Honeycomb Composite Materials Research Articles

Identification of Defects in Products Made from Honeycomb Composite Materials Using Infrared Scanning Thermography

Identification of Defects in Products Made from Honeycomb Composite Materials Using Infrared Scanning Thermography

Preliminary Hybrid Joint Analysis for Aircraft Structures

Metal-composite joints, or hybrid joints are prevalent in aerospace structures due to their high strength and low weight. Such structures are usually found in areas where because of the load configuration, the use of composite materials is possible. Thereby, the analysis of such areas needs to consider both components, the metallic and the composite part. In this paper a hybrid joint is analyzed, consisting of a metallic stiffener, a multilayered honeycomb composite material, and joining fasteners, which constitute the joint between the isotropic and orthotropic materials. The present article has two main purposes: the first is to illustrate a pre-design procedure aimed to evaluate the load-carrying capability of a hybrid joint structure, thereby giving an estimate if the structure can withstand the given loading conditions; the second purpose is to present two types of finite element modeling techniques, one that captures the real geometric structure of the composite material and another which uses a simplified equivalent model, based on the desired level of evaluation of the composite material part. A comparison between the two models is made, highlighting the advantages and disadvantages of the two forms of evaluations. For the metallic parts - stiffener and fasteners, both static and fatigue analyses were performed, as fatigue failure represents the common service failure mode for this type of structural components.

Research and development of honeycomb door of full-side open boxcar and its simulation and vibration test

PurposeThis study aims to reduce the weight of the door, improve the operating efficiency and ensure the safety of vehicle operation.Design/methodology/approachBased on traditional aluminium alloy doors, a new type of honeycomb composite material was developed. Tests were conducted to determine the honeycomb compression resistance, honeycomb and skin shear performance, plate bending, thermal conductivity and environmental protection. Eight doors were developed based on the full-side open structure, and static strength and stiffness analyses were performed simultaneously. To solve door vibration problems, modal analysis and test were carried out.FindingsThe test results showed that the weight of the door was reduced by more than 40% whilst ensuring the strength and stiffness of the vehicle. The first–sixth-order test mode of the door was increased by more than 14% compared with existing aluminium alloy doors.Originality/valueA new type of honeycomb composite material was used in this study. The test results showed that the weight of the door was reduced by more than 40% whilst ensuring the strength and stiffness of the vehicle. The 1st-to-6th order test mode of the door was increased by more than 14% compared with the existing aluminium alloy door.

Research on Acoustic Absorption Properties of Aramid Honeycomb Composite Material Reinforced by Polyimide Foam

To endue sound absorption behavior for aramid honeycomb core (ARHC), isocyanate‐based polyimide foam (IBPIF) with excellent thermal insulation and acoustic properties produced by a new formulation of foaming slurry is filled into ARHC by the free foaming route. As a core factor to adjust the cellular structure of IBPIF, the effect of water dosage on the acoustic behavior of IBPIF and IBPIF filled ARHC (IBPIF/ARHC) is studied, and the optimal formula to produce IBPIF/ARHC is filtered out. Results suggest that water dosage effectively regulates the cellular structure of IBPIF. When water dosage is 7.2 g, IBPIF has a large windows opening rate, which plays a positive role in sound absorption performance. IBPIF/ARHC‐3 has the best sound absorption property, which possesses a maximum sound absorption coefficient (α) of 0.9 at 1500 Hz. Its average α increases to 0.78 and shows an increase of 680% compared to ARHC. Meanwhile, the density of IBPIF/ARHC is only about 59 kg m−3. In 300–600 Hz range, IBPIF‐3 and ARHC show obvious synergy effects in sound absorption behavior. The average α of IBPIF‐3 and ARHC is only 0.3 and 0.06, respectively, and that of IBPIF/ARHC‐3 reaches up to 0.42. The thermal insulation performance of ARHC is also improved, and thermal conductivity decreases from 0.067 to 0.047–0.049 W (m K)−1.

An Efficient Method to Compute EM Scattering From Target Covered With Honeycomb Composite Material

A new electromagnetic scattering model of target with honeycomb composite material is proposed in this letter by combining equivalent reflection coefficient model with high frequency method. First, the honeycomb composite is regarded as a uniaxial media based on strong interference theory. Then, the reflection coefficient of honeycomb composite with perfect electric conductor is derived with generalized propagation matrix method. Finally, the derived reflection coefficients are introduced in shooting and bouncing rays and physical optics (SBR-PO) method to obtain the scattering characteristic of complex target covered with honeycomb material. Moreover, the SBR-PO method is accelerated by the Compute Unified Device Architecture and OptiX from Nvidia. The accuracy of our method was demonstrated by comparing with full-wave method and measured data, respectively. The scattering of target covered with honeycomb material are simulated and discussed in this letter.

Advantage analysis of aluminum honeycomb composite used in motorhomes

In the light weight, high weather resistance and environmental protection requirements of the panel used for the motorhome, aluminum honeycomb composite, new material with mature the quality improvement and material upgrading of the panel used for the motorhome. In this paper, the existing problems of the panel used for the motorhome and the properties of aluminum honeycomb composite are discussed, the advantages of applying aluminum honeycomb composite to the board of the motorhome are analyzed. The application of aluminum honeycomb composite materials to motorhomes will meet the requirements for improving the quality of panels, such as reduced in weight, environmentally friendly, non-combustible, recyclable, improved weather resistance and increased service life.

Multi-praseodymium-and-tungsten bridging octameric tellurotungstate and its 2D honeycomb composite film for detecting estrogen.

Under coordination driving force of tungsten and rare-earth (RE) bridges, we synthesized a novel giant multi-tungsten-and-RE-bridging octameric tellurotungstate (TT) [H2N(CH3)2]16K8Na6H10[Pr8(H2O)20W16O48][B-α-TeW9O33]8·70H2O (1) in CH3CN-H2O mixed solvent. The cluster anion {[Pr8(H2O)20W16O48][B-α-TeW9O33]8}40- features sixteen WVI bridges, eight PrIII bridges and eight trivacant Keggin [B-α-TeW9O33]8- fragments, which the square {W4O12} cluster can be imagined as a seed to induce the aggregation of eight [B-α-TeW9O33]8- fragments by coordination driving force of additional twelve WVI bridges and eight PrIII ions. Furthermore, the 2D 1@DODA (dimethyldioctadecyl ammonium bromide = DODA·Br) honeycomb composite material was prepared. The honeycomb morphology of the 1@DODA composite material provides rich binding sites for electrodepositing Au nanoparticles to make Au/1@DODA electrodes. The aptamer of 17β-estradiol (E2) hormone can be grafted to the Au/1@DODA electrodes via Au-S bonding interaction to construct the Au/1@DODA aptamer biosensors. By virtue of the specific recognition interaction of aptamer and the electrochemical signal amplification function of methylene blue and cDNA, the Au/1@DODA aptamer biosensors can realize the electrochemical detection of E2. This finding not only offers an electrochemical biosensing platform for detecting E2, but also expands POM-based composite materials in the applications of clinical detection and biological analysis.

Experimental study of the honeycomb composite material under high velocity impact

This study deals with the effect of complex material made from (Kevlar29, Honeycomb Aluminium and Carbon fibers) under high velocity is measured, also this material tested to specify the mechanical properties, then the high-impact loading utilizing the energy absorption tests were performed experimentally by using a gas gun device with shape of impactors flat cylindrical bullets. The discussion of the results of this work was termed under the failure of the coupling mode of the projectiles. The velocity level and defamatory affect the kinetic energy of the projectile. The thickness of the target has an impact on the projectile speed. The findings are discussed in terms of the work done to link the failure modes with the kinetic energy fall of the projectile and its effect on ballistic maximum velocity. The effect on the rate of the target thickness was then addressed. The vitality assimilation was anticipated by expecting that all out work done in the disfigurement of the plates is comparable to the total loss of the motor vitality of the shot. The connection between possible speed and the thickness of composite material was perceived. The hypothetical outcomes demonstrated great understanding contrasted and the test work.

Experimental study of the honeycomb composite material under high velocity impact

This study deals with the effect of complex material made from (Kevlar29, Honeycomb Aluminium and Carbon fibers) under high velocity is measured, also this material tested to specify the mechanical properties, then the high-impact loading utilizing the energy absorption tests were performed experimentally by using a gas gun device with shape of impactors flat cylindrical bullets. The discussion of the results of this work was termed under the failure of the coupling mode of the projectiles. The velocity level and defamatory affect the kinetic energy of the projectile. The thickness of the target has an impact on the projectile speed. The findings are discussed in terms of the work done to link the failure modes with the kinetic energy fall of the projectile and its effect on ballistic maximum velocity. The effect on the rate of the target thickness was then addressed. The vitality assimilation was anticipated by expecting that all out work done in the disfigurement of the plates is comparable to the total loss of the motor vitality of the shot. The connection between possible speed and the thickness of composite material was perceived. The hypothetical outcomes demonstrated great understanding contrasted and the test work.

FINITE ELEMENT MODELING OF LAPAN-A5/CHIBASAT DEPLOYABLE SOLAR PANEL COMPOSITE PLATE

LAPAN-A5/ChibaSat, that will carry synthetic aperture radar payload, requires a lot more power generation capacity, compared to its predecessor. Therefore, its solar panel will be deployed in orbit to ensure maximum sun exposure. Since the deployable system requires solar panel plate that lightweight and strong, honeycomb composite material is selected. The selection of such material requires special treatment in the satellite structural stiffness calculation. The objective of the research is to find simple stiffness model of the plate, so that later it can be integrated with the total satellite structural model and used by launch authority in its total vehicle modal analysis. The modeling used finite element software, and the simplified honeycomb model is validated using standar plate stiffnes problem. After model validation, the boundary condition as in the LAPAN-A5/ChibaSat deployable system is imposed. The result shows that the stiffness of the deployable solar panel plate has met the launch requirement of PSLV’s auxiliary payload. Therefore, the design mode can be used in the development of LAPAN-A5/ChibaSat.

Numerical evaluation of the performances of a multilayered

The improvements made in the field of the research of composite materials led to the wide usage of composite materials, which, nowadays, tend to replace traditional metallic materials in engineering applications. In this paper, the performances of a landing gear, subjected to dynamic loadings and made of a multilayered honeycomb composite material are evaluated in comparison with traditional metallic materials using numerical simulation. The obtained values of mechanical stress for the hybrid landing gear design are lower compared to those for a landing gear made entirely of aluminium. The use of the multilayered honeycomb composite material decreases the values of the stresses, for the given load case. Also, reduction of the mass of the landing gear improves flight dinamics and increases manoeuvrability.

Finite Element Analysis of the Multilayered Honeycomb Composite Material Subjected to Impact Loading

The main purpose of this paper is the study the behavior of four multilayered composite material configurations subjected to different levels of low velocity impacts, in the linear elastc domain of the materials, using experimental testing and finite element simulation. The experimental results obtained after testing, are used to validate the finite element models of the four composite multilayered honeycomb structures, which makes possible the study, using only the finite element method, of these composite materials for a give application.

Electromagnetic Characterization of Aircraft Composite Materials and its Effects on the Antenna Performance

This paper presents an electromagnetic characterization of aircraft composite materials, as well as numerical and experimental analyses of its effects on the antenna performance. Two uncalibrated S-parameters characterization methods have been applied for retrieving the complex electrical permittivity in the L- and C-band, namely: Air-region method and Sample-shifted method. Dielectric constants of 4.6 and 1.84 and loss tangent of 2.0x10 -2 and 6.1x10 -2 have been obtained for fiberglass and honeycomb composite materials, respectively. A 3.0-meters prototype of an Embraer light jet aircraft dorsal fin was fabricated and used in the experiments in a semi-anechoic chamber in order to evaluate the impact of installing aeronautical VHF and L-band antennas on a fuselage made of composite materials.

Studies on the effect of shape-stabilized PCM filled aluminum honeycomb composite material on thermal control

A new kind of composite material combined the shape-stabilized phase change material with aluminum honeycomb used in thermal control was prepared and investigated both theoretically and experimentally. The shape-stabilized PCM prepared in this paper was experimentally validated to have stable phase change temperature, latent heat and thermal conductivity after several cycles of melting and solidification. The metal honeycomb structure could enhance the thermal conductivity and structural strength of organic PCM effectively with adding little weight to the system. The stress tolerance limit (STL) of the composite material was measured and compared with that of the shape-stabilized PCM. The results showed that the STL was promoted by 25.2%. A performance test experiment of the PCM thermal control unit was accomplished and a numerical model was established for further study. The temperature variations of the numerical model were in good agreement with the experimental data. Results showed that the addition of aluminum honeycomb structure could make the temperature variation of the heating source in a much smaller range, compared with the result that without aluminum honeycomb. The shape-stabilized PCM/aluminum honeycomb composite material showed the best combination properties of heat transfer and mechanical behavior.

Numerical research of the static stability of honeycomb composite materials

The article presents a numerical research of static stability of honeycomb-filled sandwich panels used injet engine casing. The application of honeycomb-filled panels in aircraft manufacture has a number of advantagesover one-piece constructions. For the assessment of the stability of the whole structure the static-stateanalysis of a full-scale model was performed at the initial stage of the research and the radial and axial displacementsas well as tensile and compressive stresses were evaluated. A model of the periodic cell of a honeycombsandwich panel was developed at the next stage. The use of such a model in the stability analysis is justified bythe absence of boundary effects. To account for the initial shape deformation and the plastic material behavior anon-linear boundary-value problem was incorporated in the analysis. The influence of the honeycomb material(aluminum alloy and fiberglass), the time step, and the finite element size on the stability parameter was evaluated.The analysis of the results obtained was carried out, graphs were constructed. Further research of the honeycombsandwich panel behavior demands more in-depth analysis of structurally similar elements and full-scalestructures.

Simultaneous Estimation of Principal Thermal Conductivities of an Anisotropic Composite Medium: An Inverse Analysis

This paper reports the results of an experimental study to determine the principal thermal conductivities (kx,ky, and kz) of an anisotropic composite medium using an inverse heat transfer analysis. The direct problem consists of solving the three dimensional heat conduction equation in an orthotropic composite medium with the finite difference method to generate the required temperature distribution for known thermal conductivities. The measurement technique involves dissipating a known heat flux at the central region of a square sample and allowing it to conductively transfer the heat to an aluminium cold plate sink via a square copper ring. At steady state, temperatures at 28 (19 are used for retrievals due to symmetry) discrete locations are logged and used for parameter estimation. The entire measurement process is conducted in a vacuum environment. The inverse heat conduction problem (IHCP) for retrieving the orthotropic thermal conductivity tensor(parameter estimation) is then solved using a two layer feed forward back propagation artificial neural network (ANN) trained using the Levenberg–Marquardt algorithm (LMA), with temperatures as input and thermal conductivity values kx,ky, and kz as the output. The method is first validated against a stainless steel(SS-304) sample of known thermal properties followed by the determination of the orthotropic conductivities of the honeycomb composite material.

Determination of Load Distributions on Main Helicopter Rotor Blades and Strength Analysis of Its Structural Components

To define load spectra of main rotor blades in this study computational fluid dynamics (CFD) software is used. The aim of the present investigation is the development of a CFD computation procedure capable of accurately simulating the flow around a full helicopter especially around main rotor blades. For this purpose the complete helicopter configuration including fuselage, main rotor and tail rotor computer-aided design (CAD) models are used in CFD modeling and determination of loads. Primary attention in this investigation is focused on defining loads of main rotor blades because metal trailing edge segments of these blades were replaced with a new segments made from honeycomb composite materials. As critical structural parts with respects to strength here are glued joints between metal and composite segments of trailing edge are considered. For precise stress analysis of these segments, including glued joints, the finite element method is used.

Research on Curved Surface Forming of Nomex Honeycomb Material Based on Ultrasonic NC Cutting

This article introduced the Nomex honeycomb composite material, analyzed the insufficient of the traditional milling process in Nomex honeycomb composite processing, and proposed using the characteristics of ultrasonic cutting combined with NC technology to process the honeycomb composites. It analyzed the forming principle of the corresponding curved surface according to the special ultrasonic cutting tool and cutting method, and established a corresponding error.

A Thermal Analysis Approach for the Detection of Damage in Carbon—Carbon Type Composite

This research work focuses on the viability of applying a thermal method for detecting damage in carbon fiber and sandwich composites. The fundamental of the technique analyzed herein is based on changes in the temperature profiles as a heat flux travels through the material. A 3-D finite element simulation provides good qualitative results and an inexpensive tool for detecting the presence of damage and its exact location. The influence of parameters, such as damage depth, diameter, and limiting detection time is also studied. This thermal technique is also implemented experimentally in an attempt to detect damage. Experimental results are compared to the numerical simulations in terms of damage locations and temperature trends. Damage is detected experimentally for metal surfaces and carbon fiber composite materials with simple structural arrays. However, for honeycomb composite materials, the detection of damage from the thermal standpoint was somewhat difficult due to the complex temperature profile generated within the material, due to its complex array of materials.