heat the sheet to a temperature for an immediate forming operation. The method utilizes a combination of hot air convection heating and infrared radiation to rapidly accomplish the heating. High temperature infrared heating elements provide most of the energy during an initial high heating rate phase and then those elements are shut off and heating is completed with controlled temperature hot air to prevent overheating of the sheet metal.

Recrystallization of metal alloy sheet with convection and infrared radiation heating

A method is disclosed for forming a hem flange in an aluminum alloy sheet during the forming of the sheet into a panel that is intended to be attached to a second panel by hemming. The hem flange is formed by fluid pressure over a small radius tool portion to bend the flange from the sheet material and stretch the flange material below the bend to form a thinned hemline valley in the material. The original bend and thinned valley cooperate during the folding of the flange around the second panel to form a flat pinched hem without cracking or fracturing the flange material.

Flat pinch hemming of aluminum panels

The superplastic forming of suitable metal alloy sheets into strong components, such as automobile body structures or panels, is improved and accomplished faster by simultaneously forming two or more substantially identical, relatively thin sheets, preferably about 2 mm or less in thickness, rather than a single sheet of the same overall thickness. For example, two or more layers of thin AA5083 sheets can be stretched formed together at about 500&deg; C. with greater deformation and elongation than a single sheet of comparable thickness.

Superplastic multi-layer forming

Nonmagnetized permanent magnet material is heated in a pattern by a laser beam to a localized temperature above the Curie point or a temperature sufficient to reduce the coercivity sufficiently for an external field to magnetize the pattern in the direction of the field. Magnets so produced can have very high pole density, digital encoding and analog patterns having gradually varying local field strength. Alternating pole magnets of this type can be used for stepper motor magnets.

Magnetically coded device

Growing community of inventors

Clarkston, MI, United States of America

John Robert Bradley