Design Of Composite Materials Research Articles

A Novel High Recognition Rate Defect Inspection Method for Carbon Fiber Plain-Woven Prepreg Based on Image Texture Feature Compression.

Carbon fiber plain-woven prepreg is one of the basic materials in the field of composite material design and manufacturing, in which defect identification is an important and easily neglected part of testing. Here, a novel high recognition rate inspection method for carbon fiber plain-woven prepregs is proposed for inspecting bubble and wrinkle defects based on image texture feature compression. The proposed method attempts to divide the image into non-overlapping block lattices as texture primitives and compress them into a binary feature matrix. Texture features are extracted using a gray level co-occurrence matrix. The defect types are further defined according to texture features by k-means clustering. The performance is evaluated in some existing computer vision and machine learning methods based on fiber recognition. By comparing the result, an overall recognition rate of 0.944 is achieved, which is competitive with the state-of-the-arts.

Adjustable frequency shift of laminated DNA microbeam under complex detection conditions by different packaging patterns

Packaging patterns have close correlation with thermoelastic properties of sensitive layer and relevant biodetection signals of laminated microbeam. In this paper, we present a cross-scale mechanical model to explore the possibility of adjusting thermoelastic properties of DNA adsorption film and the relevant signals of microbeam under complex detection conditions by different packaging patterns. First, considering microscale interactions in DNA solutions, a unified mesoscopic free energy is developed based on the previous formulations of Parsegian et al.; then, the thought experiment method for DNA film and the force balance method for nonlinear elastic network of DNA cylinders are combined to characterize elastic properties of adsorption film; finally, an effective macroscopic model for DNA microbeam is used to predict resonance frequency shift caused by DNA adsorption and temperature fluctuation in high-valent salt solutions. Results show that, compared with the properties of classical convex-packaged film, the thermal expansion coefficient of concave-packaged DNA film in high-valent salt solutions is smaller, and its elastic modulus and prestress have larger fluctuation ranges to environmental conditions, which provide a chance to improve detection sensitivity based on frequency shift. These results are expected to provide an option for design of DNA composite materials and microbeam sensors.

Green Conductive Construction Materials Toward Sustainable Infrastructures

Smart construction materials are intelligent composites that have properties different from normal materials. The smartness of building materials and structures is achieved through material composition design, special processing, the introduction of other functional components, or modification of the microstructure. Conductive concrete is one of the smart construction materials. It is a mixture containing a certain amount of electrically conductive components (filler). It is designed to enable the conduction of electricity. When the conductive filler used is a natural material, the result is green conductive concrete. The current work deals with a review that summarizes the vital points of the incorporation of conductive fillers in construction materials. The types of conductive filler, including green ones, the methods of production, testing, and applications of conductive cement-based composites are addressed and highlighted. Conclusions are made according to the literature reviewed, and some points of view are proposed for future perspectives.

The dual effect of shellac on survival of spray-dried Lactobacillus rhamnosus GG microcapsules

Heat shock and hygroscopicity are two main factors that resulted in low viability of probiotics in spray-dried microcapsules during storage. Hydrophobic polyester shellac was combined with whey protein isolate (WPI) to solve this problem. The results suggested that although the survival rate after drying decreased from 20.63% to 0.01% with increased shellac to WPI ratio, the 1:1 shellac-WPI provided the best protection among all samples during storage. The consistence between moisture-adsorption-isotherm and bacterial inactivation constants confirmed the moisture barrier effect of shellac under moderate humidity. Single-droplet drying and differential scanning calorimeter revealed that shellac addition reduced the drying rate and glass transition temperature of microcapsules, which in turn decreased the membrane integrity and growth capability of the probiotics after drying. This study revealed the dual effect of hydrophobic material on instant and long-term survival of spray-dried probiotic microcapsules, which provided new sight to the design of composite wall materials.

Design of Functional Carbon Composite Materials for Energy Conversion and Storage

Design of Functional Carbon Composite Materials for Energy Conversion and Storage

Frontispiece: Designable Guest‐Molecule Encapsulation in Metal–Organic Frameworks for Proton Conductivity

By encapsulating various designable molecules in metal organic frameworks (MOFs), the proton conductivity of composites can be improved. Here we classify these designable molecules into four types, and discuss the effect of their introduction on the improvement of the proton conductivity of MOFs. We hope to provide some feasible guidance for the design and development of future composite proton-conducting materials for MOFs encapsulating guest molecules. For more details, see the Review by C.-X. Zhang, Q.-L. Wang, et al. (DOI: 10.1002/chem.202103732).

Inorganic additive-incorporated composites with infrared radiation performance for thermal management

PurposePersonal thermal management in functional textiles is in increasing demand for health care, outdoor activity and energy saving. Thus, developing new strategies is highly desired for radiative cooling and/or heating by manipulation of the transmissivity, reflectivity and absorptivity of the textiles within solar energy and human body heat radiation ranges.Design/methodology/approachInorganic additives including TiO2, Fe2O3, carbon black (CB), graphene and mica were incorporated into polymer films. The inorganic additives' full spectrum properties and thermal responses were comprehensively investigated.FindingsThe CB composite film showed the highest absorptivity over the full solar to human body radiation spectrum. The mica-white (mica-w) (mica coated with TiO2) and mica-red (mica-r) (mica coated with Fe2O3) composites showed the lowest solar energy absorptivity and a strong body heat radiation reflectivity. Furthermore, according to composites' thermal responses to the simulated solar and human body radiations, CB and mica are promising for both cooling and heating when applied in dual-functional thermal management textiles.Research limitations/implicationsResearch has limitation related the amount of additives which can be added to textile. When powder is added to polyester yarn, the amount is limited by 2–3%. When powder is added to the composite which is used for printing, the amount of powder is limited by 5%.Practical implicationsA lot of apparel, especially sport apparel, contains prints. Decoration is one part of print application. Now, a lot of companies work under development of different additives, which provide additional properties to apparel. The closest targets for powder added to prints are cooling and heat retention. Quite often, inorganic additives possess dual properties: the inorganic additives may be heat reflective which his needed for heat retention, but may have high-thermal conductivity, which works well for cooling. Human body has complicated mechanism of heat exchange: convection, radiation and moisture evaporations play main role. The same additive may be cooling if there is a contact with skin but may be heating (IR reflective) if placed in the second or third layer. Thus, effect is needed to be studied first before real application.Originality/valueThis work could provide a comprehensive guideline for the rational design and application of thermal management composite textile materials by revealing the full solar to human body radiation performance of a series of inorganic materials.

Hybrid Composites for Railway and Transportation Uses – A Review

The transportation industry with airways, road transportation, shipping, and railways is a huge market for composites both military and civil applications. The need for sustainable and lightweight solutions triggered the need for composite materials. There are many different approaches for composite materials design and manufacturing to optimize the properties in strength, acoustic, and many more like such as ballistic, thermal management, and so onetc. The use of various reinforcing elements for various resins created endless options for materials scientists and designers. Among a variety of possibilities, the use of hybrid reinforcement has been quite a new approach for the composites, which is analogous to composite to optimize the performance of the final properties, such as impact, ultimate tensile strength, modulus value, thermal properties, and other properties. In this review article, the future of the transportation sectors, the advantages of railway transportation in this area, and an overview of the railway and transportation industry are presented. Definitions of hybrid composites are made and examples of applications of hybrid composites used in the railway industry are shown. Studies and research in this field were examined and, in this perspective, the contribution of hybrid composites to future studies is stated.

Morphology-size synergy strategy of SiC@C nanoparticles towards lightweight and efficient microwave absorption

Micro nanocomposites with multi-media components and rich heterogeneous interfaces have been proved to be the preferred electromagnetic functional bodies, especially in the field of electromagnetic wave absorption. The special composite structure of hollow, mesoporous and core–shell has excellent adjustable potential, it is also a high-quality route to expand electromagnetic characteristics. Herein, a synergistic strategy for sphere-line morphology evolution and particle size control of SiC/C composites by varying the calcination temperature and pH environment is proposed. The results show that the sample calcined at 1350 ℃ is hollow mesoporous [email protected] microsphere ([email protected]), it has the most excellent microwave absorption (MA) performance when the amount of ammonia is 3 ml, its effective absorption bandwidth (EAB) is 5.61 GHz at 2.1 mm, and the maximum reflection loss (RLmin) is −45.61 dB at 13.2 GHz. The excellent performance is due to the combination of good impedance matching and strong dielectric loss brought by semiconductor SiC/C composites. Multi-angle control strategy of hollow mesoporous [email protected] heterostructure and particle size can effectively adjust the electromagnetic parameters, which provides useful thinking for the design of other nano-scale dielectric composite materials.

Machine learning-aided design of composite mycotoxin detoxifier material for animal feed

The development of food and feed additives involves the design of materials with specific properties that enable the desired function while minimizing the adverse effects related with their interference with the concurrent complex biochemistry of the living organisms. Often, the development process is heavily dependent on costly and time-consuming in vitro and in vivo experiments. Herein, we present an approach to design clay-based composite materials for mycotoxin removal from animal feed. The approach can accommodate various material compositions and different toxin molecules. With application of machine learning trained on in vitro results of mycotoxin adsorption–desorption in the gastrointestinal tract, we have searched the space of possible composite material compositions to identify formulations with high removal capacity and gaining insights into their mode of action. An in vivo toxicokinetic study, based on the detection of biomarkers for mycotoxin-exposure in broilers, validated our findings by observing a significant reduction in systemic exposure to the challenging to be removed mycotoxin, i.e., deoxynivalenol (DON), when the optimal detoxifier is administrated to the animals. A mean reduction of 32% in the area under the plasma concentration–time curve of DON-sulphate was seen in the DON + detoxifier group compared to the DON group (P = 0.010).

Design, pultrusion manufacturing, characterization, and reliability testing of a novel PMMA-based glass FRP composite material

Thermosetting resins have a limited ability to absorb impacting energy and deform in the transversal direction. Thermoplastics, on the other hand, are reformable meaning their shape can be modified after the polymerization process has occurred. However, they are generally more viscous, making them non-ideal candidates in impregnation-based pultrusion manufacturing. This paper presents the experimental design, manufacturing, microstructural characteristics, and mechano-environmental testing results of pultruded Ø9.3 mm poly-methyl methacrylate (PMMA) thermoplastic GFRP rebars. The mechanical and environmental testing, performed via heat/UV/water exposure, cold environment, and corrosion followed by a series of 3-point flexural bending tests, revealed no statistical difference in the means of the flexural strengths between the thermoset- and thermoplastic-based GFRPs.

Synthesis of Mn O @C hybrid composites for optimal electromagnetic wave absorption capacity and wideband absorption

• Different manganese oxide/carbon hybrid composites have been synthesized. • The relaxation times of composites have been discussed in detail. • The optimal performance with RL min of -76.0 dB and EAB max of 5.2 GHz were achieved. The fabrication of high-performance electromagnetic (EM) wave absorption (EMA) materials is an effective strategy to deal with ever-increasing EM pollution. In this work, a series of manganese oxides/porous carbon (Mn x O y @C) hybrid composites are obtained by a two-step process. It is revealed that different manganese oxides play various influence on the dielectric properties of absorbers. Owing to the moderate complex permittivity of MnO@C hybrid composites, the optimal reflection loss could reach as high as -76.0 dB at the matching thickness of 2.0 mm with 5.2 GHz of effective absorption bandwidth at thickness of 2.1 mm. We demonstrated that the addition of porous carbon is vital for enhancing EMA performance of composites, which not only coordinates impedance matching allowing more EM waves enter the absorber, but also provides the path for electron movement, thus profiting conductive loss. Besides, different heterogeneous interfaces including porous carbon, manganese oxide and so on, are conducive to contribution of interface polarization. The most noteworthy is ingenious design of composite materials and systematic research of EM energy attenuation mechanism in this work will provide the possibility to realize high-performance EMA.

Aggregate shape effect on fracture and breakage of cementitious granular materials

To assess the aggregate shape influences on the cementitious granular material fracture and breakage behaviors, mortar samples containing two types of aggregates with same material but different shapes, namely, irregular glass particles and rounded glass particles, are compressed under quasi-static to high strain rate (1000–3500 s−1) loadings. Experimental results reveal that the extent of aggregate shape effect on the mortar stiffness is significantly enhanced with the increase of strain rate or cement strength. Although the critical strain energy is discovered to be aggregate shape independent, different microscopic fracture evolutions induced by the aggregate shape influences still exist and are effectively reflected by the corresponding coupled evolution of fragment size and shape. Meanwhile, the fracture locality preference within the aggregate particles is also validated by the associated microscopic evidence. This study sheds light on the future high strength granular composite material design, in particularly, upon high strain rates.

Solar power harvesting with metal modified windshield glass to obtain hot water

Energy solar harvesting through low environmental impact resources is an underlying objective for future technological developments. In this work, an innovative design of a vitro-metallic composite material is developed with Cu0, Zn0 and ZnO microparticles dispersed in a glass-ceramic matrix. The uppermost feature of these materials is that they are made of the reused of vehicle windshield glass disposed. The vitreous composite performance is evaluated in different seasons and under diverse weather conditions. The energy absorption is analyzed from the results of the UV–vis spectra and SEM images of the different composites. In this work it is demonstrated that the studied material has a good performance even in low temperature regions, reaching an efficiency between 30 to 50 [KJ/ KgH2O] with a 0.3% wt of metal-modified glass-ceramic material in water. The material response was analyzed through the composite material UV–vis spectrum. The new glass-ceramic materials are efficient in the process of heating water without the need of expensive devices or other forms of energy applications.

Teaching design of composite structures through Composite Analysis and Design Apps (CADA) and Design Challenges

AbstractAlthough composite materials are used in many industries nowadays, an educational tool for the design of laminated composite structures is missing in the literature. This study discusses the most important features that should exist in such a tool and, hence, presents the “Composite Analysis and Design Apps” (CADA) tool. To improve engineering students' design skills, engineering curricula should be supplemented with many design problems and course projects that focus on design, rather than analysis, of engineering components or systems. To incorporate more design problems into the curriculum of a senior undergraduate course on “mechanics and design of composite materials” in a more interesting way, an educational intervention, called the “Design Challenges,” is also presented in this study. The effect of using CADA in the Design Challenges to improve students' design skills is detailed. The study involved 21 mechanical engineering students who worked in 7 teams in each challenge. Performance of student teams in each challenge, student self‐reporting surveys, and students' performance in a design problem in the final exam were the three assessments evaluated. Assessment results proved that the Design Challenges were successful in increasing students' understanding and interest in the design of composite structures and improving their skills in tackling design problems. CADA also proved to be an effective and efficient tool for the analysis and design of thin composite laminates.

Fabrication of amorphous and high-entropy biphasic composites using high-frequency ultrasonic vibration

With the adoption of a high-frequency ultrasonic vibration method, we successfully fabricated the composites of amorphous and high-entropy alloys. The low-temperature and low-stress method enables us to fabricate composites which unite both crystalline and amorphous properties. Through adjusting the mass ratios of amorphous and high-entropy alloys in the composites, the regulation of the properties of the composites was achieved. Microscopic observations demonstrate that the composites of all proportions exhibit good bonding quality without the existence of pores or cracks. Due to the mixture of amorphous and crystalline phase, the mechanical properties of the composites were optimized compared to that of the pure single-phase materials. Our results provide ideas for the design and fabrication of composite materials containing multiphase and multi-component with specific properties.

The electrochemical energy storage and photocatalytic performances analysis of rare earth metal (Tb and Y) doped SnO2@CuS composites

The rational design of composite electrode and catalyst materials is critical for increasing high energy density and structural stability, electron-hole pair production in supercapacitors, and photocatalytic applications. By employing a simple hydrothermal technique, we were able to produce SnO2, CuS, SnO2@CuS, Tb doped SnO2@CuS, and Y doped SnO2@CuS samples. Various analytical techniques such as PXRD, FTIR, UV, SEM, EDS, and XPS examine the synthesized materials' structural, optical, purity, morphology, and binding energy. The fabricated asymmetric Y doped SnO2@CuS/AC device revealed the energy and power densities of 16.2 W h kg−1 and 740 W kg−1 at a current density of 1 A/g, with outstanding cycle stability of 80.9% retention capacitance after 5000 charge–discharge cycles. Furthermore, when exposed to visible light, the Y doped SnO2@CuS catalyst degrades the methylene blue dye with a maximum degradation efficiency of 97%. All of the above results suggested that the obtained Y doped SnO2@CuS material can be utilized in supercapacitor and photocatalytic applications.

Bias-normal index: A new indicator of dense random packing for thermal polymer/ceramic composites

Thermal composites are widely used in thermal management. Usually, they consist of polymers and fillers. In pursuit of higher thermal conductivity, the fillers are mostly spherical particles for higher packing density. In previous work, the relationship between particle size distribution (PSD) and packing density was studied, especially the parameters such as polydispersity δ and the skewness S are defined to characterize the PSD. However, in our observation, for sieving process, which is very helpful in manipulating PSD and thus tuning thermal conductivity, δ and S are not good enough to explain most of the compositing results. Here, we suggest a new set of indices (bias-normal indices) to evaluate the sieving efficacy. Three kinds of ceramic powders (MgO, Al 2 O 3 , and AlN) and their single- and triple-order composites materials were prepared. The results show that the explanations based on bias-normal ratio index agree well with all the experiments. Thus, this new indicator is competent in guiding the recipe design of the thermal composite materials, and when well-designed recipes are employed, sieving is proven an efficient and simple way to promote the thermal performance, which is of great practical value.

Hierarchical sandwich NiFe layered double hydroxide/reduced graphene oxide for high energy density asymmetric supercapacitors

• A hierarchical sandwich-type NiFe layered double hydroxide/reduced graphene Oxide (NiFe-LDHs/rGO) composite electrode materials have been designed and synthesized via a facile impregnation method. • The NiFe-LDHs/rGO composite electrode can achieve a high specific capacitance of 1319 F g -1 at 1 A g -1 and show good cycling performance over 1000 cycles. • The asymmetric supercapacitor based on NiFe-LDHs/rGO as a positive electrode and N-doped hollow carbon sphere as a negative electrode was assembled and exhibited a high energy density as well as good cycling stability. Rational design and fabrication of composite electrode materials with high energy storage performance of supercapacitors is of great importance from both theoretical and practical viewpoints. Herein, a hierarchical sandwich-type NiFe layered double hydroxide/reduced graphene Oxide (NiFe-LDHs/rGO) composite electrode materials were successfully synthesized through a one-step hydrothermal method. It is found that the prepared NiFe-LDHs/rGO composite electrode can achieve a high specific capacitance of 1319F g −1 at 1 A g −1 and show good cycling performance with a retention rate of 80% over 1000 cycles. Furthermore, the asymmetric supercapacitor based on NiFe-LDHs/rGO as a positive electrode and N -doped hollow carbon sphere as a negative electrode was assembled and exhibited a high energy density of 37 Wh kg −1 at a power density of 423 W kg −1 as well as good cycling stability. The exceptional electrochemical performance of the NiFe-LDHs/rGO composite indicates its potential application in high-performance supercapacitors.

A novel sound absorber design of nanofibrous composite porous material

This study mainly focuses on the structural design, acoustic performance prediction, and experimental validation of a novel composite sound absorber that is similar to the feather surface structure of barn owls. The composite sound absorber is composed of an ultra-light nanofibrous membrane backed with a substrate porous materials layer (NMSPM). A theoretical NMSPM model is proposed for predicting the sound absorption coefficient (SAC) of NMSPM. The experimental results demonstrate that the nanofibrous membrane can effectively improve the acoustic performance of substrate porous materials (SPM) based on specific material parameters conditions, which also compare well with the numerical results of the theoretical NMSPM model. The applicability of the theoretical NMSPM model for different sorts of SPMs is explained based on both the experimental and numerical results. A suitable thickness range of nanofibrous membrane for effectively improving the SAC of SPM is given through a series of numerical analyses. This study may provide new thinking for a novel composite sound absorber design without weight sacrifices.