Charles Edward Baumgartner

Molten Carbonate Fuel Cell Electrolyte Structure Fabrication Using Electrophoretic Deposition

Electrophoretic deposition has been evaluated as a technique for preparing porous LiAlO2 matrices suitable for use as molten carbonate fuel cell electrolyte structures. Although both the technique and the deposited product initially appeared to be well suited for the application, structural fracture resulted during impregnation with the alkali carbonate electrolyte necessary for fuel cell operation. Data are presented comparing and contrasting the physical properties of electrophoretically fabricated and hot-pressed electrolyte structures. 24 references.

Photo‐Selective Electroless Metal Deposition Following Light Absorption by Titanate Ceramics

Light absorption by titanate ceramics which have been pretreated with a Sn +2 containing solution can deactivate and electroless plating catalyst providing that photo-exposure occurs in an O 2 containing ambient. Conditions are described whereby a lead zirconate-titanate ceramic can be photopatterned by a brief exposure to a 365 nm wavelength lamp using a Mylar photomask and electroless Ni plated to yield a Ni pattern on the ceramic. Line/space resolution exceeding 0.05 mm is attainable

Development and thermal durability of an interfacial bond between electrolessly deposited metals and a fluorinated polyimide

The oxygen content of a fluorinated polyimide surface can be increased by exposure to an oxidant such as an alkaline permanganate solution. Deposition of an electroless metal layer on this oxidized surface results in the formation of an interfacial bond which is predominantly chemical in nature. The level of adhesion achieved depends both on the surface oxidation conditions and post-plating heating. Adhesion maxima are obtained by heating to 200°C for an electroless Cu deposit and to 300°C, the cure temperature for the polyimide film, for deposited electroless Ni. The fluorinated polyimide used in this study was derived from the reaction of 2,2-bis(4-(4-aminophenoxy)phenyl)hexafluoropropane with pyromellitic dianhydride and was obtained from Ethyl Corporation as Eymyd® L30N resin.

Electronic Conductivity Decrease in Porous NiO Cathodes during Operation in Molten Carbonate Fuel Cells

The 923 K specific electronic conductivity of 0.02 cation fraction Li-doped NiO (Li /SUB 0.02/ Ni /SUB 0.98/ O) was shown to decrease from 33.0 to 3.5 X 10/sup -2/ (..cap omega.. cm)/sup -1/ upon the addition of an equivalent doping level of Fe/sup -3/. However, the impact of this conductivity degradation mechanism on the performance of MCFCs containing Li /SUB 0.02/ Ni /SUB 0.98/ O cathodes was shown to be insignificant from iron and chromium analyses of post-tested cathodes. Although appreciable iron impurity levels were found within the NiO lattice in regions where the cathode contacted the stainless steel current collector, iron penetration into the grains was restricted to a distance of only 10 nm in 10,080h. The results indicate that impurity diffusion into the cathode should have little or no impact on fuel cell performance.

Thermosonic bonding for ultrasound transducers: Low-temperature metallurgical bonding

A low-temperature bonding process for ultrasound transducers is presented: compatible with poling requirements, manufacturability and reliability. In this work, we demonstrate that a thermosonic bonding process can provide a reliable, metallurgical bond at moderate temperatures, even down to room temperature, with bonding times in the order of seconds. Bonding parameters (temperature, compression force, ultrasonic energy) were optimized by evaluating shear strength on Au stud bump bonded Si chips. Model systems have been bonded, mimicking a complete Electro-Acoustic Module (EAM), including a stack of IC emulator / flex interconnection / interface part of the ultrasound transducer.

Rate of Porous Ni Plaque Corrosion in Ni ( NO 3 ) 2 Solutions

Etude, par des mesures de perte de masse, de la vitesse de corrosion des plaques de nickel poreuses dans des solutions de differentes concentrations en Ni(NO 3 ) 2 utilisees dans le procede de fabrication pour la production de Ni(OH) 2 et NH 3 . Influence de la temperature et de la concentration