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Fixed-wing unmanned aerial vehicles are a type of drone that uses rigid wings, similar to those of an airplane, to generate lift. The wings are the most critical component of the aircraft. The wing structure must be designed to withstand the lift generated, therefore the wing structural strength analysis is required before the wing manufacturing process begins. This paper presents the analysis and construction of a VTOL UAV using the NACA 651-421 airfoil on a wing structure made of composite materials. A finite element model method using Abaqus software to predicts the maximum stress, displacement and failure index with two vertical take off and cruise simulation conditions. The process manufacturing wing structure by using vacuum bag laminating method. Most of the wing structure composite materials consists of E-glass and Carbon fibers. In the results, then the maximum stress, displacement, and failure index are obtained with the highest value in a maximum stress, displacement, and failure index with the highest value is in cruise condition, which is used as a reference parameter in the manufacture of the wing structures and besides that, it must also meet the maximum take-off weight of the UAV wing structure.

Fibre-reinforced polymers (FRP) have attracted much interest within many industrial fields where the use of 3D printed molds can provide significant cost and time savings in the production of composite tooling. Within this paper, a novel method for the manufacture of complex-shaped FRP parts has been proposed. This paper features a new design of bike saddle, which was manufactured through the use of molds created by fused deposition modeling (FDM), of which two 3D printable materials were selected, polylactic acid (PLA) and acrylonitrile butadiene styrene (ABS), and these molds were then chemically and thermally treated. The novel bike saddles were fabricated using carbon fiber-reinforced polymer (CFRP), by vacuum bag technology and oven curing, utilizing additive manufactured (AM) molds. Following manufacture the molded parts were subjected to a quality inspection, using non-contact three-dimensional (3D) scanning techniques, where the results were then statistically analyzed. The statistically analyzed results state that the main deviations between the CAD model and the manufactured CFRP parts were within the range of ±1 mm. Additionally, the weight of the upper part of the saddles was found to be 42 grams. The novel method is primarily intended to be used for customized products using CFRPs.

Tribo-mechanical experiments were performed on Glass Fiber Reinforced Polymer (GRFP) composites against different engineering materials, and the tribological behavior of these materials under dry conditions was investigated. The novelty of this study consists of the investigation of the tribomechanical properties of a customized GFRP/epoxy composite, different from those identified in the literature. The investigated material in the work is composed of 270 g/m2 fiberglass twill fabric/epoxy matrix. It was manufactured by the vacuum bag method and autoclave curing procedure. The goal was to define the tribo-mechanical characteristics of a 68.5% weight fraction ratio (wf) of GFRP composites in relation to the different categories of plastic materials, alloyed steel, and technical ceramics. The properties of the material, including ultimate tensile strength, Young’s modulus of elasticity, elastic strain, and impact strength of the GFPR, were determined through standard tests. The friction coefficients were obtained using a modified pin-on-disc tribometer using sliding speeds ranging from 0.1 to 0.36 m s−1, load 20 N, and different counter face balls from Polytetrafluoroethylene (PTFE), Polyamide (Torlon), 52,100 Chrome Alloy Steel, 440 Stainless Steel, and Ceramic Al2O3, with 12.7 mm in diameter, in dry conditions. These are commonly used as ball and roller bearings in industry and for a variety of automotive applications. To evaluate the wear mechanisms, the worm surfaces were examined and investigated by a Nano Focus—Optical 3D Microscopy, which uses cutting-edge μsurf technology to provide highly accurate 3D measurements of surfaces. The obtained results constitute an important database for the tribo-mechanical behavior of this engineering GFRP composite material.

To design a new breast vacuum bag to reduce global and local setup errors in post-mastectomy radiation therapy (PMRT). A total of 24 PMRT patients were immobilized with an old vacuum bag and 26 PMRT patients were immobilized with a new vacuum bag. The registration results were analysed using four regions of interest (ROI): the global ROI [including the whole region of the planning target volume (PTV), GROI], the supraclavicular area (SROI), the ipsilateral chest wall region (CROI) and the ipsilateral arm region (AROI). The global and local setup errors of the two groups were compared. The global setup errors of the new vacuum group were significantly smaller than those in the old vacuum group with the exception of yaw axes (P < 0.05). The systematic error (Σ) and random error (σ) ranged from 1.21 to 2.13 mm. In the new vacuum group, the local setup errors in the medial-lateral (ML) direction and roll axes for CROI (the Σ and σ ranged from 0.65 to 1.35 mm), and the local setup errors in ML and superior-inferior (SI) directions for SROI were significantly smaller than those in the old vacuum group. The total required PTV margins for the chest wall in ML, SI, and anterior-posterior (AP) were 4.40, 3.12 and 3.77 mm respectively. The new vacuum bag can significantly reduce the global setup errors and local setup errors in PMRT. The respiratory motion of the chest wall was negligible, and the 5 mm PTV margin could cover the local setup errors in PMRT using the new vacuum bag with cone beam CT (CBCT) correction.

Nanocomposite laminates containing carbon fibers, epoxy, and multiwalled carbon nanotubes were fabricated using a vacuum bag process. Ecofriendly ionic liquid (5 wt%)-treated multiwalled carbon nanotubes (pristine and nickel-coated) were added to the epoxy independently, in amounts ranging from 1 wt% to 3 wt%, in order to tailor the mechanical, electrical, and thermal performance of manufactured carbon fiber epoxy composite laminates. These nanocomposite laminates were later characterized through flexural testing, dynamic mechanical analysis, impedance spectroscopy, thermal conductivity tests, and FTIR spectroscopy to evaluate their suitability for battery pack applications. The findings showed that both types of multiwalled carbon nanotubes exhibited multifaceted effects on the properties of bulk hybrid carbon fiber epoxy nanocomposite laminates. For instance, the flexural strength of the composites containing 3.0 wt% of ionic liquid-treated pristine multiwalled carbon nanotubes reached 802.8 MPa, the flexural modulus was 88.21 GPa, and the storage modulus was 18.2 GPa, while the loss modulus peaked at 1.76 GPa. The thermal conductivity of the composites ranged from 0.38869 W/(m · K) to 0.69772 W/(m · K), and the electrical resistance decreased significantly with the addition of MWCNTs, reaching a minimum of 29.89 Ω for CFRPIP-1.5 wt%. The structural performance of hybrid nanocomposites containing ionic liquid-treated pristine multiwalled carbon nanotubes was higher than that of the hybrid nanocomposite of ionic liquid-treated Ni-coated multiwalled carbon nanotubes, although the latter was found to possess better functional performance.

Modification of the properties of GFRP composites is mostly done because of its wide application, one of which is to increase its thermal resistance properties. Adding clay as a filler can increase flame retardant but affects changing mechanical properties. Clay mixed with resin with a magnetic stirrer with speed and mixing time parameters was studied to see the effect on changes in mechanical properties (flexural, tensile, and impact) which were analyzed using the CCD method. Variations of clay 1, 2, and 3% with stirring speeds of 100, 150, and 200 rpm and mixing times of 60, 90, and 120 min resulted in changes in flexural strength and modulus between −12 and 8% and −10% to 15% compared to pure resin. The highest increase in flexural strength and modulus occurred with the addition of 1% clay stirred at 200 rpm for 60 min was 306 MPa and 12,055 MPa. The same trend also occurs in Tensile strength and modulus, with the highest being 193 MPa and 6,258 MPa and the highest impact being 153 kJ/m 2 . The maximum strength and modulus were produced at low clay level, high mixing speed, and short mixing time. Maximum mechanical properties are produced at low clay content, high mixing speed, and short mixing time. High shear resulting from rapid stirring causes the clay to split and spread so that clay agglomeration does not occur. Short stirring time reduces the evaporation of the styrene so that more crosslinking occurs. Clay has a maximum function as a filler because of low agglomeration and there is a lot of crosslinking causing better mechanical properties.

Air removal prior to cure is critical for limiting porosity during vacuum bag-only (VBO) processing of prepregs. In this study, the effects of pre-cure dwell temperature (debulk) on air evacuation were investigated for both plain weave (PW) and unidirectional (UD) prepregs. In situ observations revealed that increasing dwell temperature promoted inter-ply air evacuation (by as much as 2x for UD prepregs). Through-thickness gas permeability increased with increasing temperature and decreased with increasing number of plies. The decrease in in-plane permeability during heated debulk was attributed to increased tow impregnation. The findings provide guidelines for cure cycle optimization. Heated debulk enhanced air evacuation in PW laminates, particularly as laminate width/thickness ratios exceed a threshold value. However, warm debulks were less effective, particularly for thicker laminates (>8 plies).

This paper presents the synthesis and mechanical characterization of hybrid polymer composites reinforced with sisal and corn husk fibres using vacuum bag moulding. The selection of these natural fibres was guided by their availability, low cost, and biodegradability. Composite specimens were fabricated with fibre weight fractions of 5%, 10%, 15%, 20%, and 25%, employing epoxy resin as the matrix material. Mechanical tests including tensile, flexural, impact, and wear evaluations were conducted. The tensile strength increased from 32 MPa to 45 MPa, while the tensile modulus rose from 2.5 GPa to 3.5 GPa with increasing fibre content. Similarly, flexural strength improved from 60 MPa to 85 MPa, and the flexural modulus from 3.0 GPa to 4.0 GPa. Wear rate decreased from 0.8 mm 3 /Nm to 0.3 mm 3 /Nm, and both impact resistance and energy absorption capacity increased from 15 J to 35 J. SEM analysis revealed uniform fibre dispersion and strong interfacial bonding between the fibres and the matrix. These enhancements in mechanical performance indicate that the developed composites are environmentally friendly alternatives to conventional synthetic composites, with potential applications in construction, automotive panels, and sports equipment.

Polymer composite products can be obtained by primary manufacturing processes such as contact molding, vacuum bag molding, resin transfer molding, or sheet molding compound and secondary processes such as drilling and saw cutting. Drilling is generally employed to make bolted or riveted assembles in composite structures. In drilling, some defects like delamination and crack are seen, and also undesired hole surface roughness related to tool wear is an another problem frequently encountered. In this study, tool wear in drilling of sheet molding compound (SMC) composite, consisted of 30 wt.% glass fiber, 25 wt.% polyester, and 45 wt.% calcium carbonate, was investigated. SMC composite was drilled under different cutting speeds, feeds, and drill point angles. Taguchi design of experiments and analysis of variance were utilized to determine the optimal cutting parameters and to analyze the effects of them on the tool wear. The feed followed by the drill point angle were found to be the important factors while cutting speed was the least effective parameter. Chip volume was accepted as a criterion to compare obtained data. Increasing feed and decreasing drill point angle reduced the tool wear. Multivariable linear regression analysis was also employed to determine the correlations between the factors and the tool wear. Finally, a model was generated and a good approximation was achieved in the comparison of the experimental data and the predicted data obtained from the model.

There are a slew of elements at work in the composites sector, from people and markets to technology and innovation, that are continually reshaping the industry's structure. For now, composite materials' winning combination of high strength-to-weight ratio continues to propel them into new areas, but other attributes are just as crucial. These properties, which may be customized for unique purposes, result in a completed product requiring fewer raw materials and fewer joints and fasteners, as well as reduced assembly times, thanks to composite materials. To lower product lifespan costs, composites also have demonstrated resilience in industrial applications to temperature extremes as well as corrosion and wear. Polymers, ceramics, and metals can all be used as matrices. Thermoplastic (TP) resin is the second most prevalent matrix type, and it is becoming increasingly popular among composite makers. By melting or softening and then chilling the material, thermoplastic linear polymer chains are generated and may be reformed into shaped solids. It is common for thermoplastics to be offered in sheet or panel form, which may be treated using in situ consolidation processes, such as pressing, to manufacture durable, near-net-shape components without the need for an autoclave or vacuum bag cure. Correcting abnormalities or fixing harm done in service is possible with reformability.