Modeling The Microwave Frequency Dielectric Properties of Thermoplastic Composite Materials

1992 ◽  
Vol 269 ◽  
Author(s):  
Mitchell L. Jackson ◽  
Curtis H. Stern
Keyword(s):  
Composite Materials ◽  
Dielectric Properties ◽  
Volume Fraction ◽  
Perturbation Technique ◽  
Resonant Cavity ◽  
Microwave Frequency ◽  
Thermoplastic Composite ◽  
Fiber Volume ◽  
Thermoplastic Matrix ◽  
Rotation Procedure

ABSTRACTMixture models were studied in an effort to predict the microwave frequency permittivities of unidirectional-fiber-reinforced thermoplastic-matrix composite materials as a function of fiber volume fraction, fiber orientation relative to the electric field, and temperature. The permittivities of the constituent fiber and plastic materials were measured using a resonant cavity perturbation technique at 9.4 GHz and at 2.45 GHz. The permittivities of the composite specimens were measured using a reflection cavity technique at 9.4 GHz and at 2.45 GHz. Simple “rule-of-mixtures” models that use the fiber and plastic permittivities have been found to approximate the complex dielectric properties of the composite for varied fiber volume fractions. The permittivities of oriented composites were modeled using a tensor rotation procedure. Composite permittivities were modeled with temperature up to the glass transition temperature of the thermoplastic matrix.

Mechanics of Natural Composites

1990 ◽  
Vol 218 ◽  
Author(s):  
Joseph E. Saliba ◽  
Rebecca C. Schiavone ◽  
Stephen L. Gunderson ◽  
Denise G. Taylor
Keyword(s):  
Composite Materials ◽  
Modulus Of Elasticity ◽  
Fiber Volume Fraction ◽  
Volume Fraction ◽  
Structural Response ◽  
Sensitivity Study ◽  
Fiber Volume ◽  
Fiber Size ◽  
Natural Composites ◽  
As Stress

AbstractThis study was initiated to investigate the structural response of the bessbeetle to determine potential advantageous ramifications and effects on the optimization of synthetic composite materials. The result of the micromechanics sensitivity study of various parameters are presented. Variables such as fiber size and shape, fiber volume fraction, ratio of modulus of elasticity of fiber over matrix, are changed one variable at a time, and the response quantities such as stress and tranverse modulus are presented.

MANUFACTURING TECHNOLOGIES OF POLYMER COMPOSITE MATERIALS ON THERMOPLASTICS (review)

2021 ◽  
pp. 78-86
Author(s):  
A.E. Sorokin ◽  
◽  
V.A. Sagomonova ◽  
A.P. Petrova ◽  
L.V. Solovyanchik ◽  
...  
Keyword(s):  
Composite Materials ◽  
Residual Stresses ◽  
Polymer Composite ◽  
Technological Process ◽  
Thermoplastic Composite ◽  
Strength Characteristics ◽  
Polymer Composite Materials ◽  
Complex Products ◽  
Thermoplastic Matrix ◽  
Manufacturing Technologies

Various technologies for the production of prepregs based on a thermoplastic matrix and composite materials based on them are considered. Their advantages over the technologies of manufacturing polymer composite materials based on a thermosetting matrix are presented. It is shown that the use of melt technology allows the production of fiberglass with the highest level of strength characteristics. An algorithm for estimating residual stresses in a thermoplastic composite to optimize the technological process of producing complex products is described.

Fatigue damage analysis of fiber-reinforced polymer composites—A review

2018 ◽  
Vol 37 (9) ◽  
pp. 636-654 ◽  
Author(s):  
Md. Touhid Alam Ansari ◽  
Kalyan Kumar Singh ◽  
Mohammad Sikandar Azam
Keyword(s):  
Composite Materials ◽  
Polymer Composites ◽  
Fatigue Damage ◽  
Fiber Volume Fraction ◽  
Volume Fraction ◽  
Fiber Reinforced Polymer ◽  
Fiber Reinforced ◽  
Fiber Volume ◽  
Reinforced Polymer ◽  
Fiber Reinforced Polymer Composites

Fiber-reinforced polymer composites are becoming suitable and substantial materials in the repair and replacement of conventional metallic materials because of their high strength and stiffness. These composites undergo various types of static and fatigue loads during service. One of the major tests that conventional and composite materials have to experience is fatigue test. It refers to the testing for the cyclic behavior of materials. Composite materials are different from metals, as they indicate a distinct behavior under fatigue loading. The fatigue damage and failure mechanisms are more intricate in composite materials than in metals in which a crack initiates and propagates up to fracture. In composite materials, several micro-cracks initiate at the primary stage of the fatigue growth, resulting in the initiation of various types of fatigue damage. Fiber volume fraction is an important parameter to describe a composite laminate. The fatigue strength increases with the increase of the fiber volume fraction to a certain level and then decreases because of the lack of enough resin to grip the fibers. The fatigue behavior of fiber-reinforced polymer composites depends on various factors, e.g., constituent materials, manufacturing process, hysteresis heating, fiber orientation, type of loading, interface properties, frequency, mean stress, environment. This review paper explores the effects of various parameters like fiber type, fiber orientation, fiber volume fraction, etc. on the fatigue behavior of fiber-reinforced polymer composites.

Molding of PBO fabric reinforced thermoplastic composite to achieve high fiber volume fraction

2013 ◽  
Vol 34 (6) ◽  
pp. 953-958 ◽  
Author(s):  
Anchang Xu ◽  
Limin Bao ◽  
Mitsuo Nishida ◽  
Atsuhiko Yamanaka
Keyword(s):  
Fiber Volume Fraction ◽  
Volume Fraction ◽  
Thermoplastic Composite ◽  
Fiber Volume ◽  
High Fiber

Bending Properties of Four-Layer Biaxial Weft Knitted Fabric Reinforced Composite Materials

2012 ◽  
Vol 182-183 ◽  
pp. 89-92
Author(s):  
Liang Sen Liu ◽  
Ye Xiong Qi ◽  
Jia Lu Li
Keyword(s):  
Composite Materials ◽  
Composite Laminates ◽  
Fiber Volume Fraction ◽  
Bending Strength ◽  
Volume Fraction ◽  
Bending Properties ◽  
Fiber Volume ◽  
Reinforced Composite ◽  
Weft Knitted Fabric ◽  
Bending Load

In this paper, a kind of composite laminates whose reinforcement is four-layer biaxial weft knitted (FBWK)fabric made of carbon fiber as inserted yarns has been made. The composite laminates have been impregnated with epoxy resin via resin transfer molding (RTM) technique. The samples of the experiments have been made from the composite laminates. The bending properties of the FBWK fabric reinforced composite materials with different fiber volume fraction have been investigated. The results show that the bending strength of this kind of composites increases with the fiber volume fraction increasing. The bending strength of FBWK reinforced composites with fiber volume fraction of 52% can reach 695.86 MPa. And the relationship between bending load and deflection is obviously linear.

Dielectric Studies of Admicelled Natural Rubber with Poly(3-Trimethoxysilylpropyl Methacrylate)

2013 ◽  
Vol 844 ◽  
pp. 373-376
Author(s):  
Suparat Nooma ◽  
Rathanawan Magaraphan
Keyword(s):  
Dielectric Constant ◽  
Composite Materials ◽  
Dielectric Properties ◽  
Chemical Modification ◽  
Natural Rubber ◽  
Microwave Frequency ◽  
Dielectric Studies ◽  
Frequency Range ◽  
Admicellar Polymerization ◽  
Methoxy Groups

In this work, 3-trimethoxysilylpropyl methacrylate (MPS) was used as a substrate for coating on natural rubber (NR) particles by admicellar polymerization. The incorporation of MPS monomer, consisting of silicon element and 3 reactive methoxy groups (R-Si(OCH3)), is expected to increase dielectric properties of NR. Under the admicellar polymerization, the R-Si(OCH3) groups can be hydrolyzed and condensed into polysiloxane existed on NR particles. This method aims to prepare composite materials from NR and MPS with various amounts of MPS. The effects of microwave frequency and chemical modification by admicellar polymerization were studied. The dielectric properties of admicelled natural rubber (adNR) with PMPS were investigated at 20 °C in a frequency range extended from MHz to GHz. The results showed that the dielectric constant of adNR increased with PMPS contents. To study the effect of crosslinking on the dielectric properties of adNR, the dielectric spectroscopy measurements were performed on prevulcanized and non-prevulcanized adNR. The investigation showed that the dielectric constant of non-prevulcanized adNR was less than prevulcanized adNR.

Investigating the Void Content, Fiber Content, and Fiber Orientation of 3D Printed Recycled Carbon Fiber

2019 ◽  
Vol 801 ◽  
pp. 276-281
Author(s):  
Peng Hao Wang ◽  
Ronald Sterkenburg ◽  
Garam Kim ◽  
Yu Wei He
Keyword(s):  
Composite Materials ◽  
Carbon Fiber ◽  
Fiber Orientation ◽  
Fiber Volume Fraction ◽  
Volume Fraction ◽  
Aerospace Industry ◽  
Void Content ◽  
Fiber Volume ◽  
3D Printed ◽  
Recycling Techniques

Composite materials continue to grow in popularity within the aerospace industry as the preferred material for manufacturing large airframe structures. However, the popularity of composite materials has also led to the increase in composite waste. As the popularity of composite materials continues to grow, the proper management and recycling of these composite waste materials becomes increasingly crucial to the sustainability of the environment. In order to investigate potential recycling techniques for composite waste, a team of Purdue University School of Aviation and Transportation Technology (SATT) faculty and students teamed up to investigate the characteristics of 3D printed recycled carbon fiber. A prototype 3D printed recycled carbon fiber part was used for the study. Through the use of microscopy and ImageJ image analyzing software, the researchers were able to determine the void content, fiber volume fraction, and fiber orientation of the prototype 3D printed recycled carbon fiber part and identified potential improvements to the 3D printing process in order to improve the 3D printed part’s characteristics.

Effect of the Carbon Nanotube Distribution on the Thermal Conductivity of Composite Materials

2015 ◽  
Vol 137 (3) ◽  
Author(s):  
Iman Eslami Afrooz ◽  
Andreas Öchsner
Keyword(s):  
Thermal Conductivity ◽  
Carbon Nanotubes ◽  
Finite Element Analysis ◽  
Composite Materials ◽  
Fiber Volume Fraction ◽  
Volume Fraction ◽  
Fiber Volume ◽  
Element Analysis ◽  
The Matrix ◽  
Good Agreement

Finite element analysis has been employed to investigate the effect of carbon nanotubes (CNTs) distribution on the thermal conductivity of composite materials. Several kinds of representative volume elements (RVEs) employed in this study are made by assuming that unidirectional CNTs are randomly distributed in a polymer matrix. It is also assumed that each set of RVEs contains a constant fiber volume fraction and aspect ratio. Results show that randomness—the way in which fibers are distributed inside the matrix—has a significant effect on the thermal conductivity of CNT composites. Results of this study were compared using the analytical Xue and Nan model and good agreement was observed.

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