Filament Winding Method Research Articles

SiCf/SiC 복합체 튜브의 표면조도 및 섬유 부피 분율에 미치는 필라멘트 와인딩 방법의 영향

Silicon carbide and its composites are being considered as a nuclear fuel cladding material for LWR nuclear reactors because they have a low neutron absorption cross section, low hydrogen production under accident conditions, and high strength at high temperatures. The SiC composite cladding tube considered in this study consists of three layers, monolith CVD SiC - SiC f /SiC composite .monolith CVD SiC. The volume fraction of SiC fiber and surface roughness of the composite layer affect mechanical and corrosion properties of the cladding tube. In this study, various types of SiC fiber preforms with tubular shapes were fabricated by a filament winding method using two types of Tyranno SA3 grade SiC fibers with 800 filaments/yarn and 1600 filaments/yarn. After chemical vapor infiltration of the SiC matrix, the surface roughness and fiber volume fraction were measured. As filament counts were changed from 800 to 1600, the surface roughness increased but the fiber volume fraction decreased. The SiC f /SiC composite with a bamboo-like winding pattern has a smaller surface roughness and a higher fiber volume fraction than that with a zigzag winding pattern.

Residual torsional properties of composite shafts subjected to impact loadings

This paper presents an experimental and numerical study to investigate residual torsional properties of composite shafts subjected to impact loadings. E-glass/epoxy, carbon/epoxy and E-glass–carbon/epoxy hybrid composite shafts were manufactured by filament winding method. Composite shafts were impacted at 5, 10, 20 and 40J energy levels. Force–time and energy–time histories of impact tests were recorded. One composite shaft with no impact, and four composite shafts with impact damage, five in total, were tested under torsion. Torque-twisting angle relations for each test were obtained. Reduction at maximum torque and maximum twisting angle induced by impact loadings were calculated. While 5J impact did not cause significant reduction at maximum torque and maximum twisting angle, remaining impact loadings caused 34–67% reduction at maximum torque, and 30–61% reduction at maximum twisting angle. Reductions increased with increasing energy levels and varied depending on the material of composite shafts. The 3-D finite element (FE) software, Abaqus, incorporated with an elastic orthotropic model, was then used to simulate the torsion tests. Good agreement between experimental and numerical results was achieved.

Properties and Performance Analysis of Woven Roving Composite Laminates for Automotive Panel Board Applications

Now-a-days natural Fibers are employed in various engineering applications because of their high tensile strength, low thermal expansion, high strength to weight ratio and good corrosion resistance. In this paper, woven roving composite laminates are prepared to produce automotive panel boards. Even though, various methods are available for preparing composites like Pultrusion method, filament winding method and hand layup method, hand lay method is used in this paper. The bundles of woven roving are alkalized at concentration between 1.2 and 6% of NaoH. Then, the treated fibres with increased strength are used as reinforcement with Epoxy LY556 resin with HY951 hardener under room temperature. The tensile analysis is conducted for the specimens like plain specimen, specimen with circular central hole and specimen with rectangular central hole. The results show that plain specimen is having more strength followed by circular hole and then rectangular hole specimens. It suggested that the case industry can make near optimal circular hole for its components by replacing rectangular hole.

Buckling Analysis of Composite Lattice Cylindrical Shells with Ribs Defects

In this paper, the buckling behavior of a composite lattice cylindrical shell is studied and effects of rib defects on the distribution of stress field and buckling response of the shell is investigated. A three dimensional finite element buckling analysis of the lattice shell is carried out using ANSYS suit of program. Geometrical data and material properties of the shell are obtained from the specimens made by filament winding method. Effects of various parameters including the geometrical ratios, defects of ribs on buckling response of the shell are studied. Buckling loads of composite lattice cylindrical shells under axial and shear forces have been obtained experimentally and results are compared with finite element results.

Improvement of Impact Damage Resistance of Epoxy-Matrix Composites Using Ductile Hollow Fibers

Fiber reinforced polymer structures typically respond very poorly to transverse impact events. In this study, some experimental investigations are performed on the low velocity impact behavior of unidirectional hollow, solid and hybrid (hollow/solid) polyester fiber composites. The materials are fabricated in a curved shape using filament winding method. The impact tests are applied on the simply supported specimens by a drop weight impact test apparatus at five levels of energy. To present a proper comparison on the results, the various densities of the materials are considered as normalizing coefficients. It is observed that in the hollow fiber composites cracks appear at an appreciably higher amount (93%) of impact energy than the solid ones.

110 改良型同時多層巻回法によるCFRP円筒材のねじり強度に及ぼす積層構成の影響

Application of CFRP tubes for torque transmission shafts is expected to improve driving performance and natural frequency as well as fuel efficiency. CFRP tubes manufactured by modified simultaneous multi ply winding method have less voids and fiber waviness compared with conventional CFRP tubes manufactured by filament winding method, and the modified CFRP tubes showed 20% improvement of the static torsional strength. We investigated the fracture mechanisms of CFRP tubes by modified simultaneous multi ply winding method. As a result, a delamination from the prepreg end occurred at the innermost layer and it progressed through ±45° interlayer just before the failure of the specimen. In order to apply CFRP tubes to torque transmission shafts, it is expected to design the stacking sequence appropriately for preventing the delamination from the prepreg end in terms of long-time reliability. Thus in this study, we investigated an influence of the stacking sequence of CFRP tubes on their torsional strength. According to static torsional tests, it was revealed that the specimen with less lamination angle differences caused less delamination due to relaxation of interlaminar shear stress. Moreover, torsional strength was improved moderately mainly because the small lamination angle differences delayed the initiation of the delamination.

Filament Winding Moulding of Biodegradable Composites Using Ramie Yarns

An experimental investigation of fabricating biodegradable composite pipes by filament winding (FW) method using ramie yarn as continuous fibre reinforcements is conducted. Though ramie fibres are discontinuous fibres in origin, ramie yarns can be handled as continuous fibre due to high aspect ratio of the fibre. Influence of use of the yarn on mechanical properties of the FW pipes is also evaluated. Axial and circumferential tensile tests are conducted for the FW pipes fabricated with various winding tensions. Results demonstrate that the winding tension affects not fracture load but only fibre volume fraction of the composites. Furthermore, properties of ramie yarn in FW pipes have been focused on. It has been shown that the elastic modulus of FW pipes using ramie yarns is lower than that of angle-plied laminates while mechanical properties of FW pipes and angle-plied laminates using glass or carbon fibre are comparable. From experimental evidences, it has been found that waviness of the ramie yarns caused by their own large diameter strongly affects the mechanical properties of the FW pipes, and that the ramie yarns do not exert their properties adequately in the FW pipes.

Seawater effect on impact behavior of glass–epoxy composite pipes

The effect of seawater immersion on impact behavior of glass–epoxy composite pipes is experimentally investigated. Glass–epoxy pipes with [±55°]3 orientation were fabricated using filament winding method. Composite pipes were selected for four different diameters as 50mm, 75mm, 100mm, and 150mm. The pipes were immersed in artificial seawater having a salinity of about 3.5% for 3, 6, 9, and 12months in laboratory conditions. At the end of the conditioning period, the specimens were impacted at three distinct energy levels as 15J, 20J, and 25J at ambient temperature of 20°C. The comparisons between the dry and immersed cases were carried out by using contact force, deflection and absorbed energy data of the impact tests. Results show that moisture absorption, salt in seawater, diameter of specimen and residual stresses produced by manufacturing process of the composite pipe have significant effect on maximum contact force, maximum deflection, absorbed energy and failure of composite pipes according to exposure time to seawater.

Compressive damage in filament‐wound carbon/carbon composites

AbstractThe processing characteristics and the induced compressive damage in filament‐wound carbon/carbon composites were examined. Tubular carbon/phenolic composites were made by the filament winding method. The inside diameter was 25.4 mm and the nominal thickness was 2.5 mm. The cured composites were then carbonized. Three more cycles of matrix densification were repeated. After densification, the composites were graphitized at 2600°C. Compressive tests were then carried out for the cured, carbonized, and graphitized composites. The load was applied directly on the end of the tube. The loading response and the induced damage were studied. Their microscopic fracture behaviors were examined by optical and scanning electron microscopes. With the heating temperature increased, the damage modes shifted from a ductile fracture in the cured composites to a more brittle fracture in the graphitized composites. The resulting strength and stiffness were also decreased significantly with the temperature. Kinking of fibers was the major mode in the cured specimens, while separation of bundles became more prominent in the graphitized specimens. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers

Application of low temperature co-fire ceramics on in-plane micro-generator

This study presents a new method of fabrication of in-plane rotary electromagnetic micro-generator. Low temperature co-fired ceramics (LTCC) technology is applied to fabricate micro-coil for the micro-generator. The process of the LTCC micro-coil provides more cost-effective and time-saving approaches than other process such as Lithographie Galvanoformung Abformung (LIGA), LIGA-like and filament-winding methods. This micro-generator consists of multilayer planar LTCC silver (Ag) micro-coil and multipolar hard magnets of Nd/Fe/B (neodymium, iron, and boron). This study focuses on the fabrication and test of the in-plane micro-generator to obtain a high power output. There are three different configurations of planar LTCC Ag micro-coils investigated in this study, which are sector-shaped, circle-shaped, and square-shaped micro-coils. Both the printing linewidth and spacing of these micro-coils are 100 μm. The multipolar hard magnet Nd/Fe/B with outer diameter of 9 mm and thickness of 700 μm is molded and sintered. The self-designed measurement facility of the power output is established, which consists of a drive mechanism and data acquisition units. A prototype of the micro-generator is as small as 9 mm × 9 mm × 1 mm in volume size. The experimental results show that the micro-generator with sector-shaped micro-coil has the highest power output of 1.89 mW, and the effective value of the induced voltage of 205.7 mV at 888.3 Hz (about 13,325 rpm) is achieved.

Enhancement of the crack growth resistance of a carbon/epoxy composite by adding multi-walled carbon nanotubes at a cryogenic temperature

Abstract The improvement of crack resistance is essential to the application of fiber reinforced composites for cryogenic use. In this study, the authors attempted to enhance the crack resistance of a carbon/epoxy composite by adding multi-walled carbon nanotubes (MWNTs) into the resin formulation. Prior to assessing the effect of MWNTs, the effect of a toughened epoxy resin on the mode I interlaminar fracture toughness was investigated at −150 °C using double cantilever beam (DCB) specimens. It was found that the degree of fracture toughness enhancement obtained from application of the toughened epoxy at cryogenic temperature was less than that at room temperature, due to embrittlement of the epoxy resin. MWNT-added carbon/epoxy unidirectional prepregs were fabricated via a filament winding method with different concentrations of MWNTs (0.0 wt% for baseline, 0.2 wt% and 0.7 wt%). Material systems blended with 0.2 wt% and 0.7 wt% of MWNTs showed enhanced fracture toughness and low crack density at the cryogenic temperature.

Improvement of the Crack Resistance of a Carbon/Epoxy Composite at Cryogenic Temperature

The improvement of crack resistance is essential to the application of composites for cryogenic use such as structures storing liquid oxygen or liquid hydrogen. In this study, an effort to improve the crack resistance of a carbon/epoxy composite was made by adding MWNTs (Multi-Walled Carbon Nanotubes) to the resin formulation. Ahead of the investigation of MWNT effect, an epoxy matrix system was developed by mixing two kinds of epoxy resins and adding additives for high toughness at cryogenic temperature. The MWNT-added carbon/epoxy unidirectional prepregs were fabricated by way of a filament winding method with different concentrations of MWNTs (0.2wt% and 0.7wt%). The mechanical tests were performed inside an environmental chamber at room temperature and -150°C. The developed material system has little influence on interlaminar shear strength but resulted in higher fracture toughness at -150°C than those of baseline material. Microcrack densities after thermo-mechanical cycles were measured through an optical microscope.

Development of a rotary electromagnetic microgenerator

This study presents the development of an in-plane rotary electromagnetic microgenerator, which consists mainly of a multilayer planar copper (Cu) microcoil and a multipolar hard magnet made of NdFeB, the whole volume of which is approximately 5 × 5 × 2 mm3. The study focuses on the design and manufacturing required to obtain a high power generation output, and an analytical model is developed to predict the power output for different designs of microgenerators. The geometric pattern design of the Cu planar microcoil is manufactured using the filament winding method. Both the linewidth and spacing of the microcoil are 30 µm. The multipolar hard NdFeB magnet is molded and sintered, and a specially designed piece of equipment (a yoke) is used to magnetize the NdFeB magnet to produce an external magnetic field. After magnetization, an anisotropic residual induction (Br) of 1.44 tesla is produced. The theoretical model of this power microgenerator is evaluated and compared with experimental results, and it is found that the analytical simulation shows a good agreement with the experimental results. The induced electromotive force (EMF) is 111.2 mV and a maximum power output of 0.412 mW at a frequency of 149.3 Hz is obtained.

On-board Strain Measurement of a Cryogenic Composite Tank Mounted on a Reusable Rocket using FBG Sensors

This article presents the real-time strain measurement of a composite liquid hydrogen (LH2) tank using fiber Bragg grating (FBG) sensors. The tank was composed of carbon fiber reinforced plastic (CFRP), and an aluminum liner was fabricated by the filament winding method and mounted on a reusable rocket. This rocket (vertical takeoff and landing) is called a reusable rocket vehicle test (RVT) and was developed by the Institute of Space and Astronautical Science of the Japan Aerospace Exploration Agency (ISAS/JAXA). Considering the high operational pressure and the iterative use of the tank, its structural integrity must be guaranteed. Thus, the authors have attempted a real-time strain measurement of the composite LH2 tank using FBG sensors during rocket operations. First, the adhesive properties of the FBG sensors were investigated at cryogenic temperatures. As a result, UV-coated FBG sensors and polyurethane adhesives were adopted. An onboard FBG demodulator was then developed to be mounted on the rocket and its performance was assessed. Finally, the strain measurement was attempted during the flight experiments of the RVT using the onboard FBG demodulator. FBG sensors were glued on the surface of the composite LH2 tank and connected to the onboard FBG demodulator. During these rocket operations, the output of the onboard FBG demodulator was continuously monitored via a telemetry system. The results obtained by the demodulator agreed well with those of the conventional foil strain gage.

Dependence on winding tensions for stability of a superconducting coil

The purpose of this study is to manufacture a high performance superconducting pulse coil by using high strength polyethylene fiber (DF; Dyneema ® fiber) reinforced plastic (DFRP) or Dyneema–glass hybrid composite fiber reinforced plastic (DGFRP) as material of a coil bobbin, which has negative thermal expansion, low frictional coefficient and high thermal conductivity. Description in this paper is as follows. First, thermal strains of several kinds of FRP pipes made by filament-winding (FW) method are measured, and the measured results well agreed with calculated ones by our proposed calculation method about thermal strains of a FW-pipe form. This shows that thermal expansion can be controlled by the proposed design technique of a DGFRP FW-pipe. Moreover, frictional coefficients of FRP plates using as coil structural material are measured and frictional heats are calculated for respective material when contact forces are changed. From these results, we find that the lower winding tension of a coil generates the smaller frictional heat when the frictional coefficient of the coil structural material is low. Furthermore, we systematically measure quench characteristics of many specimens of small superconducting coils using DFRP or DGFRP bobbins with different thermal expansions. From the results of quench tests, we find that the higher winding tension’s coils tend to decrease quench current when the coil’s bobbin expanded to a direction of circumference during the cooling down to cryogenic temperature, and suitable values of winding tension in a coil are located in region of 2–4 kg/mm 2. Finally, we design and manufacture 100 kJ class superconducting pulse coil by using a DGFRP bobbin, which wound in winding tension of 4 kg/mm 2. In addition, we prepare another 100 kJ class coil with the higher winding tensions of 8 kg/mm 2, and the quench characteristics of the coils are compared. The quench currents in the coils exceed the 95% rating on the load line for critical current value of a conductor, and a coil with winding tension of 4 kg/mm 2 is more stable.

Improvement in stability of superconducting coil by different mechanical properties of bobbins

The Dyneema ® fiber reinforced plastic (DFRP) expands to a direction of the Dyneema fibers during cooling process. Therefore, a winding angle in Dyneema fibers of the DFRP bobbin manufactured by the filament winding method makes possible to control thermal expansion/contraction properties to the circumferential direction on the bobbin. Moreover, DFRP’s frictional coefficients are considerably low. These properties are extremely different from those of GFRP which is generally used as the spacers and the bobbins of superconducting coils. In this paper, the coils fabricated with DFRP and GFRP bobbins are examined in DC and AC operating experiments. When the coil was operated under DC current, the low frictional properties of the coils having DFRP bobbins improved the instability due to the wire motion, on the other hand, in case of AC operating test, the thermal expansion properties of DFRP bobbin could reduce the mechanical losses between the wire and the bobbin.

Coil bobbin composed of high strength polyethylene fiber reinforced plastics for a stable high field superconducting magnet

High field superconducting solenoid magnets sometimes quench by wire motion induced by electro-magnetic force. High strength polyethylene fiber reinforced plastic (DFRP) has a negative thermal expansion coefficient and a low frictional coefficient. DFRP pipes made by filament winding method could be constructed so as to expand in the circumferential direction when cooled to low temperature with an appropriate selection of winding angle and shape of the pipes. In the case of a superconducting coil wound on a DFRP bobbin, it is expected that wire motions in high field are decreased by expansion of the coil bobbin. In this work, sample coils wound on DFRP bobbin and stainless steel (SUS) bobbin were prepared. The sample coil voltages were measured during increasing current in background external field. The coil using SUS bobbin showed many sharp peaks in tap voltage induced by quick wire motions. In contrast, those using DFRP bobbin showed no peaks. These results suggest that the quick wire motions were constrained by DFRP bobbin which had a negative thermal expansion coefficient and a low frictional coefficient.

Modal separation of work-of-fracture of carbon/carbon composites

Modal separation of work-of-fracture was carried out for unidirectional C/C composites in order to characterize their multi-modal fracture behavior. The C/C composites were prepared by filament winding method with a coal tar pitch as a matrix precursor, and followed by heat treatment at temperatures between 1000°C and 2800°C under argon flow. During single edge-notched beam tests, tensile fracture and interlaminar shear fracture were simultaneously observed in the specimens. In proportion to the fracture surface area, the total work done during fracture was divided into each fracture mode, and the modal work-of-fracture was obtained by dividing each modal dissipation energy by twice the corresponding modal fracture surface area. With increasing the heat treatment temperature, the modal work-of-fracture for the tensile mode gradually increased and reached a maximum of around 6 kJm−2 at a heat treatment temperature of 2000°C, whereas the modal work-of-fracture for the interlaminar shear mode remained constant around 20 Jm−2. Determination of these modal work-of-fracture values revealed quantitatively the contribution of each fracture mode to the total dissipation energy of the composites.

MODELING AND TENSION CONTROL OF FILAMENT WINDING PROCESS

Currently, a variety of fiber materials are extensively used in a number of fields. Carbon fiber (CF), carbon-fiber reinforced plastics (CFRP), and their products are especially popular because they have a higher tensile strength than metal materials. CFRP are generally formed by a filament-winding (FW) method. The winding pitch and tension controls of this process are key factors in making sound products. The purpose of the present research is to establish an advanced filament-winding system with real-time control of the winding tension. First, modeling of the Hoop-winding tension process(pattern) is studied in terms of a system identification technique. Secondly, two-degree-of-freedom (2-DOF) PID control is applied to the winding process, with the controller having been designed to use the Genetic Algorithm (GA). Based on the above, a tuning method of control gain using GA is proposed herein. Finally, the effectiveness of the proposed approach is demonstrated via control experiments. Futhermore, the controller designed for Hoop-winding process has been applied to the Helical-winding process in a more general case. Important suggestion to be developed is given from the frequency analisys, although control experimental results did not satisfied our control performance.

Compressive Strength of Composite/Concrete Cylinders after Low Energy Impact

This paper deals with the repair of the concrete cylinder by fiber reinforced composites fabricated through the filament winding method. Composites fabricated by the method can reinforce concrete cylinders efficiently because they provide comprehensive and multi-axial reinforcing effects. In this work, three winding angles were adopted to wind six layers of glass/epoxy composite jacket onto the concrete cylinder. These three winding angles combined with different lay-up sequence form seven types of composite/concrete cylinders. The compression after impact (CAI) test was conducted on the seven composite/concrete cylinders. These experiments were designed to investigate the influence of winding angles and lay-up sequence of the composite on the CAI strength. It is found that the highest CAI strength among the composite wound concrete cylinder is 4.81 times higher than that of the concrete cylinder without the reinforced composite. In addition, the former has higher failure strain than the latter. The impact resistance can be evaluated by a compression after impact/compression before impact (CAI/CBI) strength ratio. It is also detected that although impact damage has been introduced, the fracture of composite/concrete cylinder under compression may not be initiated from the impact site. Moreover, the failure strengths are influenced by damage mechanisms of the cylinders, and the damage modes for the concrete cylinder and wound composites are related. In this paper, the damage mechanisms of different wound concrete cylinders under CAI test were discussed.