Vacuum Bagging Method Research Articles

Thermal analysis of multi-walled carbon nanotubes doped glass fiber reinforced polymer composites

Thermal characterization is one of the important aspects for evaluating the heat flux and decomposition kinetics of different materials, alloys and composites at different temperature. In this work Multi-scale nano-composites (MWCNTs/glass fiber/epoxy) were prepared by hand lay-up process followed by vacuum bagging method. Thermal properties of MWCNTs doped glass fiber reinforced polymer composites were evaluated by differential scanning calorimetry (DSC), thermo gravimetric analysis (TGA) and differential thermal analysis (DTA). It has been found that in the presence of MWCNTs it is very difficult to break the polymeric chains and that leads to reduction in cross linking density and glass transition temperature of MWCNTs doped glass fiber reinforced polymer composites as compared to pristine one.

Flexural behaviour of jute, glass, and Carbon fibre reinforced Polyester hybrid composites

This study is a part of a project in developing natural fibre reinforced composite for wind turbine blade. The objective of this study is to evaluate the effect of fibre stacking sequence on flexural behaviour of the natural fibre reinforced composite hybridized with synthetic fibre. The flexural behaviour of the composite becomes an important consideration in deciding stacking sequence of the fibres. Material used in this study is polyester resin as the matrix. Jute, glass, and carbon fibres are used as the reinforcement. The composites were fabricated using vacuum bagging method cured at room temperature. The combinations of fibre as the reinforcement are configured by arrange two and three types of fibre. As a natural fibre, jute exists in all kind of combination. Flexural behaviour was observed using 3-point-bending test. The specimens were tested in accordance to the fibre stacking sequence. The result shows that stacking sequence of the fibres give significant different flexural behaviour regardless the effect of the fibre strength.

Effects of Bleeder Schedule to Fiber Mass Fraction and Composites Surface Topography on Wet Lay-up Manufacturing Process

The thermal protector materials of the rocket’s motor are made by a wet lay-up manufacturing process. Since the fiber mass fraction of the product is low, several experiments were conducted to solve this problem including changing the type of the epoxy resin and selecting the most suitable bleeder schedule. Bleeder cloth application results in increasing the fiber mass fraction. The fiber mass fraction of thermal protector material manufactured by hand lay-up can reach a maximum of 56,78%, whereas vacuum bagging can reach a maximum of 66,43%. Peel ply and breather fabric combination are the best bleeder schedule for the hand lay-up method meanwhile perforated release film and breather fabric are the best bleeders for the vacuum bagging method. Composite surface topography obtained from peel ply is visible on the surface. The imprints of the nylon peel ply weave are visible through SEM analysis. Meanwhile, the surface topography obtained from the perforated release film is not visible. The vacuum bagging method helped reduce the number of voids and ductile polymer fractures from the composite surface. This paper recommends peel ply usage in the thermal protector manufacturing process to replace the sanding or filling method that the author use nowadays.

Properties Comparison of Open Hole and Non-Hole Carbon UD-Lycal Composite with Vacuum Bagging Manufacturing Method

Carbon fiber reinforce polymer is one of some composite materials that has the high strength with light weight material. To apply this composite to the amphibious airplane structure, it should through the experimental tensile test to know the tensile strength and modulus of elasticity of the composite. In this experiment, we use Carbon UD fiber and Lycal resin as the composite material that manufactured with Vacuum Bagging Method. Specimens and testing process refer to ASTM D3039 for non-hole specimen, and ASTM D5766 for open hole specimen of tensile test standard for composite matrix polymers. The result of the experimental test shows that the tensile modulus of elasticity for non-hole composite is 34.92 ± 0.13 GPa, with the Ultimate Tensile Strength of this composite is 1081± 0.03 MPa, and the modulus of elasticity for open hole composite is 41.87± 0.02 GPa, with the Ultimate Tensile Strength of this composite is 899.04± 0.02 MPa. The simulation yields nearly same stress-strain graph with the result of experiment. The result shows that, the open hole composite has the ultimate tensile strength lower than non-hole composite, it’s due to the open hole composite has a trigger failure that may decreasing the tensile strength value.

Mechanical Properties of Composites Reinforced with Technical Embroidery Made of Flax Fibers

Abstract The main purpose of the article is to present the new possibilities of producing composite reinforcement with the use of a computer embroidery machine. This kind of production is in line with the principles of sustainable development. The study below presents the results of strength tests of composites containing sevenfold embroidery systems. Each variant included different directions of arrangement of individual layers as a reinforcement. Flax roving was used to strengthen the composite. Flax fibers are characterized by the highest strength among all-natural fibers, at the level of 50–80 cN/tex. The composite was made using the vacuum bag method, using epoxy resin. The embroidery was made on a ZSK embroidery machine, type JCZA 0109-550. The test material was subjected to strength tests—tensile strength, tensile elongation, and bending strength, on the INSTRON machine. Based on the research, it can be concluded that the arrangement of the roving in the direction of the tensile force allowed to obtain the best mechanical properties.

The effect of hexagonal nano boron nitride on mechanical performances and machinability behaviors of basalt fabric reinforced epoxy composites

The aim of this work is to investigate the effect of the hexagonal nano boron nitride (h-BN) doped epoxy on the mechanical performances and machinability behaviors of basalt fiber (BF) composites. The h-BN has used as a dopant with a weight rate of 1 wt. %. The polymer composites were prepared by the vacuum bagging method and specimens were processed with abrasive water jet machining (AWJM) to analyze the machinability of the material. A circular hole with an 8 mm size was machined by abrasive water jet (AWJ) on the composite plate with a thickness of 2.3 ± 0.1 mm using the garnet size of 80 µm as an abrasive. Taper angle and circularity of machined hole, the entry-exit hole diameter, delamination, splintering, burring, thickness, and hardness were measured. Results indicate that cutting speed has a high influence on the taper angle and circularity respectively.

Effect of graphite particulate on mechanical characterization of hybrid polymer composites

Quest for producing lightweight and biodegradable materials has encouraged researchers to replace synthetic fibers with natural fibers. Hence a study is made to investigate the effects of introducing secondary reinforcement (natural fibers), stacking sequence, and addition of graphite particles on the mechanical characteristics and water uptakes along with diffusivity of hybrid (glass\jute) composites. Different weight fractions of graphite particulates are incorporated into the epoxy to produce different samples having 4 plies for each sample by hand layup vacuum bagging method. The obtained specimens are subjected to various mechanical tests, water absorption tests as per the ASTM standards, and optical microscopy was used to study the fracture morphology of the samples. The results displayed that the properties are deteriorated a little with the addition of secondary reinforcement, however they have improved with the addition of graphite. E-Glass as skin layer and treated jute as core layer composite exhibits ameliorate tensile strength (201.5 MPa), compression strength (515.12 MPa), flexural strength (106.9 MPa), hardness (25 BHN). However highest impact energy of 26 J is recorded for the sample with jute as skin layer and E-Glass as the core layer. Water absorption tests revealed that the addition of graphite has reduced the water absorption in the hybrid samples.

The effect of boron carbide additive on the low‐velocity impact properties of low‐density foam core composite sandwich structures

AbstractSandwich structures with carbon fiber‐epoxy face sheets and polyvinyl chloride foam core material are known for their high strength and flexural stiffness despite their low weight. However, the structural response, in terms of crush strength, of the particles added sandwich structures are not very well known under impact loading conditions. In this study, the impact resistance and damage characteristics of particle added low weight composite sandwich structures were investigated with a low‐velocity drop weight impact test device. Boron carbide (B4C) particles, which had excellent hardness, thermoelectric, and radiation absorbing characteristics, were used as an additive for the epoxy matrix. For this purpose, 2%, 5%, and 10% by weight additives were mixed into the epoxy matrix and sandwich structures were produced with hand lay‐up followed by vacuum bagging method. All configurations were subjected to low‐velocity drop weight impact test at three different energy levels (10, 17.50, and 25 J). The results obtained from the experiments and the images of the post‐impact damage of the sandwich structures were presented comparatively. According to the test results, configurations containing 10% boron carbide (B4C) additive has shown the best performance in terms of resistance to impact load.

A Preliminary Study of the Influence of Graphene Nanoplatelet Specific Surface Area on the Interlaminar Fracture Properties of Carbon Fiber/Epoxy Composites.

Graphene nanoplatelets (GNPs) are of particular interest to the field of nano-reinforced composites since they possess superior mechanical, fracture, thermal, and barrier properties. Due to their geometrical characteristics, high aspect ratio (AR)/specific surface area (SSA) and their planar structure, GNPs are considered as high-potential nanosized fillers for improving performance of composites. The present study investigates the effect of SSA of GNPs on fracture properties of carbon fiber reinforced polymers (CFRPs). For this reason, two nano-doped CFRPs were produced by using two types of GNPs (C300 and C500) with different SSAs, 300 and 500 m2/g, respectively. Both types of GNPs, at the same content of 0.5 wt%, were added into the epoxy matrix of composites by applying a three-roll milling technique. The nanomodified matrix was used for the manufacturing of prepregs, while the final composite laminates were fabricated through the vacuum-bag method. Mode I and II interlaminar fracture tests were carried out to determine the interlaminar fracture toughness GIC and GIIC of the composites, respectively. According to the results, the toughening effect of C500 GNPs was the strongest, resulting in increases of 25% in GIC and 33% in GIIC compared with the corresponding unmodified composites. The activation of the absorption mechanisms of C500 contributed to this outcome, which was confirmed by the scanning electron microscopy (SEM) analyses conducted in the fracture surfaces of specimens. On the other hand, C300 GNPs, due to disability to be dispersed uniformly into the epoxy matrix, did not influence the fracture properties of CFRPs, indicating that probably there is a threshold in SSA which is necessary to achieve for improving the fracture properties of CFRPs.

Fracture toughness of alumina filler filled glass fabric reinforced epoxy composites

Micron sized alumina particles (≤10 µm) are incorporated between the plies of a conventional glass fabric reinforced epoxy (GE) composite to improve the fracture toughness ( K IC ). The influence of the alumina filler content (0, 7.5, and 10 wt%) on K IC are investigated. These composites are prepared by hand layup assisted by the vacuum bagging method. The prepared composites are evaluated for K IC at room temperature, elevated temperature (100 °C) and at cryogenic temperature (−15 °C). The K IC test was conducted utilizing single notched edge bend specimen under mode I according to ASTM D5045 standard. The test results indicated that K IC of GE is improved by addition of alumina particles. Furthermore, these composites maintained higher K IC at −15 °C and decreased significantly at elevated temperature. The maximum K IC is recorded at particle loading of 10 wt% GE hybrid composite.

Graphene nanoplatelet modified basalt/epoxy multi-scale composites with improved tribological performance

The wear performance of non-toxic and respiratory non-hazardous natural fiber reinforced epoxy composites has steadily become an important design parameter due to their increasing applications in self‐lubricating and sliding components in contact with metal counterparts. Epoxy matrix has weak wear resistance, and reinforcing the matrix with nano-sized particles has been shown to improve the tribological performance of the resulting multi-scale composites. For this, the epoxy matrix was reinforced with various concentrations of GNPs, and the BF/EP composites were fabricated via the vacuum bagging method, subsequently. The tensile strength and modulus were enhanced up to 42.5 and 74.5% compared to the bare BF/EP laminates, respectively. Moreover, the ball-on-disk wear tests revealed that GNP reinforcement was reasonably effective in reducing the coefficient of friction (23%) in contact areas. As a result, GNP reinforced BF/EP composites exhibited 60% higher wear resistance. In addition to well-known solid lubricant characteristics of GNPs, thermal camera recordings were identified that the improved thermal conductivity in all directions was also responsible for the enhanced tribological performance. The microscopic studies identified the related micro-scale mechanisms responsible for the improved tribological performance of the multi-scale composites. We proposed a unique wear mechanism to represent the tribological behavior of the GNP reinforced BF/EP composites based on electron microscopy and thermal camera recordings.

Unhole and open hole tensile properties of hybrid Kevlar/glass fiber polymer composites with different stacking sequence

The effects of stacking sequence play a vital role in determining the mechanical properties of fiber-reinforced polymer composite materials. This study was conducted to investigate the effects of a hole and unhole Kevlar/glass fiber hybrid composite specimens at four different stacking sequences. Other than stacking sequence, the damage tolerance properties were also analyzed in this study to find out the strength reduction between the hole specimen and the unhole specimens. The damage fractured on the surface of the specimens was also analyzed through macroscopic observation and scanning electron microscope. All the specimens in this study were fabricated using vacuum bagging method according to the ASTM D5766 for open-hole tensile test. In the open-hole tensile test, unhole and hole hybrid composite specimen (H4) with alternate layered fiber, projected the highest value of tensile properties. The alternate layered fiber can improve the interlaminar adhesion; thus, increase the tensile strength as compared to the sandwich stacking sequence (H2 and H3). Based on this study, GFRP and hybrid composite specimens displayed approximately 40%-50% strength reduction, while KFRP recorded only 30% of strength reduction. From the damage observation, the failure characteristics change from fiber pull out in glass fiber composite to fiber breakage in Kevlar fiber composite specimens.

Alkali Treatment Influence on Characterization of Setaria Italic (Foxtail Millet) Fiber Reinforced Polymer Composites Using Vacuum Bagging

ABSTRACT Natural fiber polymer composites have broad interest in recent times due to low cost and superior mechanical properties. The present study deals with Setaria italic (Foxtail millet) fiber reinforced Lapox L-12 resin polymer composite fabricated by vacuum bagging method. The work examined the differences of NaOH alkali-treated (5% and 10% concentration) and untreated fibers with different weight ratios (10%, 15%, and 20%) of fibers. Mechanical properties of the prepared discrete polymer composite materials were analyzed. The alkali treatment behavior of Setaria italic fiber was analyzed using scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and Fourier transform infrared spectroscopy (FTIR). An increase in 35.1%, 8.6%, and 6% for tensile, flexural, and impact strength, respectively, were observed for 20 wt% reinforced composites with 10% NaOH treatment when compared to untreated composites. From TGA, it was concluded that residue content of the samples were observed to be 15%, 10%, and 7% for untreated, 5% NaOH-treated and 10% NaOH-treated samples, respectively. Based on the acquired results, it was concluded that alkali-treated Setaria italic (Foxtail millet) fiber reinforced epoxy composites can be a resourceful substitute in construction and building applications.

Optimization of drilling process parameters on delamination factor of Jute reinforced unsaturated polyester composite using Box-Behnken design of experiment

This paper presents an investigation on the influence of the drilling parameters such as feed rate, spindle speed and drill tool diameter onto the delamination factor of the jute reinforced unsaturated polyester composite. Natural fibre based composite are mostly used for commodity application and often subjected to drilling during applications and may generate delamination of drilled holes on the workpiece. The composite was fabricated using woven jute fibre via vacuum bagging method followed a high temperature curing using hot press. The fibre was kept at 40 vol. %. The main effect and the interaction between the specified factors of feed rate (20-100mm/min), spindle speed (500-1500 rpm) and drill tool diameter (4-8 mm) with delamination factor as corresponding respond was structured via the Response Surface Methodology (RSM) based on three-level Box-Behnken design of experiment and the ANOVA. The levels of importance of the process parameters on flexural properties are determined by using Analysis of Variance (ANOVA). The optimised drilling process parameters obtained as 24.38 mm/min of feed rate, 1146.14 rpm of spindle speed and 5.51 mm drill tool diameter achieved the most minimal delamination factor. The feed rate and spindle speed were perceived as the most influential drilling parameters on the delamination factor of the jute reinforced unsaturated polyester composite.

Enhancement of Impact Properties by Using Multiwall Carbon Nanotubes as Secondary Reinforcement in Glass/Epoxy Laminates

Abstract This study is focused on the drop weight low-velocity impact (LVI) response of glass woven polymer composite laminates reinforced with multiwall carbon nanotubes (MWCNTs). Symmetrical quasi-isotropic laminates with zero bending-extension coupling were fabricated. Six hundred-grams per square meter plain glass woven fabric was used as a primary reinforcing agent while MWCNTs were used as the secondary reinforcement. The exceptional mechanical properties of MWCNTs in the context of impact damage tolerance in fiber-reinforced polymer composite laminates were examined and the limitation of scattered data was overcome by doing a range analysis. MWCNT-doped glass fiber reinforced polymer (GFRP) laminates were fabricated in seven proportions (neat, 0.25, 0.5, 0.75, 1, 1.5, and 2 weight percentage of resins) by using the hand layup technique, followed by the vacuum bagging method at 1 atm. By mixing MWCNTs as a secondary reinforcement, the maximum enhancement of 32.6 % in energy absorption, 10.26 % in peak load capacity (at 3.0 m/s impact velocity), and 32.44 % reduction in the visual damage area was attained (at 3.5 m/s indentation). Experiment results (for neat GFRP) were also validated by using three-dimensional finite element analysis software LS-DYNA.

Morphology of Aluminum Oxide (Al₂O₃) Nanoparticles and Their Effect on the Micro Structural and Mechanical Properties of Carbon Fiber-Reinforced (CFR) Epoxy Nanocomposites

The main aim of this article is to investigate the effect of inclusion of Aluminum oxide (Al₂O₃) nano particles at varied percentage of weights into the carbon fiber-reinforced (CFR) epoxy composites, and evaluating the Mechanical properties for flexure, Impact and Tensile strength. The Aluminum oxide (Al₂O₃) is included into various percentages starting from 1 to 5 wt% and spread homogeneously throughout the epoxy resin by ultrasonication process. The CFR- Al₂O₃ nano composites are prepared through layup technique and healed by vacuum bagging method. The mechanical properties such for flexure and ultimate tensile strength showed better properties due to the presence of Al₂O₃ nanoparticles, while response for CFR- Al₂O₃ nano composites increased at 2 wt% addition of Al₂O₃ nano particles, and further reduction has been seen at 5wt% due to an greater static effect.

Influence of titanium oxide fillers on the tensile and flexural properties of E-glass fabric/epoxy composites

In present scenario E-Glass fabric polymer is playing a major role in the field of structural and aerospace. The elemental composition of filler materials and its size of particles play a vital role in the development of mechanical and physical characteristics of micro filler integrated polymer matrix composites. In this paper E- glass fabric/epoxy composite materials are modified by adding the combination of Titanium oxide (TiO2) and amine terminated butadiene acrylonitrile (ATBN) to improve the mechanical properties. Vacuum bagging method is employed to develop the polymer matrix composites and the composites are experienced underneath tensile and flexural test at room temperature in order to scrutinize the strength. Scanning electron microscopy analysis used to identify the mode of failure of the composite, debonding and pull out of fiber is observed in the composites. Agglomeration of micro filler materials in the matrix is observed in scanning electron microscopy images which reveal micro structural information of fractured surfaces of composites. The mechanical characterization results showed that the tensile and flexural strength of developed composites are comparable to the strength of the E-glass fabric.

Influence of fly ash nano filler on the tensile and flexural properties of novel hybrid epoxy nano-composites

In this research work, the influence of nano-fly ash as filler material on tensile and flexural properties of epoxy/Basalt (B)/Jute (J)/Banana (B)/Carbon (C) laminated was studied. The hybrid composites laminates are fabricated by the vacuum bagging method increase the tensile and flexural Properties the main application of these research work are aerospace, defence, and automobile application increasing demand for unique material produce innovation synthetic and natural fabric reinforced composite are replacing conventional materials as natural fabric is low cost, biodegradable and economical density in the hybrid composites are fabricated with jute, carbon, basalt, and banana reinforced plastics with LY 556 epoxy resin as matrix. The tensile and flexural strength of the LY 556 epoxy resin/hybrid laminates were increased profoundly in the presence of Nano fly ash. The epoxy + BJBC + 4 wt% Nano-Fly ash composites showed better tensile and flexural results when compared with the epoxy + BJBC fiber composites. Nano-scale particles are currently considered to be potential filler material for improving properties of existing composite material due to nanotechnology. The polymer composite has become more attractive. Nanofiller, which are an industrial waste popularly recognize as environmental pollution as many potentials such as silicon oxide and aluminium oxide. As the ecological problems presented by Nano filler, considerable research has been undertaken on the subject worldwide. It was also found that Nano fly ash as filler-added composites shows better results when compared with and without filler-added composites. It is use as a cheap adsorbent for the removal of organic compounds, lightweight aggregate and building construction material. However, very little is reported on its potential as nonmaterial nano fly ash as filler in thermo-set polymer composites.

Effect of the Recyclate on a Deflection of Composites in Bending

Abstract The aim of the research was to determine the effect of polyester-glass recyclate on the deflection of composite samples subjected to three-point bending. The polyester-glass recyclate was obtained from the part of the ship’s hull made of polyester-glass composite, constituting scrap metal. The pieces of scrap were pre-fragmented and then processed into a prepared stand for this purpose. Such a fragmented recycling will be used to make composites with different scrap / recycled content. For this purpose, research materials were made using the vacuum bag method with the percentage of 0%, 10% and 20% recyclate) as well as various granulation (i.e. 1.2 mm and 3.0 mm). The research material consisted of rectangular plates with a thickness corresponding to the thickness of the samples. The samples for testing were made by water cutting. The tests were carried out on a suitably prepared stand, which was made of a universal Zwick Roell testing machine and three-point bending handles and a dial indicator. The spacing of the supports has been determined in accordance with the binding standard for three-point bending. Obtained results from tests, i.e. strain, stress, deflection, deformation allowed analysing the impact of recyclate on bending strength and defining the deflection arrow. Based on the results obtained from three-point bending, it can be concluded that the polyester-glass recycling has an influence on the decrease of strength, stress and deflections of the tested composites.

The Application of Empty Palm Fruit Bunch (EPFB) As a Material for Fixed Wing Type Unmanned Aerial Vehicle Fuselage Production

One of a potential application of Empty Palm Fruit Bunch (EPFB) is the material of fuselage on Unmanned Aerial Vehicle (UAV). This study was began by Alkali Treatment on EPFB. Then, the fuselage was molded using Vacuum Bagging Method. There are three unit of mold with combination of fiberglass + carbon fiber, fiberglass + EPFB fiber and full EPFB fiber. The measurement show fuselage with hybrid composite material (fiberglass and EPFB) has the lightest mass of 559 gram. Deflection Test of all three fuselages show that the maximum deflections were under 1 mm. Next, the Static Impact Test show no damages or cracks on all three fuselages. The result of Flight Test show all fuselages could do well fly and survive belly landing.