A NEW CALCULATING METHOD FOR RELATIVE PERMEABILITY OF BRANCHED PREFORMED PARTICLE GEL FLOODING IN MULTIPHASE COMPOSITE SYSTEM

A new approach for the CTE on the basis of Ashelby.s cutting and welding process was made for the analysis of the thermal expansion behaviors of Al-Si alloys and composites. In this theoretical approach, it was considered that relaxation of residual stress could create an elastoplastic zone in the matrix around a particle during cooling. A comparison of the measured CTEs with the calculated ones for the Al-Si-SiCp and Al-Si-Al2O3 composite systems was performed in terms of the volume percent and the size of reinforced phases. The calculated results revealed that the linear CTE of the both composite depends on the size of the reinforce phases, especially at the composite systems with a low volume percent of the reinforce phases. The increase in the volume percentages of Al2O3, SiCp and Si phase lowers the linear CTEs of the systems. The measured CTEs was deviated less than about ten percents from the calculated ones at composites with a high volume percent. The deviations of the CTEs of reinforced phases are about 4 - 6 vol% from real composite systems.

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Cancellation Effect in Three-Phases TiO2/(PVDF+Fe3O4) Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.463-464.431 ◽

2012 ◽

Vol 463-464 ◽

pp. 431-434 ◽

Cited By ~ 2

Author(s):

Hong Qiang Shan ◽

Xin Ming Wang ◽

Wei Ping Li

Keyword(s):

Dielectric Constant ◽

Synergistic Effect ◽

Composite System ◽

High Dielectric Constant ◽

Relative Dielectric Constant ◽

Dielectric Measurement ◽

Low Loss ◽

Measurement Results ◽

High Dielectric ◽

Multiphase Composite

In order to obtain the high dielectric constant and low loss materials by using the two main methods for synergy, the 3-phases TiO2/(PVDF+Fe3O4) composites with the fixed Fe3O4 fraction have been prepared by using a simple blending and hot-molding technique. The dielectric measurement results show that no synergistic effect but a cancellation effect has been found here, corresponding to the decrease of dielectric constant and conductivity. The value of the relative dielectric constant dropped to the original level of polymer matrix. The reasons for the counter result are present here. It is helpful and reference for the proper choice for multiphase composite system.

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Mathematical Model of Transmission Mechanism from Multiphase Composite System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.850-851.300 ◽

2013 ◽

Vol 850-851 ◽

pp. 300-303

Author(s):

Guan Min Li

Keyword(s):

Mathematical Model ◽

Ionic Conductivity ◽

Polymer Electrolytes ◽

Conduction Mechanism ◽

Composite System ◽

Effective Medium Theory ◽

Transmission Mechanism ◽

Medium Theory ◽

Ion Conduction Mechanism ◽

Multiphase Composite

As part of the weak electrolyte, Multiphase Composite System’s structure is more complex. So the conductive electrolyte ion transport has some difficulty to understanding the mechanism. And the present study has not yet reached a consensus, but through the ion conduction mechanism in-depth research on polymer electrolytes Preparation of important guiding significance. Current theories include ionic conductivity effective medium theory (EMT), MN law, WFL equation, NE equation, dynamic bonding penetration model.

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Processing and characterization of YBa2Cu3O7−x/Ag composites

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100173364 ◽

1990 ◽

Vol 48 (4) ◽

pp. 46-47

Author(s):

Jafar Javadpour ◽

Bradley L. Thiel ◽

Sarikaya Mehmet ◽

Ilhan A. Aksay

Keyword(s):

Composite System ◽

Precursor Solution ◽

Microstructural Development ◽

Superconducting Properties ◽

Practical Applications ◽

Nitrate Precursor ◽

Cold Pressed ◽

Tape Cast ◽

Composite Samples

Practical applications of bulk YBa2Cu3O7−x materials have been limited because of their inadequate critical current density (jc) and poor mechanical properties. Several recent reports have indicated that the addition of Ag to the YBa2Cu3O7−x system is beneficial in improving both mechanical and superconducting properties. However, detailed studies concerning the effect of Ag on the microstructural development of the cermet system have been lacking. Here, we present some observations on the microstructural evolution in the YBa2Cu3O7−x/Ag composite system.The composite samples were prepared by mixing various amounts (2.5 - 50 wt%) AgNO3 in the YBa2Cu3O7−x nitrate precursor solution. These solutions were then spray dried and the resulting powders were either cold pressed or tape cast. The microstructures of the sintered samples were analyzed using SEM (Philips 515) and an analytical TEM (Philips 430T).The SEM micrographs of the compacts with 2.5 and 50 wt% Ag addition sintered at 915°C (below the melting point of Ag) for 1 h in air are displayed in Figs. 1 and 2, respectively.

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