Composite Materials Based on Silicone Rubber Used to Mitigation Electromagnetic Pollution

2015 ◽  
Vol 1114 ◽  
pp. 76-80
Author(s):  
Elena Valentina Stoian ◽  
Vasile Bratu ◽  
Florina Violeta Anghelina ◽  
Ileana Nicoleta Popescu
Keyword(s):  
Composite Materials ◽  
Silicone Rubber ◽  
Electromagnetic Waves ◽  
Polymer Matrix Composites ◽  
Raw Materials ◽  
Digital Processing ◽  
Thin Layers ◽  
Matrix Composites ◽  
High Attenuation ◽  
Electromagnetic Pollution

Rapid developments in telecommunications and digital processing of information are facing the problem of electromagnetic wave pollution and interference. The aim of this article is the characterization at microwave frequencies of composite materials based on silicone rubber. These materials contain 80% siloxane rubber and only 20% powdery feeling like nanocarbon and pyrite cinder. To achieve these objectives were reviewed and selected raw materials and characteristics were determined in a structural material, the electromagnetic attenuation as well as electrically, by making measurements of electrical conductivity of thin layers of polymer matrix composites produced by the doctor blade technique. Starting from sample siloxane rubber, i.e. without additives or filler reinforcement in compression analysis we find that reinforcing agents leads to increased values of the modulus of elasticity in especially for pyrite ashes. For materials analyzed in this paper, measurements were made in the frequency range between (1-18) GHz and have found high attenuation over 45 dB in the case of composite materials with pyrite ash filler. So we can say that this materials can used for shielding against electromagnetic waves in order to protect the human factor. The novelty of the paper consists in the compositions of the specimens and their mechanical and electromagnetic characteristics.

scholarly journals Improvement of Microwave Absorbance of Polymer Composites of W-Type Hexaferrite Powders by Attachment of Frequency Selective Surface

2017 ◽  
Vol 62 (2) ◽  
pp. 1325-1328
Author(s):  
H.-S. Cho ◽  
S.-S. Kim
Keyword(s):  
Reflection Loss ◽  
Electromagnetic Waves ◽  
Polymer Matrix Composites ◽  
Magnetic Loss ◽  
Frequency Selective Surface ◽  
Substrate Material ◽  
Matrix Composites ◽  
Frequency Selective ◽  
Ferrite Composites ◽  
Minimum Reflection Loss

AbstractThis work investigates the effect of a frequency selective surface (FSS) composed of a regular array of square loop elements on the absorption properties of grounded ferrite composites. Polymer matrix composites of CoZnW hexaferrite powders having small magnetic loss were used as the substrate material. Computational tools were used to model the interaction between electromagnetic waves and materials and determine the reflection coefficient. Reflection loss and bandwidth were greatly improved by attaching an FSS with controlled electrical resistance (R) onto the grounded ferrite composites. For the FSS withR= 800 Ω, the minimum reflection loss decreased to −25 dB at 10 GHz and the bandwidth was broadened to 7.5-12.5 GHz with respect to −10 dB reflection loss.

Evaluation of the properties of polymer composites with carbon nanotubes in the aspect of their abrasive wear

2019 ◽  
Vol 1 (95) ◽  
pp. 5-12 ◽  
Author(s):  
A. Krzyżak ◽  
E. Kosicka ◽  
R. Szczepaniak ◽  
T. Szymczak
Keyword(s):  
Carbon Nanotubes ◽  
Composite Materials ◽  
Bisphenol A ◽  
Abrasive Wear ◽  
Polymer Composites ◽  
Tribological Properties ◽  
Polymer Matrix Composites ◽  
Matrix Composites ◽  
Friction Modifier ◽  
The Impact

Purpose: Carbon nanotubes are used in composite materials due to the improvement of (including tribological) properties of composites, especially thermoplastic matrix composites. This demonstrates the potential of CNTs and the validity of research on determining the impact of this type of reinforcement on the composite materials under development. Design/methodology/approach: The article presents selected results of research on polymer composites made of C.E.S. R70 resin, C.E.S. H72 hardener with the addition of a physical friction modifier (CNTs) with a percentage by volume of 18.16% and 24.42%, respectively, which also acts as a reinforcement. The produced material was subjected to hardness measurements according to the Shore method and EDS analysis. The study of abrasive wear in reciprocating movement was carried out using the Taber Linear Abraser model 5750 tribotester and a precision weight. The surface topography of the composite material after tribological tests was determined using scanning electron microscopy (SEM). Some of the mentioned tests were carried out on samples made only of resin, used as the matrix of the tested polymer composite. Findings: Carbon nanotubes used in polymer matrix composites, including bisphenol A/F epoxy resin have an influence on the tribological properties of the material. The addition of carbon nanotubes contributed to a 24% increase in the Ra parameter relative to pure resin, to a level corresponding to rough grinding of steel. Research limitations/implications: The results of the tests indicate the need to continue research in order to optimize the composition of composites in terms of operating parameters of friction nodes in broadly understood aviation. Originality/value: The analysed literature did not find any studies on the impact of the addition of carbon nanotubes on epoxy resins based on bisphenol A/F. Due to the wide scope of application of such resins, the properties of such composite materials in which carbon nanotubes are the reinforcing phase have been investigated.

SiOC Composite Structures for Intermediate Service Temperatures with Increased Friction Properties

2014 ◽  
Vol 88 ◽  
pp. 15-20 ◽  
Author(s):  
Rainer Gadow ◽  
Patrick Weichand
Keyword(s):  
Composite Structures ◽  
Polymer Matrix Composites ◽  
Hybrid Composites ◽  
Raw Materials ◽  
Ceramic Matrix Composites ◽  
Thermal Resistivity ◽  
Limiting Factor ◽  
Matrix Composites ◽  
Reinforced Polymers ◽  
Manufacturing Technologies

Polymer Matrix Composites (PMC) are often used in lightweight applications due to their excellent mechanical properties combined with a low density. The manufacturing technologies are fully developed and raw materials are cheap. The limiting factor of these reinforced polymers is the maximum service temperature. Ceramic Matrix Composites (CMC) are suitable for service temperatures up to 1500 °C and more. These composites are composed of ceramic matrices combined with ceramic fibers based on alumina or silicon carbide. This class of composites is handicapped by the high cost of processing and raw materials and therefore only attractive for applications in astronautics and military aviation. Composite materials, bridging the gap between PMC and CMC, are manufactured by the use of polysiloxanes, carbon-and basalt fibers. Such competitive free formable Hybrid-composites are capable for service temperatures up to 800 °C in oxidative atmosphere. In order to make the material attractive also for series applications, manufacturing technologies like filament wet winding, Resin Transfer Moulding (RTM) or pressing techniques are employed. Beside the improved thermal resistivity in comparison to reinforced polymers and light metals, a major benefit of SiOC composites is investigated in the field of friction materials. The excellent properties in wear resistance and an adjustable coefficient of friction make it an interesting alternative for CFC and CMC.

scholarly journals Fatigue tests, self-healing of polymer-matrix composites in unmanned aerial vehicles

2018 ◽  
Vol 48 (1) ◽  
pp. 83-106
Author(s):  
Sławomir Augustyn ◽  
Rafał Kowalski
Keyword(s):  
Composite Materials ◽  
Polymer Matrix Composites ◽  
Stress Test ◽  
Fatigue Tests ◽  
Fiber Reinforced Polymer ◽  
Self Healing ◽  
Matrix Composites ◽  
Four Point Bending ◽  
Reinforced Polymer ◽  
Initial Load

Abstract This publication presented the main issues related to fatigue of polymer composite materials. It was featured a fatigue stress test based on composite sample, made of carbon fiber-reinforced polymer, using the four-point bending method. The test was carried out with the initial load and using positive load cycles. The perspectives of diagnostics and self-healing of composite materials, including intelligent materials, were also presented.

scholarly journals A Review of Prestressed Fibre-Reinforced Polymer Matrix Composites

Polymers ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 60
Author(s):  
Raphael Olabanji Ogunleye ◽  
Sona Rusnakova
Keyword(s):  
Mechanical Properties ◽  
Composite Materials ◽  
Residual Stresses ◽  
Matrix Composite ◽  
Polymer Matrix ◽  
Moisture Absorption ◽  
Polymer Matrix Composites ◽  
Great Influence ◽  
Polymer Matrix Composite ◽  
Matrix Composites

This review examines various studies on reducing tensile stresses generated in a polymer matrix composite without increasing the mass or dimension of the material. The sources of residual stresses and their impacts on the developed composite were identified, and the different techniques used in limiting residual stresses were also discussed. Furthermore, the review elaborates on fibre-prestressing techniques based on elastically (EPPMC) and viscoelastically (VPPMC) prestressed polymer matrix composites, while advantages and limitations associated with EPPMC and VPPMC methods are also explained. The report shows that tensile residual stresses are induced in a polymer matrix composite during production as a result of unequal expansion, moisture absorption and chemical shrinkage; their manifestations have detrimental effects on the mechanical properties of the polymer composite. Both EPPMC and VPPMC have great influence in reducing residual stresses in the polymer matrix and thereby improving the mechanical properties of composite materials. The reports from this study provide some basis for selecting a suitable technique for prestressing as well as measuring residual stresses in composite materials.

scholarly journals Advanced composite materials manufacturing technology

2018 ◽  
Vol 1 (1) ◽  
Author(s):  
Tang Zhijin
Keyword(s):  
Composite Materials ◽  
Metal Matrix Composites ◽  
Metal Matrix ◽  
Polymer Matrix Composites ◽  
Ceramic Matrix Composites ◽  
Matrix Composites ◽  
Preparation Methods ◽  
Advanced Composite ◽  
Advanced Composite Materials ◽  
Preparation Techniques

In recent years, a variety of composite materials preparation technology has been updated, from ceramic matrixcomposites, metal matrix composites to polymer matrix composites, a variety of preparation techniques have beengreatly improved, making the composite properties and applications signifi cantly improved. This paper reviews severalimportant preparation methods and applications of ceramic matrix composites, metal matrix composites and polymermatrix composites.

Development of Aerospace Composite Structures Through Vacuum-Enhanced Resin Transfer Moulding Technology (VERTMTy)

2018 ◽  
pp. 99-111
Author(s):  
Raghu Raja Pandiyan Kuppusamy
Keyword(s):  
Composite Materials ◽  
Composite Structures ◽  
Polymer Matrix Composites ◽  
Wide Spectrum ◽  
Low Cost ◽  
Matrix Composites ◽  
Resin Transfer Moulding ◽  
Advanced Composite ◽  
Advanced Composite Materials ◽  
Transfer Moulding

Quality products with low cost manufacturing routes are the major objectives for the product development in any application. The current statement is evident for polymer-matrix composites, particularly in high end applications such as aerospace and mass transit structures. These applications require advanced composite materials tailored to meet the property demands posted by dynamic load conditions, and hence, the use of wide spectrum of constituents and architectures are vital to cater the needs. Consequently, the development of novel composite materials with the permutations of ingredients leads to the innovative processing techniques. To address the gap in the manufacturing with economical processing routes of thick sectioned advanced composite parts showing superior properties at different wall sections, an innovative composite manufacturing technology coupling resin transfer moulding (RTM) processing and vacuum applications, namely vacuum enhanced resin transfer moulding technology (VERTMTy), is conceptualized, proposed, and developed.

scholarly journals Identifying unified kinetic model parameters for thermal decomposition of polymer matrix composites

2018 ◽  
Vol 53 (20) ◽  
pp. 2875-2890
Author(s):  
Sangwook Sihn ◽  
Gregory J Ehlert ◽  
Ajit K Roy ◽  
Jonathan P Vernon
Keyword(s):  
Composite Materials ◽  
Kinetic Model ◽  
Heating Rate ◽  
Kinetic Models ◽  
Polymer Matrix Composites ◽  
Analysis Data ◽  
Decomposition Kinetics ◽  
Model Parameters ◽  
Matrix Composites ◽  
Heating Rates

Predicting thermal responses of composite materials requires accurate input parameters derived from reliable thermal property characterization and kinetic models. Composite material properties and decomposition kinetics vary with temperature and heating rate. Typically, conventional kinetic models derived from thermogravimetric analysis data result in multiple sets of kinetic model parameters, which are difficult to implement into numerical simulations under widely varying temperature and heating rate conditions. Here, a methodology was developed to reliably predict decomposition processes of composite materials with a single (i.e., unified) set of kinetic model parameters. The unified kinetic model parameters for each of four different composite materials were used to accurately predict decomposition kinetics observed over the entire range of experimental temperatures and heating rates. Furthermore, this broadly applicable methodology may predict decomposition from limited data sets, and is expected to extrapolate reliably measurable data to experimentally challenging heating rates and temperatures.

Application of Composite Materials to Space Structures

1988 ◽  
Vol 12 (2) ◽  
pp. 49-56
Author(s):  
D.G. Zimcik
Keyword(s):  
Composite Materials ◽  
Environmental Effects ◽  
High Performance ◽  
Polymer Matrix Composites ◽  
Space Environment ◽  
Space Structures ◽  
Matrix Composites ◽  
Performance Space ◽  
Performance Requirements ◽  
Advanced Composite Materials

Advanced composite materials are playing an increasingly important role in the design and fabrication of high performance space structures. Composite materials may be tailored for a particular application to establish a unique combination of high specific stiffness and strength, dimensional stability and specific damping which makes these materials ideal candidates for many applications in the hostile space environment. Demonstrative examples of typical applications to primary structures and payloads, each with a different set of performance requirements, are presented in this paper. Unfortunately, the use of polymer matrix composites for very long exposure to space has not been without problems due to various environmental effects which are discussed. The use of metal matrix composites is proposed as a possible solution to the problem. However, an understanding of the fundamental properties of composites and their response to space environmental effects is essential before the full benefit of these materials can be realized.

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