The Experts below are selected from a list of 113088 Experts worldwide ranked by ideXlab platform
D.d.l. Chung - One of the best experts on this subject based on the ideXlab platform.
-
A review of multifunctional Polymer-Matrix structural composites
Composites Part B: Engineering, 2019Co-Authors: D.d.l. ChungAbstract:This paper reviews multifunctional structural materials, particularly continuous fiber Polymer-Matrix composites. The non-structural functions include sensing, EMI shielding, heating, energy generation, energy storage, actuation and self-healing. For each function, the materials, composite design, functional performance and relevant technological needs are covered. Both unmodified and modified forms of the composite are addressed. Sensing, EMI shielding, heating and actuation are functions that do not require modification, though modifications can be performed. In contrast, energy generation, energy storage and self-healing require modification. For a continuous fiber Polymer-Matrix composite, the modification commonly involves the incorporation of constituents at the interlaminar interface.
-
Polymer-Matrix composites for microelectronics
Polymers and Polymer Composites, 2000Co-Authors: D.d.l. ChungAbstract:Polymer-Matrix composite materials for microelectronics are reviewed in terms of the science and applications. They include those with continuous and discontinuous fillers in the form of particles and fibres, as designed for high thermal conductivity, low thermal expansion, low dielectric constant, high/low electrical conductivity and electromagnetic interference shielding. Applications include heat sinks, housings, printed wiring boards, substrates, lids, die attach, encapsulation, interconnections and thermal interface materials.
-
electromagnetic interference shielding using continuous carbon fiber carbon Matrix and Polymer Matrix composites
Composites Part B-engineering, 1999Co-Authors: D.d.l. ChungAbstract:A carbon-Matrix composite with continuous carbon-fibers was found to be an excellent electromagnetic interference (EMI) shielding material with shielding effectiveness 124 dB, low surface impedance and high reflectivity in the frequency range from 0.3 MHz to 1.5 GHz. The shielding effectiveness of Polymer-Matrix composites with continuous carbon-fibers was less and that of Polymer-Matrix composites with discontinuous fillers was even less. The addition of 2.9 vol.% discontinuous 0.1 μm diameter carbon-filaments between the layers of conventional 7 μm diameter continuous carbon-fibers in a composite degraded the shielding effectiveness. The dominant mechanism of EMI shielding for both carbon-Matrix and Polymer-Matrix continuous carbon-fiber composites is reflection.
Georgios C. Psarras - One of the best experts on this subject based on the ideXlab platform.
-
Dielectric behaviour and functionality of Polymer Matrix - ceramic BaTiO3 composites
Express Polymer Letters, 2020Co-Authors: A. Patsidis, Georgios C. PsarrasAbstract:Dielectric properties of Polymer Matrix - ceramic BaTiO3 composites were examined by means of Broadband Dielectric Spectroscopy (BDS) in the frequency range of 10 -1 -10 7 Hz and over the temperature range of 30-160°C, vary- ing the content of ferroelectric particles. Experimental results provide evidence that the recorded relaxation phenomena include contributions from both the Polymeric Matrix and the presence of the reinforcing phase. Obtained results are analysed via the electric modulus formalism. Polymer Matrix exhibits two distinct relaxation processes attributed, with ascending relaxation rate, to glass/rubber transition, and local motions of polar side groups. Interfacial polarization or Maxwell-Wagner-Sillars process is present in the low frequency range and at high temperatures. Finally, in the vicinity of the characteristic Curie temperature (TC) an abrupt variation of the real part of dielectric permittivity with temperature is recorded. This peak is probably related to the ferroelectric to paraelectric phase transition of the employed ceramic inclu- sions.
-
Dielectric behaviour and functionality of Polymer Matrix - ceramic BaTiO3 composites
eXPRESS Polymer Letters, 2008Co-Authors: A. Patsidis, Georgios C. PsarrasAbstract:Dielectric properties of Polymer Matrix - ceramic BaTiO3 composites were examined by means of Broadband Dielectric Spectroscopy (BDS) in the frequency range of 10(-1)-10(7) Hz and over the temperature range of 30-160 degrees C, varying the content of ferroelectric particles. Experimental results provide evidence that the recorded relaxation phenomena include contributions from both the Polymeric Matrix and the presence of the reinforcing phase. Obtained results are analysed via the electric modulus formalism. Polymer Matrix exhibits two distinct relaxation processes attributed, with ascending relaxation rate, to glass/rubber transition, and local motions of polar side groups. Interfacial polarization or Maxwell-Wagner-Sillars process is present in the low frequency range and at high temperatures. Finally, in the vicinity of the characteristic Curie temperature (T-C) an abrupt variation of the real part of dielectric permittivity with temperature is recorded. This peak is probably related to the ferroelectric to paraelectric phase transition of the employed ceramic inclusions.
-
electrical relaxation dynamics in tio2 Polymer Matrix composites
Express Polymer Letters, 2007Co-Authors: G Kontos, Georgios C. Psarras, A Soulintzis, P K Karahaliou, S N Georga, C A Krontiras, M N PisaniasAbstract:Polymer Matrix-TiO2 composites were prepared in three different filler concentrations. The electrical relaxation dynamics as well as the electrical conductivity of all samples were examined by means of Broadband Dielectric Spec- troscopy (BDS) over a wide frequency and temperature range. The recorded relaxation response includes contributions from both the Polymer Matrix and the reinforcing phase. Two relaxation modes (β and γ) are observed in the low tempera- ture region, which are attributed to the re-orientation of polar side groups of the Matrix and rearrangement of small parts of the Polymeric chain respectively. The α-relaxation and the Maxwell-Wagner-Sillars effect (MWS), attributed to the glass- rubber transition of the Polymeric Matrix and to interfacial polarization phenomena respectively, are observed in the high temperature region. These two mechanisms are superimposed, thus a computer simulation procedure was followed in order to distinguish them. MWS effect becomes more pronounced with increasing concentration of the filler following an Arrhe- nius behaviour. The relaxation frequencies corresponding to α-mode follow the Vogel-Tamann-Fulcher (VTF) equation. An additional relaxation mode is recorded at relatively high temperatures and high frequencies. Its occurrence and dynam- ics are related to the presence and the concentration of the filler. Finally, the Direct Current (DC) conductivity follows the VTF equation.
Deborah D.l. Chung - One of the best experts on this subject based on the ideXlab platform.
-
Piezoresistivity in continuous carbon fiber Polymer-Matrix and cement-Matrix composites
Journal of Materials Science, 2000Co-Authors: Sihai Wen, Shoukai Wang, Deborah D.l. ChungAbstract:Piezoresistivity was observed in continuous unidirectional carbon fiber cement-Matrix and Polymer-Matrix composites. The fiber volume fraction was 2.6-7.4% and 58% for cement-Matrix and Polymer-Matrix composites respectively. The DC electrical resistance in the fiber direction increased upon tension in the fiber direction for the cement-Matrix composite, due to fiber-Matrix interface degradation, but decreased upon tension for the Polymer-Matrix composite due to increase in the degree of fiber alignment. (C) 2000 Kluwer Academic Publishers.
-
Electromagnetic interference shielding using continuous carbon-fiber carbon-Matrix and Polymer-Matrix composites
Composites Part B: Engineering, 1999Co-Authors: Xiangcheng Luo, Deborah D.l. ChungAbstract:A carbon-Matrix composite with continuous carbon-fibers was found to be an excellent electromagnetic interference (EMI) shielding material with shielding effectiveness 124 dB, low surface impedance and high reflectivity in the frequency range from 0.3 MHz to 1.5 GHz. The shielding effectiveness of Polymer-Matrix composites with continuous carbon-fibers was less and that of Polymer-Matrix composites with discontinuous fillers was even less. The addition of 2.9 vol.% discontinuous 0.1 ??m diameter carbon-filaments between the layers of conventional 7 ??m diameter continuous carbon-fibers in a composite degraded the shielding effectiveness. The dominant mechanism of EMI for both carbon-Matrix and Polymer-Matrix continuous carbon-fiber composites is reflection.
A. Patsidis - One of the best experts on this subject based on the ideXlab platform.
-
Dielectric behaviour and functionality of Polymer Matrix - ceramic BaTiO3 composites
Express Polymer Letters, 2020Co-Authors: A. Patsidis, Georgios C. PsarrasAbstract:Dielectric properties of Polymer Matrix - ceramic BaTiO3 composites were examined by means of Broadband Dielectric Spectroscopy (BDS) in the frequency range of 10 -1 -10 7 Hz and over the temperature range of 30-160°C, vary- ing the content of ferroelectric particles. Experimental results provide evidence that the recorded relaxation phenomena include contributions from both the Polymeric Matrix and the presence of the reinforcing phase. Obtained results are analysed via the electric modulus formalism. Polymer Matrix exhibits two distinct relaxation processes attributed, with ascending relaxation rate, to glass/rubber transition, and local motions of polar side groups. Interfacial polarization or Maxwell-Wagner-Sillars process is present in the low frequency range and at high temperatures. Finally, in the vicinity of the characteristic Curie temperature (TC) an abrupt variation of the real part of dielectric permittivity with temperature is recorded. This peak is probably related to the ferroelectric to paraelectric phase transition of the employed ceramic inclu- sions.
-
Dielectric behaviour and functionality of Polymer Matrix - ceramic BaTiO3 composites
eXPRESS Polymer Letters, 2008Co-Authors: A. Patsidis, Georgios C. PsarrasAbstract:Dielectric properties of Polymer Matrix - ceramic BaTiO3 composites were examined by means of Broadband Dielectric Spectroscopy (BDS) in the frequency range of 10(-1)-10(7) Hz and over the temperature range of 30-160 degrees C, varying the content of ferroelectric particles. Experimental results provide evidence that the recorded relaxation phenomena include contributions from both the Polymeric Matrix and the presence of the reinforcing phase. Obtained results are analysed via the electric modulus formalism. Polymer Matrix exhibits two distinct relaxation processes attributed, with ascending relaxation rate, to glass/rubber transition, and local motions of polar side groups. Interfacial polarization or Maxwell-Wagner-Sillars process is present in the low frequency range and at high temperatures. Finally, in the vicinity of the characteristic Curie temperature (T-C) an abrupt variation of the real part of dielectric permittivity with temperature is recorded. This peak is probably related to the ferroelectric to paraelectric phase transition of the employed ceramic inclusions.
Jicai Feng - One of the best experts on this subject based on the ideXlab platform.
-
friction stir welding processing of Polymers and Polymer Matrix composites
Composites Part A-applied Science and Manufacturing, 2018Co-Authors: Yongxian Huang, Xiangchen Meng, Zongliang Lv, Jicai FengAbstract:Abstract Friction stir welding/processing (FSW/P) involving temperature, mechanics, metallurgy and interaction, is a complex solid state joining and processing technology. FSW has been widely applied to join aluminum alloy, titanium alloy and other materials which are difficult to weld by fusion welding. The last scientific study states that FSW has potential to join thermoplastic Polymers and Polymer Matrix composites. In this review, current understanding and development about FSW of thermoplastic Polymers and Polymer Matrix composites, multifunctional composites fabrication as well as dissimilar FSW of metal and Polymer are reviewed. Future scientific research and engineering development related to FSW/P of thermoplastic Polymers and Polymer Matrix composites are identified.
-
Friction stir welding/processing of Polymers and Polymer Matrix composites
Composites Part A-applied Science and Manufacturing, 2018Co-Authors: Yongxian Huang, Xiangchen Meng, Zongliang Lv, Jicai FengAbstract:Abstract Friction stir welding/processing (FSW/P) involving temperature, mechanics, metallurgy and interaction, is a complex solid state joining and processing technology. FSW has been widely applied to join aluminum alloy, titanium alloy and other materials which are difficult to weld by fusion welding. The last scientific study states that FSW has potential to join thermoplastic Polymers and Polymer Matrix composites. In this review, current understanding and development about FSW of thermoplastic Polymers and Polymer Matrix composites, multifunctional composites fabrication as well as dissimilar FSW of metal and Polymer are reviewed. Future scientific research and engineering development related to FSW/P of thermoplastic Polymers and Polymer Matrix composites are identified.