United States of America As Represented by the Secretary of the Air Force

Other

The United States of America As Represented by the Secretary of

Cornell Research Foundation Inc.

Alexander N Pechenik

Wesley P Hoffman

Phillip G Wapner

Hector D Abruna

Gasper J Piermarini

Jamie Lee Cohen

David James Volpe

Daron A Westly

Provided are methods to fabricate bulk quantities at relatively low-cost of isotropic homogeneous nanostructured materials with high interfacial area whose properties are controlled and optimized by tailored interfaces between discrete dissimilar materials. In a preferred embodiment, the material is formed by uniformly and intimately mixing nanoparticles of different composition and then compacting and consolidating them to near theoretical density by a process that minimizes grain growth and controls the structure of the interfacial film-like region. One preferred application of these materials is a fast ion conducting material that can be used as a solid electrolyte in gas electrolyzers, electrochemical pumps, gas sensors, catalytic reactors, and most importantly in fuel cells.

Tailored interfaces between two dissimilar nano-materials and method of manufacture

This present invention describes interface-defined nanolaminates (IDnLs), which are novel nanolaminate materials fabricated from metals and ceramics, and new methods for fabricating these IDnL materials, including new methods for manufacturing high aspect ratio parts comprising IDnL materials according to the present invention. IDnLs are fundamentally different from ordinary laminates in that their properties are defined by the interfaces between the layers rather by the properties of the bulk materials comprising the individual layers. In contrast to superlattice materials, IDnLs may be made thermally stable due to the wide selection of interface-defining materials, which allows judicial use of equilibrium phase diagrams. The degree of interface coherency in IDnLs may be varied to optimize material properties. In addition, IDnLs may be manufactured inexpensively in bulk, industrial quantities and large sizes by the techniques disclosed in this invention.

Methods for fabrication of parts from bulk low-cost interface-defined nanolaminated materials

This invention describes a novel type of materials named by the inventors as Interface-Defined nano-Laminates (IDnL), and a new method for fabricating these materials from ceramic, metallic, and other powders. The laminate layer thickness in IDnL is smaller than that of ordinary laminates, but greater than that of superlattices. IDnL are fundamentally different from ordinary laminates in that their properties are defined by interfaces, and not by the properties of the bulk materials comprising individual layers. In contrast to superlattice materials, IDnL can be made thermally stable, due to the wide selection of interface-defining materials, which allows judicial use of equilibrium phase diagrams, and the 'entropic stabilization' approach discovered by the authors; and in addition IDnL can be manufactured inexpensively in bulk, industrial quantities and large sizes by the techniques revealed in this invention. The degree of interface coherency in an IDnLs can be varied to optimize material properties.

Bulk low-cost interface-defined laminated materials and their method of fabrication

This invention describes a unique of class of nano-scale materials for use as protective coatings or barriers against heat as well as material loss due to processes such as corrosion, ablation, erosion, or oxidation. These nano-scale laminated materials are also useful as free-standing components and as substrates, especially for high temperature oxidation-resistant applications. The novel materials of this invention are known as interface-defined nano-laminates (IDnLs), and are fabricated by a new method from ceramic, metallic, and other powders. The laminate layer thickness in an IDnL is smaller than that of ordinary laminates but greater than that of superlattices. Interface-defined nano-laminates are fundamentally different from ordinary laminates in that their properties are defined by interfaces, and not by the properties of the bulk materials comprising individual layers.

Bulk low cost interface-defined laminated metallic and ceramic energy barrier materials and their method of fabrication

A planar microfluidic membraneless flow cell. The design eliminates the need for a mechanical membrane, such as a polyelectrolyte membrane (PEM) in a fuel cell, by providing a flow channel in which laminar flow regimes exist in two fluids flowing in mutual contact to form a 'virtual interface' in the flow channel. In the flow cell, diffusion at the interface is the only mode of mass transport between the two fluids. In a fuel cell embodiment, a planar design provides to large contact areas between the two streams, which are fuel and oxidant streams, and between each stream and a respective electrode. In some embodiments, silicon microchannels, of fixed length and variable width and height, have been used to generate power using formic acid as fuel and oxygen as oxidant. Power densities on the order of 180 &#x3bc;W/cmhave been obtained using this planar design.

Planar membraneless microchannel fuel cell

There are provided methods for fabricating baby bottle nipples which mimic the function of the human breast nipple. In the human breast nipple, milk is delivered to the baby through 15-25 fluid-delivery capillaries called lactiferous ducts. These ducts are 2-4 centimeters in length and 500-900 microns in diameter. Baby bottle nipples fabricated in accordance with the methods of this invention have the common feature of at least one hydrophilic fluid delivery passage. In one embodiment, the fluid delivery passage is a microtube. In another embodiment, the fluid delivery passage is a microchannel. In yet another embodiment, the fluid delivery passage comprises a porous reticulated foam with interconnected pores. In each of these embodiments, the fluid delivery passage has at least one dimension in the range of 1-2000 microns.

Method of manufacture of baby-feeding nipple

Baby bottle nipples which mimic the function of the human breast nipple are provided. In the human breast nipple, milk is delivered to the baby through 15-25 fluid-delivery capillaries called lactiferous ducts. These ducts are 2-4 centimeters in length and 500-900 microns in diameter. Baby bottle nipples fabricated in accordance with the methods of this invention have the common feature of at least one hydrophilic fluid delivery passage. In one embodiment, the fluid delivery passage is a microtube. In another embodiment, the fluid delivery passage is a microchannel. In yet another embodiment, the fluid delivery passage comprises a porous reticulated foam with interconnected pores. In each of these embodiments, the fluid delivery passage has at least one dimension in the range of 1-2000 microns.

Baby-feeding nipple

The stamping process and a method of fabrication of nano-stamps with characteristic dimensions below 1 nm and up to 100 nm intended for usage in making patterns of characteristic dimensions the same as those of the nano-stamp on surface of a substrate is provided. In the process a very hard stamp is fabricated by first depositing alternating layers of two materials, one of which has very high hardness, on some sacrificial substrate via PVD, CVD or any other deposition procedure that produces alternating layers of selected thickness, from sub 1 nm to above 100 nm. The layered film is then polished to an atomically smooth finish perpendicular to the plane of the layers and etched to produce dips in the softer layers. These steps produce a grid of parallel elevations and valleys on the etched surface, which now can be used as a stamp to stamp out patterns on a substrate of lower hardness than the hardness of the elevated layers. If the substrate is stamped twice with a turning of the stamp 90 degrees between first and second stampings, a square pattern of elevations or hills and valleys is formed, which can be used for magnetic memory storage by subsequently sputtering magnetic material on the tops of the elevations or hills.

Method for making a nano-stamp and for forming, with the stamp, nano-size elements on a substrate

A method of producing a dense compact of ultra-fine powder employs low temperatures and high pressures to produce a very dense, nearly ideally packed compact from a starting nano-sized powder. The final product is capable of being easily hot-pressed or sintered to full density.

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Getzville, NY, United States of America

Alexander N Pechenik