Los Alamos National Security, LLC

University of California

The United States of America As Represented by the Department of Energy

Yuntian Theodore Zhu

Paul N Arendt

Dean E Peterson

Terry C Lowe

Quanxi Jia

Igor Olegovich Usov

Huisheng Peng

Qingwen Li

Ruslan Zufarovich Valiev

Georgy J Raab

Xiefei Zhang

Terry G Holesinger

John F Bingert

Lei Fu

Ramond F DePaula

Adriana C Serquis

Frederick M Mueller

Xiao Zhou Liao

Vladimir V Stolyarov

Vladimir V Latysh

Lianxi Zheng

Patrick S Baldonado

Honggang Jiang

Jianyu Huang

Yonghao Zhao

Xiefie Zhang

A spun fiber of carbon nanotubes is exposed to ion irradiation. The irradiation exposure increases the specific strength of the spun fiber.

Increasing the specific strength of spun carbon nanotube fibers

A structure for preparing an substantially aligned array of carbon nanotubes include a substrate having a first side and a second side, a buffer layer on the first side of the substrate, a catalyst on the buffer layer, and a plurality of channels through the structure for allowing a gaseous carbon source to enter the substrate at the second side and flow through the structure to the catalyst. After preparing the array, a fiber of carbon nanotubes may be spun from the array. Prior to spinning, the array can be immersed in a polymer solution. After spinning, the polymer can be cured.

Preparation of arrays of long carbon nanotubes using catalyst structure

An array of carbon nanotubes is prepared by exposing a catalyst structure to a carbon nanotube precursor. Embodiment catalyst structures include one or more trenches, channels, or a combination of trenches and channels. A system for preparing the array includes a heated surface for heating the catalyst structure and a cooling portion that cools gas above the catalyst structure. The system heats the catalyst structure so that the interaction between the precursor and the catalyst structure results in the formation of an array of carbon nanotubes on the catalyst structure, and cools the gas near the catalyst structure and also cools any carbon nanotubes that form on the catalyst structure to prevent or at least minimize the formation of amorphous carbon. Arrays thus formed may be used for spinning fibers of carbon nanotubes.

Preparation of array of long carbon nanotubes and fibers therefrom

A fiber of carbon nanotubes was prepared by a wet-spinning method involving drawing carbon nanotubes away from a substantially aligned, supported array of carbon nanotubes to form a ribbon, wetting the ribbon with a liquid, and spinning a fiber from the wetted ribbon. The liquid can be a polymer solution and after forming the fiber, the polymer can be cured. The resulting fiber has a higher tensile strength and higher conductivity compared to dry-spun fibers and to wet-spun fibers prepared by other methods.

Carbon nanotube fiber spun from wetted ribbon

Fibrous composite comprising a plurality of carbon nanotubes; and a silica-containing moiety having one of the structures: (SiO)Si&#x2014;(CH)&#x2014;NRR) or (SiO)Si&#x2014;(CH)&#x2014;NCO; where n is from 1 to 6, and Rand Rare each independently H, CH, or CH.

Fibrous composites comprising carbon nanotubes and silica

A carbon microtube comprising a hollow, substantially tubular structure having a porous wall, wherein the microtube has a diameter of from about 10 &#x3bc;m to about 150 &#x3bc;m, and a density of less than 20 mg/cm. Also described is a carbon microtube, having a diameter of at least 10 &#x3bc;m and comprising a hollow, substantially tubular structure having a porous wall, wherein the porous wall comprises a plurality of voids, said voids substantially parallel to the length of the microtube, and defined by an inner surface, an outer surface, and a shared surface separating two adjacent voids.

Carbon microtubes

A method for preparing a nanostructured aluminum alloy involves heating an aluminum alloy workpiece at temperature sufficient to produce a single phase coarse grained aluminum alloy, then refining the grain size of the workpiece at a temperature at or below room temperature, and then aging the workpiece to precipitate second phase particles in the nanosized grains of the workpiece that increase the ductility without decreasing the strength of the workpiece.

Preparation of nanostructured materials having improved ductility

An apparatus that continuously processes a metal workpiece without substantially altering its cross section includes a wheel member having an endless circumferential groove, and a stationary constraint die that surrounds the wheel member, covers most of the length of the groove, and forms a passageway with the groove. The passageway has a rectangular shaped cross section. An abutment member projects from the die into the groove and blocks one end of the passageway. The wheel member rotates relative to the die in the direction toward the abutment member. An output channel in the die adjacent the abutment member has substantially the same cross section as the passageway. A metal workpiece is fed through an input channel into the passageway and carried in the groove by frictional drag in the direction towards the abutment member, and is extruded through the output channel without any substantial change in cross section.

Continuous equal channel angular pressing

A process of preparing superconducting magnesium diboride powder by heating an admixture of solid magnesium and amorphous boron powder or pellet under an inert atmosphere in a Mg:B ratio of greater than about 0.6:1 at temperatures and for time sufficient to form said superconducting magnesium diboride. The process can further include exposure to residual oxygen at high synthesis temperatures followed by slow cooling. In the cooling process oxygen atoms dissolved into MgB segregated to form nanometer-sized coherent Mg(B,O) precipitates in the MgB matrix, which can act as flux pinning centers.

Synthesis of magnesium diboride by magnesium vapor infiltration process (MVIP)

We disclose ultrafine-grained titanium. A coarse-grained titanium billet is subjected to multiple extrusions through a preheated equal channel angular extrusion (ECAE) die, with billet rotation between subsequent extrusions. The resulting billet is cold processed by cold rolling and/or cold extrusion, with optional annealing. The resulting ultrafine-grained titanium has greatly improved mechanical properties and is used to make medical implants.

Ultrafine-grained titanium for medical implants

Superconductor tapes are annealed under uniaxial pressure, such a compressive annealing yielding significant improvement in the resultant critical current density. This thermomechanical processing technique obtains improved critical currents with fewer processing steps.

Compressive annealing of superconductive tapes

A method of refining the grain structure and improving the hardness and strength properties of a metal or metal alloy workpiece is disclosed. The workpiece is subjected to forces that corrugate and then straighten the workpiece. These steps are repeated until an ultrafine-grained product having improved hardness and strength is produced.

Growing community of inventors

Cary, NC, United States of America

Yuntian Theodore Zhu