摘要:
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 (Ac3 temperature). The steel workpiece is then cooled just below its Ac3 temperature to promote ferrite formation on and between the austenite grains. Heating and cooling, above and below the Ac3 temperature, 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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
This invention relates to an apparatus for sensing a vehicle steering wheel position. A permanent magnet target wheel having a global axial magnetic field normal to a first surface is attached to a steering shaft which is rotated by the steering wheel. Multiple regions equally spaced along a common radius on the first surface are magnetically altered and sensed by magnetically responsive sensors positioned adjacent the first radius. A single region positioned within a finite radius along a second radius on the first surface is magnetically altered and sensed by a magnetically responsive sensor positioned adjacent the second radius. The magnetic sensors are responsive to passage of the multiple regions and single region as the target wheel is rotated. Detection of each of the multiple regions corresponds to rotation of the target wheel by an incremental number of degrees. Detection of the single region corresponds to a target wheel position within a predetermined angular range, referred to as the center position. A turn counter is utilized to determine which of the center positions corresponds to the steering wheel neutral position.
摘要:
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.
摘要:
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.
摘要:
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.