Gm Global Technolgoy Operations, Inc.

Guangling Song

Blair E Carlson

Yar-Ming Wang

Anil Kumar Sachdev

Jon T Carter

Jan F Herbst

Hong-Hsiang Kuo

Mark William Verbrugge

Arun Kumar

Dale A Gerard

Bob Ross Powell

Xiaohong Gayden

Aihua A Luo

William A Schumacher

Deepika Sachdeva

Pui-Kei Yuen

Ping-Ho Tsai

Kevin M Cunningham

David L Moore

Zhengwen Pu

Johnnie M Williams

A method of preparing a magnesium alloy substrate for an electroless electro-deposition surface treatment includes cleaning the magnesium alloy substrate in a wet solution, whereby a magnesium hydroxide layer is formed on an outer surface of the magnesium alloy substrate, and heating the magnesium alloy substrate to a temperature sufficient to convert the magnesium hydroxide layer to a magnesium oxide layer.

Method of preparing a magnesium alloy substrate for a surface treatment

A body panel assembly and a method for manufacturing a body panel assembly are disclosed herein. In a non-limiting embodiment, the body panel assembly includes, but is not limited to, an inner panel having a lower portion. The body panel assembly further includes an outer panel that is connected to the inner panel. The outer panel has a main portion, a transitional portion, and a bent portion. The main portion and the bent portion are positioned on opposite sides of the lower portion. The main portion, the transitional portion, and the bent portion are arranged to form a cavity having an elongated configuration below the inner panel. The bent portion defines an opening extending therethrough. The opening is positioned at least partially below the lower portion of the inner panel. The opening provides ventilation to the cavity.

Body panel assembly and a method for manufacturing a body panel assembly

The corrosion resistance of formed and shaped sheet magnesium alloy articles may be improved by applying to the article a substantially crack- and pore-free ductile metal layer on at least selected surfaces and cut or sheared edges. An exemplary ductile metal may be aluminum or its alloys. Two methods of applying such a ductile metal layer are described. One method is suitable for extended areas of the magnesium alloy surface, and is applied prior to stamping the article while a second method, suitable for cut or sheared edges, is intended for application after the article is fully formed. The incorporation of both embodiments into conventional sheet metal stamping processes to form the corrosion resistant formed magnesium article is described.

Corrosion resistant magnesium article method of making

Methods of providing a corrosion-resistant plating on a steel bumper are provided. A galvanized zinc layer is deposited over a steel substrate. A plurality of nickel layers is deposited over the zinc layer. The plurality of zinc layers has at least a first porosity and a second porosity. A chrome layer is applied over the plurality of nickel layers. The porous nickel layer is immediately adjacent the chrome layer such that a stress applied to the chrome layer is distributed over the porous nickel layer. The porous nickel layer delocalizes a stress applied at an impact area to a dispersed area and the dispersed area is larger than the impact area.

Corrosion-resistant plating system

Surfaces of magnesium-base alloy workpieces may be mechanically worked and deformed to increase their resistance to corrosion, especially corrosion occurring in the presence of water or water and salt or other corrosive media. Workpiece surfaces that are to be thus protected are engaged in squeezing, sliding, and frictional contact with a suitable burnishing or other working tool that traverses the surface to compress and deform it and to refine the metallurgical grain structure. For example, the grain size is reduced in a surface layer that may extend to a depth of up to a few millimeters. And grain orientation is altered within that depth. The tool is not employed to intentionally remove material from the surface of the workpiece. The initial dimensioning of the workpiece may take into consideration the alteration of surfaces by the mechanical working process.

Corrosion resistance of magnesium alloy article surfaces

A sealed hemmed closure assembly includes an inner panel having a first face and a second face, and an outer panel having a panel portion and a hemming portion. The second face of the inner panel substantially opposes the first face, and the hemming portion of the outer panel is disposed proximate an edge of the outer panel. The panel portion of the outer face is configured to abut the first face of the inner panel, and the hemming portion is configured to abut the second face of the inner panel. An adhesive material is disposed between the panel portion of the outer panel and the first face of the inner panel, and a sealant material is disposed between the hemming portion of the outer panel and the second face of the inner panel.

System and method for sealing a hemmed closure

A valve for an anti-lock brake system, wherein the anti-lock brake system is configured for controlling flow of a fluid, includes a housing defining a cavity therein and having a longitudinal axis, a valve seat disposed within the cavity so as to define a first passage for the fluid, and an armature disposed within the cavity so as to at least partially define a second passage for the fluid. The armature is translatable with respect to the valve seat along the longitudinal axis and matable with the valve seat to seal off fluid communication between the first passage and the second passage. The armature defines a surface that is substantially resistant to corrosion from the fluid, and the surface is substantially free from a coating including zinc.

Corrosion-resistant armature and valve for anti-lock brake systems

Methods of coating a magnesium substrate are provided along with coated magnesium substrates. A low melting point material is cold sprayed onto a region of the magnesium substrate. A corrosion resistant material or a zinc material is cold sprayed over at least a portion of the low melting point material to form a coated magnesium substrate. The coated magnesium substrate is then heated.

Cold sprayed and heat treated coating for magnesium

Iron impurities may be removed from volumes of molten aluminum or magnesium metals or alloys by applying a static magnetic field gradient to each of the molten metal volumes, or melts. The magnetic field gradient is applied to each of the melts so that separate-phase iron impurities suspended therein will move in the direction of the applied magnetic field and become concentrated in a predetermined region of the of the melts, thereby forming an iron-rich region. The remaining iron-depleted region of each of the melts can be physically separated from the as-formed iron-rich region and cast into shaped articles of manufacture or into semi-finished articles for further processing. Such articles will have a lower iron-content than the original molten metal volumes.

Magnetic separation of iron from aluminum or magnesium alloy melts

A method is disclosed for improving the corrosion behavior of cast magnesium alloy articles in which the magnesium alloy comprises an average composition of more than about 5 per cent by weight of aluminum. A microstructure with regions of varying aluminum content is developed during solidification. The microstructure comprises magnesium-rich grains generally surrounded by an aluminum-enriched phase on the boundaries between adjacent grains. The magnesium-rich grain interiors are then selectively chemically or electrochemically attacked to leave a more corrosion resistant aluminum-enriched surface on the articles. The corrosion resistance of the articles may be further enhanced by one or more of anodizing, aluminizing or painting the corrosion-resistant aluminum-enriched surface.

Surface treatment of magnesium alloy castings for corrosion protection

A method of manufacturing a closure assembly for a vehicle includes trimming an outer panel to define a first edge and trimming an inner panel to define a second edge, wherein the outer panel is formed from an aluminum alloy material and the inner panel is formed from a magnesium alloy material. The method further includes chemically shaping the second edge to define a substantially rounded edge surface having a radius, positioning the inner panel adjacent the outer panel such that the first edge extends beyond the substantially rounded edge surface, and bending the first edge of the outer panel around the substantially rounded edge surface of the inner panel to form a hem connection that secures the inner panel relative to the outer panel. A closure assembly is also disclosed.

Closure assembly and method of manufacturing same

The surface composition of a metal article may be modified by depositing a coating layer material of a different composition from a consumable tool which is urged against the article surface while being rotated about an axis generally normal to the surface. The frictional heating resulting from rotation of the tool under applied pressure increases the temperature of the article-contacting portion of the tool so that it adheres to and bonds to the magnesium alloy article. In an embodiment the tool material is selected to be more corrosion-resisting than or sacrificial to the substrate metal alloy. In another embodiment the tool material is selected to react with the magnesium surface to form a more corrosion-resistant coating or a sacrificial layer. In another embodiment a holemaking cutting tool may be incorporated in to the consumable tool to enable fabrication of a hole with a surrounding, more corrosion-resistant annular surface. Further processing of the article with its coating layer may include: buffing, burnishing, or polishing the layer; and heat treatment to promote diffusion of the layer composition into the article composition.

Consumable tool friction stir processing of metal surfaces

An engine includes a cylinder head at least partially defining a valve seat pocket. A valve seat is located proximate to the cylinder head to at least partially define the valve seat pocket. A pocket filler is located between the valve seat and the pocket insert such that the pocket filler occupies a substantial portion of the valve seat pocket. A pocket insert is attached to the cylinder head proximate to the valve seat pocket, such that the pocket insert lines at least a portion of the valve seat pocket.

Corrosion resistant insert for a cylinder head

A system for detecting and preventing galvanic corrosion of an anodic metal includes a potential detector configured to monitor an electrical potential within the electrolyte solution, a signal amplifier coupled with the potential detector, and a current delivery circuit coupled with the signal amplifier. The signal amplifier is configured to provide an output proportional to the monitored electrical potential, and the current delivery circuit is configured to provide a current to a cathodic metal that is proportional to the output of the signal amplifier.

Growing community of inventors

Troy, MI, United States of America

Guangling Song