Low-density interconnected metal foams and methods of manufacture

Inactive Publication Date: 2018-11-01
NAT TECH & ENG SOLUTIONS OF SANDIA LLC +2
View PDF4 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

[0019]In one embodiment, the nanowires are formed with a template and electrodeposition. The characteristics of the nanowires are determined by the configuration of the template. The electrodeposition process allows the synthesis of a wide

Problems solved by technology

Although a number of methods for preparing pure metal nanoparticles exist, there are relatively few synthetic processes for producing bulk, monolithic forms of nanostructured metals that have been developed.
Conventional methodologies for fabricating monolithic metallic nanoporous materials or foams have limited practical applications and are difficult to adapt to large scale production because of their complicated procedures and use of expensive materials.
Although selective dealloying approaches have been eff

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Low-density interconnected metal foams and methods of manufacture
  • Low-density interconnected metal foams and methods of manufacture
  • Low-density interconnected metal foams and methods of manufacture

Examples

Experimental program
Comparison scheme
Effect test

Example

Example 1

[0068]In order to demonstrate the operational principles of the fabrication methods, several metal foams were prepared using the fabrication method shown schematically in FIG. 2. In this example, pure metal nanowire foams of Cu, Pd, Co and Ag were fabricated with a wide range of tunable densities.

[0069]Nanowires were grown by electrodeposition into nanoporous templates of various sizes and types, including anodized aluminum oxide (AAO) membranes and polycarbonate membranes, to lengths of between 5 μm and 40 μm and diameters from about 50 nm to 200 nm.

[0070]Magnetron sputtering was used to coat thick conductive layers (200 nm to 500 nm) on the backsides of the membranes for use as working electrodes. For copper and cobalt nanowires, a 500 nm thick copper layer was coated onto the backside of the membrane to cover the template pores and to be used as a working electrode during electrodeposition. For silver, palladium, gold and platinum nanowires, a 500 nm gold working electro...

Example

Example 2

[0079]Nanoindentation experiments were carried out on the foams produced with the methods shown in Example 1 to quantify the enhanced strength of the interconnected Cu nanowire foams. In order to perform nanoindentation measurements, cylindrical Cu foams with a 2 mm height and diameter were fabricated and strengthened using the oxidation / reduction process. The final foams ranged in densities from 8 mg / cm3 to 70 mg / cm3. The indenter tip was a 2 mm ruby sphere and measurements were conducted at room temperature and ambient laboratory humidity. The loading and unloading rate was kept constant at 100 μm / m. A sample loading / unloading curve is shown in FIG. 3.

[0080]Loading / unloading curves were derived for a 9 mg / cm3 strengthened Cu cylindrical foam with 2 mm in height and diameter. By measuring the initial slope of the unloading curve it was possible to extract the modulus of the subject material. The elastic modulus of each sample was extracted from the initial slope of the unl...

Example

Example 3

[0085]One potential use of ultralow density metal foams is for use as high energy density laser targets due to their ability to be heated volumetrically that allows targets composed of high-Z elements to uniformly reach the extreme temperatures that are required for X-ray emission. Gas targets, oxides, metal-doped aerogels and metal-lined cavities have been employed previously for reaching the necessary effective density. However, the pure metal targets allow higher X-ray conversion efficiencies if the targets can be fabricated at densities low enough to allow volumetric heating while still maintaining mechanical stability.

[0086]To demonstrate the functionality of pure metal foam targets produced by the methods, spherical Cu targets (2 mm and 4 mm diameters) and cylindrical Ag targets (4 mm diameter and length) were produced to be used as targets for testing at the OMEGA and the National Ignition Facility (NIF) laser facilities. The enhanced mechanical strength was critical...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
Fractionaaaaaaaaaa
Densityaaaaaaaaaa
Temperatureaaaaaaaaaa
Login to view more

Abstract

Ultralow density pure metal foams, with density approaching 0.1% of the bulk density, and synthesis methods using interconnected metallic nanowires are provided. Nanowires of various sizes and metals are synthesized by electrodeposition into nanoporous templates such as anodized aluminum oxide or polycarbonate. The templates are etched away and the nanowires are dispersed into water through a suitable fluid exchange. Surface treatments ensure that nanowires remain sufficiently metallic and physically separated. Wire-water solutions can be dropped directly into liquid nitrogen in the form of droplets or placed into molds of various shapes. A freeze drying technique is employed to turn the resulting ice-wire mixture into a freestanding, low-density foam composed of interlocked nanowires. Finally, sintering or oxidation and reduction treatment of the foam material at elevated temperatures is used to connect the nanowires into an interconnected metallic foam, greatly improving the strength of the structure.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application is a 35 U.S.C. § 111(a) continuation of PCT international application number PCT / US2016 / 064218 filed on Nov. 30, 2016, incorporated herein by reference in its entirety, which claims priority to, and the benefit of, U.S. provisional patent application Ser. No. 62 / 261,211 filed on Nov. 30, 2015, incorporated herein by reference in its entirety. Priority is claimed to each of the foregoing applications.[0002]The above-referenced PCT international application was published as PCT International Publication No. WO 2017 / 095925 on Jun. 8, 2017, which publication is incorporated herein by reference in its entirety.STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT[0003]This invention was made with Government support under BRCALL08-Per3-C-2-0006, awarded by the Defense Threat Reduction Agency; under DMR-1008791, awarded by the National Science Foundation; and under Contract DE-AC04-94AL85000 between Sandia Corporation ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): B22F3/11B22F1/00C25D1/00C25D1/04
CPCB22F3/1121B22F1/0025C25D1/006C25D1/04B22F2301/255B22F2301/10B22F3/11B22F3/1143B22F1/0547
Inventor BURKS, EDWARD C.GILBERT, DUSTIN A.LIU, KAIKUCHEYEV, SERGEI O.FELTER, THOMAS E.COLVIN, JEFFREY D.
Owner NAT TECH & ENG SOLUTIONS OF SANDIA LLC
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap