Gm Global Technolgoy Operations, Inc.

Louisiana State University and Agricultural & Mechanical College

Wen Jin Meng

Gary L Doll

Stephen Joel Harris

Swathy Swathirajan

Yang Li

Fanghua Mei

Yang-Tse Cheng

Thomas Hubert Van Steenkiste

George Albert Drew

John Robert Smith

Bryan A Gillispie

Compression molding of metals is used to make microchannel heat exchangers. Heat transfer can be improved by employing controlled microchannel surface roughness. Flux-free bonding is achieved using a eutectic thin-film intermediate layer. Seals are leak-tight, mechanically strong, and uniform across multiple contact areas. The metal heat exchangers may be mass-produced inexpensively, and are useful for applications including the cooling of computer chips and other high-power electronic devices, air conditioning, refrigeration, condenser plates, radiators, fuel cell heat management, and instant water heating.

Metal-based microchannel heat exchangers made by molding replication and assembly

A process is disclosed for producing metal-based, high-aspect-ratio microscale structures (HARMs), for example microchannels in a heat exchanger. The preferred manufacturing method operates in a continuous mode, and employs low-temperature rolling of metals. A process is disclosed for bonding metal microchannel sheets or plates to flat metal sheets or plates to form single-, double-, and multiple-layered microchannel structures. The process can operate at much lower temperatures than prior methods of compression microscale molding of metals, at room temperature or even lower.

Continuous microscale forming of metal-based microchannels and other microchannel devices

An inexpensive method of rapidly fabricating reactive metal (Zn, Al, Al-alloy, etc.) microscale structures including high-aspect-ratio microscale structures is disclosed. A high precision process uses conformal bond inhibitor coating and high temperature compression molding techniques to produce high quality, high aspect ratio metal structures. In one embodiment, following fabrication of an initial metallic microscale mold insert, an adhesion-promoting metal precursor layer and a ceramic bond inhibitor coating are conformally deposited onto the microscale mold insert. The microscale mold insert and a preselected reactive metal are then heated to an optimum temperature and compressed together. The mold insert is then extracted from the molded metal to produce a reverse image of the mold insert.

Microscale compression molding of metals with surface engineered LIGA inserts

The present invention contemplates a PEM fuel cell having electrical contact elements (including bipolar plates/septums) comprising a titanium nitride coated light weight metal (e.g., Al or Ti) core, having a passivating, protective metal layer intermediate the core and the titanium nitride. The protective layer forms a barrier to further oxidation/corrosion when exposed to the fuel cell's operating environment. Stainless steels rich in CR, Ni, and Mo are particularly effective protective interlayers.

Corrosion resistant PEM fuel cell

Electroplated chromium coatings on automobile suspension damper piston rods are replaced with thermal or kinetic spray coatings of: (a) suitable corrosion-resistant metal alloys such as iron and chromium containing nickel-based alloys or chromium containing steels, or (b) suitable ceramic coatings such as electrically insulative alumina ceramics. The spray coatings are porous, and the metal alloy coatings usually should be sealed for corrosion protection.

Spray coatings for suspension damper rods

An electrical terminal is disclosed where the terminal is formed of an electrically-conductive metal substrate such as copper alloys, aluminum alloys or stainless steel with the substrate having a codeposited composite coating of titanium nitride and gold or silver on the surface. The coating provides wear resistance in high temperature and vibration environments while retaining and demonstrating low friction and low contact resistance properties.

Growing community of inventors

Baton Rouge, LA, United States of America

Wen Jin Meng