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This article researches a superhydrophobic anti‐fouling material that can be used for agricultural medicine boxes, aiming to solve the problems of residual medicine, difficult recovery, and low reuse rate in medicine boxes. Double modification (volume and surface modification) is carried out on the ultra‐high molecular weight polyethylene (UHMWPE) matrix, and the high fluidity of melted snow wax is connected to UHMWPE and gas‐phase silica (SiO2) to prepare superhydrophobic composite materials U‐C‐WSiO2, achieving multiple combinations of superhydrophobicity, high mechanical properties, and high stability. The high‐strength bonding between snow wax and UHMWPE matrix acts as an adhesive, strengthening the bonding degree between silica particles and the matrix, achieving excellent superhydrophobicity, static contact angle reaches 157.0° on its surface while maintaining a relatively stable hydrophobic surface after multiple droplet impacts. In addition, unique surface modification methods endow U‐C‐WSiO2 composite materials with high stability, which can resist pesticide erosion and maintain surface corrosion resistance. This superhydrophobic composite material can solve the problem of pesticide residue in medicine boxes and has broad prospects for agricultural applications. Its surface water repellent and drug repellent properties further expand the application of thermoplastic engineering plastics in agricultural production. [ABSTRACT FROM AUTHOR]

It is a known fact that aerospace industry requires very strict requirements in terms of weight, material properties, and product lifetime performance. Therefore, composite materials are key candidates to satisfy these stringent requirements. Thermoplastic composites have become more competitive in the fields of aerospace, defense, energy, electronics, and automotive industries compared to thermoset composites, due to their ease of formability, short production cycles, and recyclability. Considering the benefits of thermoplastic composite materials, more thermoplastic parts will be produced in near future in aerospace industry. This study highlights the most recent advancements in thermoplastic composite technology. The latest advances in thermoplastic composite technology are highlighted by reviewing material technologies and production methods. Conclusion of this study, it has been observed that the use of thermoplastics in the aerospace industry is increasing day by day, owing to the advantages they offer compared to traditional materials. Especially in critical and trending areas such as stamp forming, press consolidation, Automatic Fiber Placement (AFP), and welding methods, research and development activities are intensifying. Furthermore, this study provides insights into the direction of current investments in thermoplastic technology and discusses how these investments are likely to shape future applications within the aerospace industry. [ABSTRACT FROM AUTHOR]

Polyaryletherketone (PAEK) thermoplastic composite materials have received increasing attention for the manufacturing of composite structures. One manufacturing process of great interest for PAEK composite structures is automated fiber placement, which can increase the throughput of complex part fabrication and reduce the use of autoclaves for assembly of composite parts. Understanding the thermal effects of the material allows the control and adjustment of manufacturing variables to assure the integrity of the composite structure. PAEK resins and carbon fiber reinforced composites have been analyzed using differential scanning calorimetry to study crystallization kinetics. Isothermal and non‐isothermal tests were conducted, and the time‐dependent crystallization kinetics were modeled using the Velisaris and Seferis model for isothermal processes and the Gaussian process regression method for non‐isothermal processes. The results show the influence of the thermal conditions and the chemical structures considering the ketone content, and the effects of the presence of the carbon fibers on crystallization kinetics. The models utilized describe with high accuracy the time‐dependent crystallization kinetics of PAEK composite materials. An artificial neural network application was also implemented using the non‐isothermal PAEK composite models for further prediction of relative volume crystallinity and crystallization rate. Highlights: Polyaryletherketone (PAEK) materials crystallize differently depending on the crystallization conditions.Carbon fibers influence the crystallization response in PAEK polymers.Machine learning was used to characterize crystallization kinetics.Activation energies were obtained for different thermal treatments.Artificial neural network tool was developed for PAEK composites in non‐isothermal regimes. [ABSTRACT FROM AUTHOR]

The application of polymer composites is one of the most effective methods for preventing lubrication failure in deep‐sea engineering. In this study, fluorinated graphite (FGr) microsheets were incorporated into polytetrafluoroethylene (PTFE) microparticle‐filled poly(butylene terephthalate) (PBT) composites. The tribological performance in the simulated deep‐sea environment at elevated seawater pressure equivalent to 3000 m ocean depth was investigated. The results showed that FGr enhances the flexural and compressive strengths, thermal stability, and seawater resistance of the PTFE/PBT composite. The wear rate was decreased to 96% at the critical FGr content of 4% by improving the transfer onto the metallic counterfaces, preventing direct contact and shear between friction couples. Moreover, the seawater pressure impedes composite transfer, leading to a 29% increase in the wear rate. [ABSTRACT FROM AUTHOR]

Composites based on polysulfone materials filled with various types of graphite and carbon black were studied and a solution technique was used to create composite materials with filling degrees ranging from 30 to 70% by weight. High filling levels with graphite fillers enabled thermal conductivity of 17.4 W/m·K to be achieved. The addition of carbon black as a filler to the composite helped to improve its mechanical characteristics, and its influence on electrical and thermal conductivity has also been explored. Natural graphite provides the best effect on composite thermal and electrical properties, whereas using artificial graphite allows to improve the mechanical behavior of composites. The relationship between sample density, porosity, and composition, as well as the effect of these factors on composite conductivity, has been studied and addressed. [ABSTRACT FROM AUTHOR]

This research investigates the durability of large-format 3D-printed thermoplastic composite material systems under environmental exposure conditions of moisture and freeze–thaw. Durability was evaluated for two bio-based composite material systems, namely wood-fiber-reinforced semi-crystalline polylactic acid (WF/PLA) and wood-fiber-reinforced amorphous polylactic acid (WF/aPLA), and one conventionally used synthetic material system, namely short-carbon-fiber-reinforced acrylonitrile butadiene styrene (CF/ABS). The moisture absorption, coefficient of moisture expansion, and reduction of relevant mechanical properties—flexural strength and flexural modulus—after accelerated exposure were experimentally characterized. The results showed that the large-format 3D-printed parts made from bio-based thermoplastic polymer composites, compared to conventional polymer composites, were more susceptible to moisture and freeze–thaw exposure, with higher moisture absorption and greater reductions in mechanical properties. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA) is the most widely used material in the fused filament fabrication (FFF) technique, which is a biocompatible thermoplastic. However, PLA's usefulness is limited by its narrow processing window and relatively low mechanical properties. Therefore, PLA composites have been developed to enhance its properties for FFF printing. A key challenge in producing composite parts via this method is to find the correlation between the mechanical properties of the parts and the process parameters. This knowledge is essential for optimizing the printing process to achieve the desired mechanical properties for composite parts industries such as aerospace, automotive, and medical, where high‐performance composite materials are crucial. The ability to control and predict the mechanical properties of FFF‐printed composite parts is critical for their successful integration into these industries. In this study, the effect of nozzle temperature (NT), printing speed (PS), and nominal porosity (POR) on the impact strength and specific impact strength of PLA/iron composites was examined using FFF. Response surface methodology (RSM) was used to optimize the experimental design. The results revealed that POR had the most significant effect on the impact resistance data, while NT had the least effect. Reducing the POR led to improved impact resistance in the samples. Multi‐objective optimization results showed that the lowest NT (190°C), the lowest POR (30%), and a PS of 50 mm/s were the optimal conditions for multiple objectives. RSM was also utilized to develop mathematical models of impact properties, focusing on varying NT, POR, and PS, which can be used to predict desired impact properties. Highlights: Nominal porosity has the most influence on the impact strength of PLA/iron composites.Optimum values were temperature of 190°C, nominal porosity of 30%, and speed of 50 mm/s.RSM was effective in enhancing the mechanical properties of composite materials.RSM models provide a predictive tool for future FFF‐printed composite parts.Maximum impact strength of 4.44 kJ/m2 was achieved. [ABSTRACT FROM AUTHOR]

The 3D printing of composite materials especially, nanocomposites, is an essential step in exploring new perspectives for the applications of organic matrix composite materials for industrial applications. In this work, the effect of ceramic nanofillers on the mechanical properties of a thermoplastic matrix is studied using different wt% of nanofillers (AEROSIL). The results showed that the increase in the wt% of AEROSIL resulted in an increase in the mechanical properties in terms of hardness, stiffness, ductility, and tensile strength. Moreover, these samples were 3D printed and were compared with the samples prepared by conventional injection moulding. The comparison characterized the influence of the manufacturing method on the mechanical performance of materials. Although there was very little behavior difference in both samples, the 3D-printed samples showed a weight reduction. This has broadened the possible applications of this material and technique in areas where weight is of utmost significance. [ABSTRACT FROM AUTHOR]

In this paper, the damage initiation/propagation mechanisms and failure modes of open-hole carbon fiber-reinforced thermoplastic composites and thermosetting composites with tension, compression, and bearing loads are investigated, respectively, by experiments and finite element simulations. The experimental evaluations are performed on the specimens using the Combined Loading Compression (CLC) test method, the tensile test method, and the single-shear test method. The differences in macroscopic damage initiation, evolution mode, and damage characteristics between thermoplastic composite materials and thermosetting composite material open-hole structures are obtained and analyzed under compressive load. Based on scanning electron microscope SEM images, a comparative analysis is conducted on the micro-failure modes of fibers, matrices, and fiber/matrix interfaces in the open-hole structures of thermoplastic and thermosetting composites under compressive load. The differences between thermoplastic and thermosetting composites were analyzed from the micro-failure mechanism. Finally, based on continuum damage mechanics (CDM), a damage model is also developed for predicting the initiation and propagation of damage in thermoplastic composites. The model, which can capture fiber breakage and matrix crack, as well as the nonlinear response, is used to conduct virtual compression tests, tensile test, and single-shear test, respectively. Numerical simulation results are compared with the extracted experimental results. The displacement-load curve and failure modes match the experimental result, which indicates that the finite element model has good reliability. [ABSTRACT FROM AUTHOR]

This study explores the use of α‐1,3‐glucan, which can be produced through an enzymatic polymerization process, as additive for thermoplastic polyurethane composite systems. Most importantly, highly filled thermoplastic polyurethane composites can be achieved with up to 80% by weight polysaccharide content. Analysis of mechanical properties demonstrates that strength and modulus can be significantly improved, while the plasticizer content allows for adjustments of compound flexibility. The addition of 60% α‐1,3‐glucan increased the flexural modulus of the thermoplastic polyurethane by 497% while adding 80% α‐1,3‐glucan increased the flexural modulus by 3193%. Citrate esters can be incorporated as plasticizer to improve processibility and flexibility of the compounds. An increase in impact strength of 55% was achieved when 10% of tributyl citrate was added to the 80% α‐1,3‐glucan composite. Based on the compatibility and property enhancements, the use of these engineered polysaccharides may provide additional options for producing sustainable composite materials with high renewable content and unique properties. [ABSTRACT FROM AUTHOR]

Some of the material demands in the advanced industries cannot be fulfilled by monolithic materials. Therefore, composite materials have been developed. The combination of desired properties of thermoplastics and glass particles (high strength and high modulus) is the aim of composites production Particles are becoming increasingly popular reinforcing elements in products made by injection molding. Particles reinforcement allows the polymer to be processed employing the same methods as those used for unreinforced polymers. The loads are not directly applied to the reinforcements, but they are applied to the matrix and some of the loads applied are transferred to the particles. The development of micromechanics equations for the particulate composites follows along the same lines as those for the short fiber reinforced composites. Particles are used to increase the strength or other properties of inexpensive materials during reinforcement with other matrix materials. The objective of this study is to analyse the particle breaking effect in composite made of nylon 66 (PA) matrix reinforced with glass particles, in which the particles diameters of 19.61, 26.15, 39.22 and 78.45 μm were used. A volume fraction of 20 % was assumed in each model. [ABSTRACT FROM AUTHOR]

Composite materials have found widespread applications in the automotive, aerospace, and building industries. Several components are joined together for these applications, by some temporary or permanent bonding approach. The increased use of different materials and their combinations such as composites makes the whole joining process something to be thoroughly considered before continuing. Several aspects need to be studied before spending significant time and financial resources. Considering these challenges in this paper we have provided a review of the investigations that have been made on fiber-reinforced composite joints. The level of development in various types of joints and joining techniques such as mechanical bonding, adhesive bonding, and fusion bonding along with their advantages and disadvantages is given. Several parameters affecting the performance of composite joints such as joint configuration, material selection and properties, geometric parameters, dominating failure modes, and environmental factors are described briefly. To verify the performance of composite joints, guidance on joint testing is given (both destructive and non-destructive). [ABSTRACT FROM AUTHOR]

Among the various welding techniques used to bond thermoplastic composites, induction welding stands out as a fast, clean, and contact-free process that shortens the welding time and prevents the weight increase of mechanical fastening, such as rivets and bolts. In this study, we manufactured polyetheretherketone (PEEK)-resin-based thermoplastic carbon fiber (CF) composite materials at different automated fiber placement laser powers (3569, 4576, and 5034 W) and investigated their bonding and mechanical characteristics after induction welding. The quality of the composite was evaluating using various techniques, including optical microscopy, C-scanning, and mechanical strength measurements, and a thermal imaging camera was used to monitor the surface temperature of the specimen during its processing. The results revealed that the preparation conditions of the polymer/carbon fiber composites, such as the laser power and surface temperature, significantly affect the quality and performance of the induction-welding-bonded composites. A lower laser power during preparation resulted in weaker bonding between components of the composite and yielded samples with a lower shear stress. [ABSTRACT FROM AUTHOR]

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Additive manufacturing of composite materials is a promising technology. It could solve one of the most critical drawbacks of 3D-printed fiber-reinforced thermoplastics: their low out-of-plane mechanical properties. Due to this factor, it is still unknown how most design and manufacturing parameters affect the out-of-plane properties of composite materials. As a solution, this paper proposes an experimental methodology to characterize out-of-plane printed composite materials. For this purpose, existing standards for traditionally fabricated composites are adapted, investigated, and validated for 3D-printed laminates reinforced with long fibers using the fused filament fabrication technique. Consequently, the methodology is employed to study the impact of stacking sequence and heat treatment conditions on the composites' out-of-plane mechanical properties. The main results showed that increasing the thickness between stacking layers increases the mechanical response due to reducing the number of fiber/matrix interfaces and, consequently, the reduction of porosity. Compared to the initial sample, a heat treatment at 175 °C for 6 h increased the interfacial strength by 101.09% and reduced the porosity in the fiber produced by the additive manufacturing process by 72%. [ABSTRACT FROM AUTHOR]

The performance of energetic composite materials is largely dependent on the energy level and combustion process. The fluorine‐containing energetic polyurethanes as binder can facilitate the combustion of metallic fuels and enhance the energy level of the energetic composites. In the current report, two kinds of thermoplastic energetic composites are prepared, based on novel fluorine‐containing energetic polyurethanes as binder and also with aluminum nanoparticles (AlNPs) and ammonium perchlorate (AP). Compared with the energetic composites with fluorine‐free energetic polyurethane binder, despite the very low fluorine content, the fluorine‐containing energetic composites not only showed higher density, lower mechanical sensitivity, much higher mechanical toughness, but also a significantly improved combustion efficiency and combustion rate of the AlNPs. [ABSTRACT FROM AUTHOR]

In the processing of thermoplastic composites, great importance is attributed to the consolidation step, as it can significantly reduce the porosity of the semi-finished product and thus influence considerably the quality of the final component. This work presents an approach to modeling the thermodynamic behavior of composite materials during hot-press consolidation. For this purpose a multi-region, multi-phase and multi-component-mixture model was developed using the simulation toolbox OpenFOAM®. The sensitivity of the model was tested by varying the thermal parameters and mesh resolution, confirming its robustness. Validity of the model was confirmed by comparing simulation results to experimental data for (i) polycarbonate with 44% carbon fiber by volume and (ii) polypropylene with 45.3% glass fiber by volume. The simulation allows very precise estimation of when a particular temperature, such as the glass transition temperature or melting point, will be reached at the core of a composite. In relation to the total process time, maximum deviation of the simulation from the experimental data amounted to 2.84%. Therefore, the model is well suited for process optimization, it offers a basis for further model implementations and the creation of a digital twin. [ABSTRACT FROM AUTHOR]

This publication summarises the current state of knowledge and technology on the possibilities and limitations of using mineral and synthetic fillers in the field of 3D printing of thermoplastics. FDM technology can be perceived as a miniaturised variation of conventional extrusion processing (a microextrusion process). However, scaling the process down has an undoubtful drawback of significantly reducing the extrudate diameter (often by a factor of ≈20–30). Therefore, the results produced under conventional extrusion processing cannot be simply translated to processes run with the application of FDM technology. With that in mind, discussing the latest findings in composite materials preparation and application in FDM 3D printing was necessary. [ABSTRACT FROM AUTHOR]

Electric motors are ubiquitous on spacecraft and their smooth operation relies on the presence of naturally magnetic materials. The employment of conventional metal‐based magnets causes some inconveniences such as high values of specific gravity and the limited reproducibility of complicated geometries. The introduction of novel polymer‐based magnetic materials processed via additive manufacturing represents a brilliant answer to these needs. This paper describes the first‐time development of a polyether ether ketone‐magnetite (Fe3O4) soft magnetic composite. The material was prepared by adding 50 wt% magnetic microparticles to the polymeric matrix. The composite material was extruded in form of filaments and 3D printed via fused filament fabrication. The thermomechanical characterization demonstrated the stability of the material at both processing ad use temperatures, while the magnetic analysis reported a typical soft magnetic behavior with 25.7 A m2 kg−1 magnetization at saturation. The measured properties were employed as inputs for the finite element analysis of an axial flux brushless direct current electric motor, as a proof of concept. The simulation of the electromechanical behavior of the motor showed promising performance for the composite material, reaching the maximum deliverable torque of about 0.8 Nm (compliant to small power aerospace applications such as micro‐actuators and mini control moment gyroscopes) with weight savings up to 50%. [ABSTRACT FROM AUTHOR]

The increasing trend of the use of synthetic products may result in an increased level of pollution affecting both the environment and living organisms. Therefore, from the sustainability point of view, natural, renewable and biodegradable materials are urgently needed to replace environmentally harmful synthetic materials. Jute, one of the natural fibers, plays a vital role in developing composite materials that showed potential in a variety of applications such as household, automotive and medical appliances. This paper first reviews the characterization and performance of jute fibers. Subsequently, the main focus is shifted towards research advancements in enhancing physical, mechanical, thermal and tribological properties of the polymeric materials (i.e., synthetic or biobased and thermoplastic or thermoset plastic) reinforced with jute fibers in a variety of forms such as particle, short fiber or woven fabric. It is understood that the physio-mechanical properties of jute-polymer composites largely vary based on the fiber processing and treatment, fiber shape and/or size, fabrication processes, fiber volume fraction, layering sequence within the matrix, interaction of the fiber with the matrix and the matrix materials used. Furthermore, the emerging research on jute fiber, such as nanomaterials from jute, bioplastic packaging, heavy metal absorption, electronics, energy device or medical applications and development of jute fiber composites with 3D printing, is explored. Finally, the key challenges for jute and its derivative products in gaining commercial successes have been highlighted and potential future directions are discussed. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

In recent past, fused deposition modeling (FDM)-based functional prototypes have been explored in printing of composites for 4-D applications as smart thermoplastics. The 3-D printed parts with 4-D properties have wide utility in structural/nonstructural engineering applications. Some studies have reported preparation of feedstock filament as composite material comprising of polylactic acid (PLA) reinforced with polyvinyl chloride (PVC), wood dust, and magnetite (Fe3O4). But hitherto very little has been reported on mechanical characterization of 3-D printed PLA-PVC-wood dust-Fe3O4 composite. The present work is an extension of study reported on mechanical and magnetic properties-based characterization of feedstock filament prepared for FDM, to understand the effect of processing parameters on properties of functional prototypes in structural/nonstructural engineering applications. For mechanical characterization, analysis of variance (ANOVA) and historical data approach have been used in optimization of 3-D printing condition in two stages. From ANOVA, it has been figured out that infill density of 100%, infill angle of 45°, and infill speed of 70 mm/s have given best result for peak strength and break strength in first stage. Further, the results of ANOVA model suggested that either there were some missing independent variables or interaction of present variables with each other was playing role in output. In second stage, historical data approach was used to understand the affect of interactions present among the input variables. The morphological analysis suggested that the sample printed with maximum density and low infill angle has minimum porosity and thus shows better mechanical properties. The results were supported with photomicrographs to understand the effect of porosity in the fractured sample. [ABSTRACT FROM AUTHOR]

Fiber reinforced resin matrix composite materials are used in airplanes, wind generators, automobiles, and other applications where stiff, light-weight materials, or parts consolidation are beneficial. Most often, the fibers are [...]

The article presents a study which reported a design of tough reversible/recyclable adhesive materials enabled by incorporating dynamic covalent bonds of boronic ester into commodity triblock thermoplastic elastomers that reversibly bind with various fillers and substrates. Topics discussed include synthesis of multiphase material incorporating interfacial dynamic bonding, mechanical properties of dynamic crosslinked multiphase composites, and tough adhesive behavior of the materials.

Thermoplastic polyamide elastomer (TPAE) is a kind of high‐performance elastomers prepared from nylon hard segments and polyether or polyester soft segments. The hard segments endow TPAE with excellent mechanical properties, while the soft segments provide the desired elasticity. Therefore, the development of TPAE as a high‐performance foam material has broad application prospects. In this work, ethylene‐vinyl acetate copolymer/polyamide‐1012 elastomer (EVA/TPAE1012) composite materials with different compositions were prepared, using ethylene‐vinyl acetate /maleic anhydride graft copolymer (EVA‐g‐MAH) as compatibilizer. Then, EVA/TPAE foamed materials were fabricated by chemical foaming method and batch foaming process, with azodicarbonamide as blowing agent. The resulting composite foams were tested in terms of density, cell properties hardness, resilience, compression recovery, and mechanical strength. The EVA/TPAE1012 foam has a low density (0.14 g cm−3), small cell size (approximately 62.1 μm), and a high cell density (3.08 × 107 cells cm−3). Compared with pure EVA foam, the composite foam not only has an increase in specific strength, resilience and tearing strength, but also has good toughness, which greatly improves the resulting foams' expansion ratio and elongation at break. [ABSTRACT FROM AUTHOR]

In order to meet environmental regulations and achieve resource efficiency in the series production of vehicles, recyclable polymer composites with a high strength-to-weight ratio are increasingly being used as materials for structural components. Particularly with thermoplastic fibre-reinforced polymers or organo-sheets, the advantage lies in the tailored mechanical properties of the final component by adapting the orientation of fibres based on the direction of loads. These components produced by thermoforming organo-sheets also offer a cost benefit and short cycle times. During the thermoforming process, the shear behaviour of the organo-sheet is the most dominant and determines the mechanical properties and quality of the resulting component. However, the current standard for characterising the shear behaviour of organo-sheets does not consider the strain and cooling rates inherent in the thermoforming process. This research investigates the influence of thermoforming process parameters on the shear behaviour of organo-sheets with a new methodology combining DSC and DMA experiments. During the thermoforming process, the transition of the matrix material from a molten state to a solid state is dictated by the crystallisation kinetics and their dependence on heating and cooling rates. Thus, non-isothermal DSC scans, which correspond to a temperature cycle in a thermoforming process, are used in the DSC experiments to establish the relationship between the recrystallisation temperature of the organo-sheet material and the cooling/heating rates in the thermoforming process. In order to achieve thermoforming-processrelevant cooling rates, fast scanning calorimetry (Flash DSC) is used in addition to conventional DSC measurements. DMAexperiments carried out with 45° fibre orientation show that the recrystallisation temperature consequently influences the shear storage modulus of the organo-sheet. The results from DSC measurements show a shift of recrystallisation temperatures to lower temperatures as the cooling rate increases. The combined analysis of results from the DSC and DMA experiments supports the findings and shows the influence of the process temperature, cooling rate and strain rate on the recrystallisation temperature and, in turn, the shear behaviour of organo-sheets. Thus, a recommendation for establishing a new standard for characterising the shear behaviour of organosheets is made. [ABSTRACT FROM AUTHOR]

Currently the development of additive manufacturing and the emerging of new materials allows to manufacturing process obtaining functional models with properties and geometries adapted to each particular case with low production times and costs. Specifically, 3D printing by fused deposition modeling (FDM) that operates with polymers, is one of the most widespread and popular techniques. Among the numerous materials available, the elastomeric polymers, whose base composition is polyurethane, are becoming increasingly important since allow to obtain flexible pieces with good mechanical and chemical resistance. The objective of this work is to study the effect of an abrasive fluid (commercial automotive petrol) on test specimens made of two different elastomeric filaments commonly used in 3D printing, thermoplastic polyurethane and thermoplastic elastomers. To do this, some of the main physical and mechanical properties – hardness, weigh variation and tensile and bending tests ‐ of these materials were analyzed after immersion of the samples in petrol for different periods of time. Specimens with different volume of material inside their structure were designed in order to determine the effect of the volume filling on the mechanical properties and the petrol effect. [ABSTRACT FROM AUTHOR]

A novel numerical approach to analyze the mechanical behavior within composite materials including the inelastic regime up to final failure is presented. Therefore, a second-gradient theory is combined with phase-field methods to fracture. In particular, we assume that the polymeric matrix material undergoes ductile fracture, whereas continuously embedded fibers undergo brittle fracture as it is typical e.g. for roving glass reinforced thermoplastics. A hybrid phase-field approach is developed and applied along with a modified Gurson–Tvergaard–Needelman GTN-type plasticity model accounting for a temperature-dependent growth of voids on microscale. The mechanical response of the arising microstructure of the woven fabric gives rise to additional higher-order terms, representing homogenized bending contributions of the fibers. Eventually, a series of tests is conducted for this physically comprehensive multifield formulation to investigate different kinds and sequences of failure within long fiber reinforced polymers. [ABSTRACT FROM AUTHOR]

Component contacting degree in a composite material is an important reference for evaluation the performance characteristics. In this article, two composite material systems involving polylactic acid (PLA) with acrylonitrile butadiene styrene (ABS) and PLA with thermoplastic polyurethane (TPU) were prepared by blending and laminating through fused deposition modeling (FDM) 3D printing technology. The mechanical and thermal properties of the as‐prepared composite materials were examined. The results indicated that PLA and TPU played a dominant role in tensile strength and breaking elongation, respectively, in individual composite material. ABS and TPU changed the glass transition peek, crystallinity, and modulus of PLA. The results also suggested that although the processing design of the blending method was more suitable for the contact between two components, but the mechanical properties of laminated composites were closer to theoretical predictions. The structural design and processing technology provide a comparative method and reference basis for studying the performance characteristics of composite materials. [ABSTRACT FROM AUTHOR]

This study aims to find the best wear resistant polymer or polymer composite pair that can be used in electrical contact breaker applications. For this, the pin-on-disc (PoD) wear test machine was used. Poly-etherether- ketone (PEEK) polymer and 20% and 30% by weight glass fiber (GF) reinforced PEEK composites were used as pin material. Long glass fiber reinforced and calcium carbonate mineral-filled unsaturated polyester composite material was used as the counterpart material. In the tribological experiments, while the effect of glass fiber reinforcement on wear was examined, the effect of the applied pressure was also investigated. The highest wear rate was obtained in PEEK+30% GF polymer composite with 4.42x10-14 m2 N-1 under 5.30 MPa pressure, while the lowest wear rate was obtained with 1.13x10-14 m2 N-1 under 1.77 MPa pressure. As a result of the study, it was determined that among the materials subjected to the wear test, the long glass fiber reinforced and calcium carbonate filled pure polyester composite material and the pure PEEK polymer pair were the most suitable pairs for electrical contact breaker applications. [ABSTRACT FROM AUTHOR]

Asource of waste post-industrial continuous glass fiber reinforced polypropylene (PP/GF) tape was investigated by means of thermo-mechanical recycling into long fiber thermoplastic (LFT) composite material. The glass fiber content was initially 70 wt.% in the tape and diluted to 40 wt.% in the LFT. Different approaches were investigated to reduce the size of the material into processable dimensions while retaining the quality of the fibers. The resulting flakes were melt-processed and the mechanical behavior determined. Competitive mechanical performance was obtained in terms of stiffness, strength and toughness compared to commercial reference materials made of long fibers. [ABSTRACT FROM AUTHOR]

This research focuses on computational microstructure to create hydrogel-cellulose ultra-sonication method for the production of additive structures and the stability of the physical characteristics of its cellulose hydrographic composite material in 4D printing. CMC with combined cellulose fibres of high cellulose content for dispersion compounds and fine dehydrated particles allows a 50% fibre matrix hydrolysis. Evaluation of the microstructure composite particle of CMC in 4D surface luminance structure and the profile structure was done. Cross-sectional views and surface roughness, waviness profile of the specimens are extracted and analysed, with the coresonding Gaussian filter for accurate decomposition of particles was carry out. The nanoparticle characterisation of the thermoplastic form was used in the mixed sedimentation process to create an polymer composite structure when analyse. The shrinkage properties of the materials are evaluated to understand the relationship between the deformation according to the time and direction of the 4D printing analysis. The ability of computational ultra-sonication microstructure to be used correctly for 4D printing is demonstrated by evaluating a complex microstructure that can change with time according to the predefined design rules to respond to moisture. The most critical feature is the cellulose gratified in the ultimate material model, which is the amount of cellulose of the ultra-sonication composite specified in the 4D printing materials of 2.5% by mass of hydrogen and 2.5% by mass of CMC. [ABSTRACT FROM AUTHOR]

Fused deposition modelling (FDM) is a widely used additive layer manufacturing process that deposits thermoplastic material layer-by-layer to produce complex geometries within a short time. Increasingly, fibres are being used to reinforce thermoplastic filaments to improve mechanical performance. This paper reviews the available literature on fibre reinforced FDM to investigate how the mechanical, physical, and thermal properties of 3D-printed fibre reinforced thermoplastic composite materials are affected by printing parameters (e.g., printing speed, temperature, building principle, etc.) and constitutive materials properties, i.e., polymeric matrices, reinforcements, and additional materials. In particular, the reinforcement fibres are categorized in this review considering the different available types (e.g., carbon, glass, aramid, and natural), and obtainable architectures divided accordingly to the fibre length (nano, short, and continuous). The review attempts to distil the optimum processing parameters that could be deduced from across different studies by presenting graphically the relationship between process parameters and properties. This publication benefits the material developer who is investigating the process parameters to optimize the printing parameters of novel materials or looking for a good constituent combination to produce composite FDM filaments, thus helping to reduce material wastage and experimental time. [ABSTRACT FROM AUTHOR]

This article presents joining methods (welding and sealing) of single-polymer composite materials in a hot air stream. The research material was created using the film-stacking method, which involves pressing successive fractions of polyethylene terephthalate-modified with glycol (PET-G) at defined technological conditions, such as pressure, temperature, and time. Joining method analysis was carried out based on the tensile test results. Analysis of the obtained results showed that the properties of the overlapped weld joint were the best because they were closest to the original materials. In contrast, PET-G welded joint properties were the worst because the PET-G welded joint does not contain fibers, which enhanced the weld; therefore, the fastest breakage of the material was observed at the welding location. For the overlapped weld, the weld itself is more resistant because the joint surface is influenced by friction forces between joined materials. [ABSTRACT FROM AUTHOR]

A classification of dispersed structures is presented for the polysulfone (PSF) + short glass fibers (GF) dispersed system, and their relationship with generalized parameter Θ and the content of dispersed filler is shown. A relationship is established between generalized structure parameter Θ and rheological properties of glass-filled PCMs based on PSF. It has been shown that the change in the parameters of the structure from a diluted to a medium-filled system leads to the formation of a quasi-continuous framework of dispersed particles at Θ = 0.45 parts by volume in dispersed-filled polymer composite materials (DFPCMs), while the viscosity of PSF-190 + GF melts increases by around three or four times in the processing temperature range from 290 to 340°C. It has been established that the introduction of glass fiber into PSF has practically no effect on the thermal stability time of polysulfone melts. Optimal temperature conditions for their processing into products by injection molding are proposed for DFPCMs based on PSF-190 + GF with different types of structures, viscosities, and thermal stability times. [ABSTRACT FROM AUTHOR]

Ultrasonic welding is a highly promising technique for joining thermoplastic to thermoset composites. A neat thermoplastic coupling layer is co-cured on the surface to be welded to make the thermoset composite 'weldable'. A reliable bond is attained when miscible thermoplastic and thermoset materials are chosen. For welding carbon fibre/polyetheretherketone (PEEK) to thermoset composite samples, a PEEK film is not preferable due to its immiscibility with epoxy resins. On the other hand, polyetherimide is an excellent candidate, since it is known to be miscible to most epoxy systems at high temperatures and PEEK polymers. This study focusses on two main subjects; firstly, the nature of the material of the energy director, i.e. a flat thermoplastic film used to promote heat generation at the interface. In this case, the energy director can be either polyetherimide, as in the coupling layer or PEEK material, as in the matrix of the thermoplastic composite adherend. It was found that both materials can produce welds with similar mechanical performance. This study focusses secondly on the thickness of the coupling layer. Due to the high melting temperature of the PEEK matrix, a 60-µm-thick coupling layer was seemingly too thin to act as a thermal barrier for the epoxy resin for heating times long enough to produce fully welded joints. Such an issue was found to be overcome by increasing the thickness of the coupling layer to 250 µm, which resulted in high-strength welds. [ABSTRACT FROM AUTHOR]

Particles are becoming increasingly popular reinforcing elements in products made by injection molding. Particles reinforcement allows the thermoplastic to be processed employing the same methods as those used for unreinforced thermoplastic. Ultrafine particles, whose diameters are comparable to the crystalline regions in the polymer, have a prominent reinforcing effect on the elastic properties of the polymer. Small particles adhere strongly to the polymer, which leads to a strong reinforcing effect. In particle reinforced thermoplastic matrix composites, loads are not directly applied to the particles but are applied to the matrix, and some of the applied loads are transferred to the particles. The process of transfer of load between particles and matrix depends on the strength of the interface. In this work, multiparticle composite model was analyzed under tensile load. The purpose of this work is to analyze the influence of particle diameter (the diameters of 19.61, 26.15, 39.22 and 78.45 m were used) on the Von Mises stress of glass particle reinforced thermoplastic nylon 66 matrix composite using finite element analysis (FEA). The second objective is to analyze the effect of particle packing (square, hexagonal and random arrangement) on nanocomposite behavior. [ABSTRACT FROM AUTHOR]

Biodegradable films based on thermoplastic corn starch (TPS) and copper particles with antimicrobial capacity were developed. Copper nanoparticles (Cu) and silica coated copper microparticles (Si-Cu) in the range of 0.25 to 5% were used. Composite films were obtained by melt-mixing and subsequent thermo-compression. Particles distribution within TPS matrix and the presence of some pores and cracks, induced by Si-Cu particles, was evaluated by SEM. The presence of both fillers gave composite films a brown pigmentation and decreased their transparency; these effects were more pronounced at higher particles concentrations. Regarding mechanical properties, copper particles at 1 and 5% acted as reinforcing agents increasing the maximum tensile strength but their presence lead to a decrease in elongation at break, affecting films ductility. Composites inhibited the growth of Gram+ and Gram- bacteria, demonstrating their antimicrobial capacity. Copper effectively migrated to a simulant of aqueous foods and naked particles concentration in the simulant medium resulted higher than the minimum inhibitory concentration for bacteria. The characteristics and properties of developed composite films make them an interesting material for food primary packaging, mainly for meat fresh products. [ABSTRACT FROM AUTHOR]

Purpose: The main purpose of this article is to update the processes of using thermoplastic materials in modern aircraft structures of aircraft. Results: The result of the analysis of the modern market for aviation technologies and aviation materials is the active use of thermoplastic materials in the structures of aircraft of leading manufacturers in the field of aircraft construction. Discussion: The introduction of technologies for using composite thermoplastic materials in aerospace structures by foreign aviation enterprises is characterized. [ABSTRACT FROM AUTHOR]

The influence of a shungite filler on thermophysical and electrophysical properties of thermoplastics has been investigated. It has been shown that filling the thermoplastics with a shungite filler is particularly efficient at a high concentration of the filler. It is the thermal conductivity and the thermal diffusivity, and also the electrical conductivity that are most substantially increased by shungite with 60 wt.% of fi ling. Here, the influence of shungite is more pronounced in the case of filling with polyamide rather than with polyethylene, which is due to the noticeable nucleating effect of shungite. It has been shown that at an equally high degree of filling, a PA6-based composite exhibits the properties of a conductor, whereas an LDPE-based one remains a dielectric. It has been established that shungite nanoparticles actively interact with the thermoplastic matrix, structuring the polymer and leading to an improvement of the thermophysical and electrophysical properties of a polymeric composite. [ABSTRACT FROM AUTHOR]