Barium titanate/noble metal laminates prepared by the oxidation of solid metallic precursors

A novel and attractive method for preparing multicomponent electronic ceramics and ceramic-metal composites is the oxidation of solid metallic precursors (SMP). This metallurgical processing route consists of the following steps: (i) preparation of a solid metallic precursor containing the proper ratio of elements for the final ceramic or ceramic-metal composite, (ii) compaction and forming of the metallic precursor into a desired shape, and (iii) oxidation to produce a monolithic ceramic or ceramic-metal composite. While the SMP method has been used to prepare wires and tapes containing a variety of superconducting oxides, this method has not been widely used to synthesize other electronic ceramics. In this paper, the synthesis of dielectric BaTiO3/noble metal laminates from solid metallic precursors is discussed. Ba–Ti precursor powders have been produced by solid-state mechanical alloying. The precursor powder was sealed inside noble metal tubes and rolled to form thin Ba–Ti/noble metal laminates. Exposure of the Ba–Ti core in such tapes to temperatures ≥ 300 °C in pure oxygen resulted in rapid oxidation. Post-oxidation annealing at elevated temperatures (≥900 °C) yielded dielectric BaTiO3/Ag or BaTiO3/Pd laminates.

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Synthesis of Superconducting Oxides and Oxide/Metal Composites by Oxidation of Metallic Precursors

MRS Proceedings ◽

10.1557/proc-99-619 ◽

1987 ◽

Vol 99 ◽

Cited By ~ 4

Author(s):

Gregory J. Yurek ◽

John B. Vander Sande ◽

David A. Rudman

Keyword(s):

Mechanical Properties ◽

High Temperature Oxidation ◽

Elevated Temperatures ◽

Metal Composite ◽

Two Phase ◽

Metal Composites ◽

Temperature Oxidation ◽

Metallic Precursor ◽

Cu Alloys ◽

Superconducting Oxides

ABSTRACTOne method for the synthesis of superconducting oxides is high temperature oxidation of a metallic alloy (a metallic precursor) that contains the metallic constituents of the oxide. In addition, a noble metal can be added to the precursor such that, after oxidation, a two phase, finely divided oxide/metal composite results. Superconducting oxides have been produced from Eu-Ba-Cu and Yb-Ba-Cu alloys by oxidizing the alloys at 300°C followed by an “oxygen anneal” at elevated temperatures. Similarly, a Eu1,Ba2Cu3O7−x /Au composite has been formed from a quaternary metallic precursor. each case an onset of superconductivity occurred at about 92K. This approach to producing superconducting oxides is felt to have a number of advantages associated with it, not the least of which is the improvement of the mechanical properties of the superconducting product.

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Biomimetic Applications of Ionic Polymer Metal Composites (IPMC) Actuators - A Critical Review

Journal of Biomimetics Biomaterials and Biomedical Engineering ◽

10.4028/www.scientific.net/jbbbe.20.1 ◽

2014 ◽

Vol 20 ◽

pp. 1-10 ◽

Cited By ~ 12

Author(s):

Muhammad Farid ◽

Zhao Gang ◽

Tran Linh Khuong ◽

Zhuang Zhi Sun ◽

Naveed Ur Rehman ◽

...

Keyword(s):

Critical Review ◽

Low Voltage ◽

Metal Composite ◽

Ionic Polymer Metal Composite ◽

Metal Composites ◽

Ionic Polymer Metal Composites ◽

Ionic Polymer ◽

Design And Manufacturing ◽

Polymer Metal ◽

Biomedical Field

Biomimetic is the field of engineering in which biological creatures and their functions are investigated and are used as the basis for the design and manufacturing of machines. Ionic Polymer Metal Composite (IPMC) is a smart material which has demonstrated a meaningful bending and tip force after the application of a low voltage. It is light-weighted, flexible, easily actuated, multi-directional applicable and requires simple manufacturing. Resultantly, IPMC has attracted scientists and researchers to analyze it further and consider it for any industrial and biomimetic applications. Presently, the research on IPMC is bi-directional oriented. A few groups of researchers are busy to find out the causes for the weaknesses of the material and to find out any remedy for them. The second class of scientists is exploring new areas of applications where IPMC material can be used. Although, the application zone of IPMC is ranging from micropumps diaphragms to surgical holding devices, this paper provides an overview of the IPMC application in biomimetic and biomedical field.

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Enhanced Performance of SnO₂-Noble Metal Composites on Electrical Energy Generation and Storage Devices

IEEE Transactions on Electron Devices ◽

10.1109/ted.2021.3107224 ◽

2021 ◽

pp. 1-7

Author(s):

S. Amuthameena ◽

K. Dhayalini ◽

B. Balraj ◽

C. Siva

Keyword(s):

Noble Metal ◽

Electrical Energy ◽

Energy Generation ◽

Metal Composites ◽

Storage Devices ◽

And Storage ◽

Electrical Energy Generation

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YBa2Cu3O7/noble metal composite thin films for applications in fluxonic and flux-flow devices

Applied Superconductivity ◽

10.1016/0964-1807(96)00003-8 ◽

1995 ◽

Vol 3 (11-12) ◽

pp. 607-614 ◽

Cited By ~ 6

Author(s):

Michael A. Fisher ◽

Laura H. Allen ◽

Edward J. Cukauskas

Keyword(s):

Thin Films ◽

Noble Metal ◽

Metal Composite ◽

Composite Thin Films ◽

Flux Flow ◽

Flow Devices

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Composite Sandwich with Aluminum Foam Core and Adhesive Bonded Carbon Fiber Reinforced Thermoplastic Cover Layer

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.744.277 ◽

2017 ◽

Vol 744 ◽

pp. 277-281 ◽

Cited By ~ 1

Author(s):

Alexander Hackert ◽

Claudia Drebenstedt ◽

Tristan Timmel ◽

Tomasz Osiecki ◽

Lothar Kroll

Keyword(s):

Mechanical Properties ◽

Aluminum Foam ◽

New Technologies ◽

Bending Stiffness ◽

Metal Composite ◽

Fiber Reinforced ◽

Metal Composites ◽

Reinforced Plastics ◽

Composite Sandwich ◽

Fiber Reinforced Plastics

The combination of metals and fiber reinforced plastics is also known as hybrid metal composites. They offer the fusion of the good static mechanical properties of the fiber reinforced plastics and the good dynamic mechanical properties of the metal. For that reason, parts made of hybrid metal composites are predestined for the use as load relevant parts. The purpose of this study was to develop new technologies for semi finished hybrid metal composite materials. Thermoplastic Fiber-Reinforced Composites (TP-FRC) were arranged with new, isotropic, closed pore Aluminum Foam (AF) structures to an Extrinsically Combined Composite Sandwich (ECCS) by adhesive bonding. They form the basis for novel weight-optimized as well as cost-effective applications. The entire manufacturing process for the continuous semi-finished product was examined and verified according DIN EN 2563. This was done with regard to subsequent characterization by the specific bending modulus and specific bending stiffness. The examinations show a high bending stiffness and high strength structures combined with excellent damping properties at high damage tolerances. These are the most requested in automotive applications.

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Noble Metal Composite Porous Silk Fibroin Aerogel Fibers

Materials ◽

10.3390/ma12060894 ◽

2019 ◽

Vol 12 (6) ◽

pp. 894 ◽

Cited By ~ 4

Author(s):

Alexander Mitropoulos ◽

F. Burpo ◽

Chi Nguyen ◽

Enoch Nagelli ◽

Madeline Ryu ◽

...

Keyword(s):

Noble Metal ◽

Silk Fibroin ◽

Noble Metals ◽

Metal Salt ◽

Supercritical Drying ◽

Noble Metal Nanoparticles ◽

Metal Composite ◽

Composite Aerogel ◽

Wide Range ◽

Composite Aerogels

Nobel metal composite aerogel fibers made from flexible and porous biopolymers offer a wide range of applications, such as in catalysis and sensing, by functionalizing the nanostructure. However, producing these composite aerogels in a defined shape is challenging for many protein-based biopolymers, especially ones that are not fibrous proteins. Here, we present the synthesis of silk fibroin composite aerogel fibers up to 2 cm in length and a diameter of ~300 μm decorated with noble metal nanoparticles. Lyophilized silk fibroin dissolved in hexafluoro-2-propanol (HFIP) was cast in silicon tubes and physically crosslinked with ethanol to produce porous silk gels. Composite silk aerogel fibers with noble metals were created by equilibrating the gels in noble metal salt solutions reduced with sodium borohydride, followed by supercritical drying. These porous aerogel fibers provide a platform for incorporating noble metals into silk fibroin materials, while also providing a new method to produce porous silk fibers. Noble metal silk aerogel fibers can be used for biological sensing and energy storage applications.

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Formation of Fe3AlC Base Alloy by Mechanical Alloying and Vacuum Hot Pressing

Materials Science Forum ◽

10.4028/www.scientific.net/msf.534-536.189 ◽

2007 ◽

Vol 534-536 ◽

pp. 189-192 ◽

Cited By ~ 2

Author(s):

Kazuo Isonishi

Keyword(s):

Mechanical Alloying ◽

Hot Pressing ◽

Base Alloy ◽

Average Particle Size ◽

Processing Route ◽

Full Density ◽

Second Phase ◽

Average Particle ◽

Vacuum Hot Pressing ◽

Metallurgical Processing

Fabrication of Fe3AlC matrix in-situ composite, reinforced by a FeAl phase, was studied by using the powder metallurgical processing route. Especially, in order to disperse the second phase more finely, we chose the mechanical alloying process. We investigated the microstructural and mechanical properties of the consolidated material. After consolidation by vacuum hot pressing, the compact showed almost full density and consisted of a Fe3AlC matrix and FeAl second phase (average particle size was less than 1μm). The compact showed HV746, which was higher than that of the arc melted Fe3AlC monolithic material, HV650.

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Modeling Ionic Polymer-Metal Composites with Space-Time Adaptive Multimeshhp-FEM

Communications in Computational Physics ◽

10.4208/cicp.081110.180311a ◽

2012 ◽

Vol 11 (1) ◽

pp. 249-270 ◽

Cited By ~ 9

Author(s):

David Pugal ◽

Pavel Solin ◽

Kwang J. Kim ◽

Alvo Aabloo

Keyword(s):

Coupled System ◽

Metal Composite ◽

Ionic Polymer Metal Composite ◽

The Finite Element Method ◽

Metal Composites ◽

Ionic Polymer Metal Composites ◽

Ionic Polymer ◽

Qualitative And Quantitative ◽

Polymer Metal ◽

Adaptive Fem

AbstractWe are concerned with a model of ionic polymer-metal composite (IPMC) materials that consists of a coupled system of the Poisson and Nernst-Planck equations, discretized by means of the finite element method (FEM). We show that due to the transient character of the problem it is efficient to use adaptive algorithms that are capable of changing the mesh dynamically in time. We also show that due to large qualitative and quantitative differences between the two solution components, it is efficient to approximate them on different meshes using a novel adaptive multimeshhp-FEM. The study is accompanied with numerous computations and comparisons of the adaptive multimeshhp-FEM with several other adaptive FEM algorithms.

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Lower and Upper Bounds of Mechanical and Thermal Properties of Ceramic/Metal Composites

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.336-338.2440 ◽

2007 ◽

Vol 336-338 ◽

pp. 2440-2443 ◽

Cited By ~ 1

Author(s):

Jin Sheng Xiao ◽

Zhi Gang Zhan ◽

Wen Hua Zhao ◽

Wei Biao Fu

Keyword(s):

Heat Flux ◽

Temperature Difference ◽

Poisson Ratio ◽

Effective Strain ◽

Property Values ◽

Upper Bounds ◽

Mechanical And Thermal Properties ◽

Metal Composite ◽

Lower And Upper Bounds ◽

Metal Composites

In this paper, the lower and upper bounds of Young’s modulus and Poisson ratio are determined by the effective stress method and effective strain method from material mechanics. The effective heat flux method based on the hypothesis of equivalent temperature difference and the effective temperature difference method based on the hypothesis of equivalent heat flux are proposed, the lower and upper bounds of the thermal conductivity of ceramic/metal composite material are determined similarly. The result shows that the property values of ceramic/metal composites calculated from current theoretical property formulas are within the lower and upper bounds determined by the above methods.

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