Characterization Of Composite Materials Research Articles

Investigation of acoustic characterization of ultrasonic air coupling testing of NEPE propellant under strain control

To explore the acoustic characterization of composite solid propellant materials, the wave equation of the viscoelastic body was derived based on the linear viscoelastic constitutive model, and the theoretical relationship between ultrasonic sound velocity and attenuation coefficient, which are closely related to mechanical properties, such as elastic modulus, viscosity coefficient, and complex modulus, was obtained. Ultrasonic air-coupled testing experiments of the NEPE (Nitrate Ester Plasticized Polyether) propellant under different tensile strain states were carried out to obtain the variation law of ultrasonic transmission wave peak amplitude, sound velocity, and attenuation coefficient with strain variables in combination with the variation in propellant porosity under tensile strain. Furthermore, the acoustic parameters with strain and porosity were fitted by the regression equation, and the effect of mesoscopic damage on macroscopic mechanical properties was analyzed. The results show that with the increase in NEPE propellant tensile strain, the porosity increases exponentially. With the increase in porosity, the sound velocity decreases by first polynomials, the wave amplitude decreases by second polynomials, and the attenuation coefficient increases by third polynomials.

Dynamic intralaminar fracture toughness characterisation of unidirectional carbon fibre-reinforced polymer composites using a high-speed servo-hydraulic test set-up

This paper presents an experimental investigation on the intralaminar fibre-dominated fracture of unidirectional (UD) IM7/8552 carbon-epoxy composites, loaded under quasi-static (QS) and intermediate strain rates (IR). Dynamic tensile testing is carried out using a previously proposed test methodology involving a high-speed servo-hydraulic test machine, equipped with a slack adapter, and Digital Image Correlation (DIC), with the aim of providing an alternative means to Split-Hopkinson pressure bar testing for the characterisation of similar composite materials at intermediate-to-high strain rates. Three sizes of Double-Edge Notched Tension (DENT) specimens are tested at QS and IR to obtain the mode I intralaminar fracture toughness. The results of the fracture toughness tests compare well with literature data, supporting the proposed methodology. This study is a first step towards standardising a more easily accessible test method for characterising the mechanical properties of fibre-reinforced polymer (FRP) composites over a broad range of dynamic strain rates.

Mechanical characterization of composite materials with rectangular microstructure and voids

The purpose of this work is to study the mechanical behavior of microstructured materials, in particular porous media. We consider a detailed description of the material through a discrete model, considered as the benchmark of the problem. Two continuous models, one micropolar and one classic, obtained through a homogenization procedure of the material, are studied both in static and dynamic conditions. Furthermore, the internal characteristics of the material, such as the internal scale of the microstructure and the percentage of the voids, are made to vary in order to investigate the mechanical response and to have an exhaustive comparison among the models.

Preparation and characterization of a solar-driven sodium acetate trihydrate composite phase change material with Ti4O7 particles

Thermal energy storage using phase change materials has received much attention as it can effectively relieve the contradiction of renewable energy between supply and demand. The novel bifunctional sodium acetate trihydrate (SAT) composite phase change materials with photo-thermal conversion and heat storage properties were developed to promote the thermal utilization of solar energy. The Ti 4 O 7 particles were selected as photo-thermal conversion media with full spectral absorption of sunlight and efficient photo-thermal conversion performance. 5 wt% disodium hydrogen phosphate dodecahydrate (DSP) and 3 wt% carboxymethyl cellulose were used to decrease supercooling and restrain phase separation of SAT, respectively. The as-prepared SAT composites with different content of Ti 4 O 7 possess a low supercooling degree of 0.9–1.5 °C and high latent heat of 228.6–257.7 kJ kg -1 . Ti 4 O 7 has a stable absorption capacity covering the full solar spectrum (200–2500 nm) and the absorption capacity of SAT and DSP in the infrared light even more than Ti 4 O 7 at 1900 nm–2500 nm. The SAT composite sample with 10 wt% Ti 4 O 7 has the best total solar absorption capacity of 93.33% more than Ti 4 O 7 of 92.76% because SAT and DSP have outstanding absorption capacity in the long-wave infrared wavelength. The photo-thermal storage efficiency of all SAT composite photo-thermal conversion phase change materials exceeds 50%, of which the composite with 10 wt% Ti 4 O 7 has the optimal photo-thermal conversion storage efficiency of 76.63%. The composite photo-thermal storage phase change materials have potential applications in solar energy systems. • The SAT-based composites have optical absorption and thermal storage properties. • The absorption capacity of the composite phase change materials is 93.33%. • The optical photo-thermal conversion and storage efficiency is 76.63%. • Ti 4 O 7 was a vital component in facilitating solar to heat for phase change materials.

Finite Difference Model for the Bond Behaviour of Polyparaphenylene Benzobisoxazole (PBO) Fibre-Reinforced Composite System for Retrofitting Masonry

This study addresses a numerical investigation of the bond behaviour exhibited by an FRCM system when subject to tensile and single direct shear tests. A reinforcement system, based on a polyparaphenylene benzobisoxazole (PBO) bi-directional fibre mesh and a mixed cement-pozzolanic mortar is selected. The system is characterized by the presence of coated glass-fibre yarns and dry polypropylene yarns alternated to the PBO yarns in the warp and weft directions, respectively. The mechanical characterization of composite constituent materials is carried out together with tensile and direct shear tests. Concerning mechanical interpretation of the tests, within a mode II fracture mechanics, and assuming a trilinear cohesive material law (CML), the stress transfer law between the fibre and the matrix is back calibrated from single direct shear test results. The CML obtained is employed into a finite-difference model developed for the purpose. Tensile tests are modelled providing adequate boundary conditions. Results satisfactorily agree with the tested behaviour of the FRCM system.

Physico-Chemical and Thermomechanical Analysis and ‎Characterization of ‎a Thermoplastic Composite Material Reinforced by Washingtonia Filifera Novel Vegetable Fibers

In this paper, ‎morphological, physico-chemical and thermal properties investigations‎ are carried out for a ‎novel ‎composite material reinforced by Washingtonia Filifera (WF) palm fibers using a 20 weight (wt) % loading rate. The experimental analysis by Scanning Electron Microscopy (SEM) shows the longitudinal roughness of the surface, which plays a very important role in the adhesion between the WF fibers and the High Density ‎PolyethylenE (HDPE) resin. FTIR tests of the composite (WF 20%/ HDPE) represent out of plane vibrations involving ring and CH2 symmetric bending in cellulose chain.‎ Thermogravimetric analysis (TGA) and Derivative thermogravimetric ‎(DTG) thermal analysis show a thermal stability at 210°C, 2.5% residual mass ‎and 745 °C maximum ‎temperature. X-Ray Diffraction (XRD) analysis shows that the ‎crystallinity index is 59.2%, with a size of ‎‎23 nm. Using tensile tests, a Young modulus of 858.6 MPa, ‎17% elongation and a maximum stress of 15 MPa ‎are found. The obtained characteristics of WF reinforced composite are better than those of Bamboo reinforced composites which has been proven to have characteristics superior to those of standard particleboard and medium density fiberboard used mainly in the construction industry.

Experimental and material characterization of composites, including waste iron and marble powder.

Due to its fine particle size, waste marble slurry originating in cutting and processing units mixes into the air after drying, causing environmental and health problems in nearby areas. On the other hand, large amounts of iron particles are generated as metalworking industry waste, affecting the environmental system. In this study, 0%, 10%, and 20% marble powder (instead of cement) and iron particles (instead of fine aggregate) were used in mixtures, and the composites produced were subjected to two different curing periods: 7 and 28days. The physical, mechanical, microstructural, and thermal properties of the fresh and hardened composites were ascertained via bulk density, consistency, porosity, water absorption, capillary water absorption, strength tests, particle size distribution, X-ray diffraction (XRF), X-ray fluorescence (XRF), scanning electron microscopy and energy dispersive spectroscopy (SEM-EDS), and thermogravimetric analyses (TGA). The results revealed that minimum water absorption (8.5%) and porosity (19.8%) values were achieved in 28-day composites produced with 10% marble-20% iron wastes among all composites. Thus, iron particles substituted for natural aggregates were mainly responsible for the increase in mechanical performance. A maximum flexural strength of 5.9MPa and a compressive strength of 26.7MPa were observed in 28-day composites containing 0% marble-20% iron wastes. Furthermore, capillary water absorption tended to decrease with the substitution of 10% marble powder.

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.

A Numerical Study for Determining the Effect of Raffia, Alfa and Sisal Fibers on the Fiber-matrix Interface Damage of Biocomposite Materials

Background: Nowadays, natural fibers are used in all industrial fields, particularly in automotive technology and civil engineering. This great emergence is due to their biodegradability, recyclability and have no environmental effect. Objective: In this article, the effect of raffia, alfa and sisal fibers on the damage of biocomposite materials (raffia/PLA (polylactic acid), alfa/PLA and sisal/PLA), subjected to the same mechanical shear stress, has been investigated. Method: To calculate the damage to the interface, the genetic operator crossing is employed based on the fiber and matrix damage. Result: The results have shown that the raffia / PLA and alfa/PLA biocomposite materials are better mechanical properties compared to sisal / PLA, this observation has been confirmed by different values of interface damage of the biocomposite studied. Conclusion: The numerical results are similar and coincide perfectly with the results of Cox where he demonstrated that the Young's modulus of fibers improves the resistance of the interface. These conclusions are in very good agreement with our numerical data presented by the red cloud, and in good agreement with the work presented by Antoine Le Duigou et al. and Bodros et al. in which they have shown that natural fibers greatly improve the physical characteristics of composite materials.

Synthesis and characterization of a collagen-based composite material containing selenium nanoparticles.

Multidrug-resistant bacterial strains represent an emerging global health threat and a great obstacle for bone tissue engineering. One of the major components of the extracellular matrix of the bone is a collagen protein, while selenium is an element that has antimicrobial potential, and is also important for bone metabolism and bone health. Here we represent the incorporation of selenium nanoparticles (SeNPs) synthesized by the green chemical reduction method into collagen gels to produce a composite material, collagen/SeNPs, with antimicrobial properties. The samples were comprehensively characterized by zeta potential measurements, dynamic light scattering inductively coupled plasma-mass spectrometry (ICP-MS), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), optical microscopy, field-emission scanning electron microscopy (FE-SEM), and differential scanning calorimetry The cytotoxicity of the SeNPS, as well as collagen/SeNPs, was tested on the MRC-5 cells. It was revealed that collagen/SeNPS expressed a lower cytotoxic effect. Collagen/SeNPs showed significant antibacterial activity against all tested Gram-positive strains, the major causative agents of orthopedic infections as well as Candida albicans. Furthermore, three-dimensional β-tricalcium phosphate (3D-TCP) scaffolds were fabricated by a well-established 3D printing (lithography) method, and afterward preliminary coated by newly-synthesized SeNPs or collagen/SeNPs. In addition, uncoated 3D-TCP scaffolds as well as coated by collagen/SeNPs were subjected to biofilm formation. The production of Staphylococcus aureus biofilm on coated scaffolds by collagen/SeNPs was significantly reduced compared to the uncoated ones.

Advanced fuzzy arithmetic for material characterization of composites using guided ultrasonic waves

In this study, a technique based on guided ultrasonic waves coupled with an uncertainty analysis based on fuzzy arithmetic is developed to quantify the nominal values of a inherent epistemic uncertainty in the material constants of quasi-isotropic fiber-reinforced composites. It is shown that the measured group velocities may vary depending on the location across the aerospace-grade laminate, raising the question of whether the assumed nominal values of the material properties could accurately represent the entire material system in any region. Thus, fuzzyfied material properties are identified through the use of an inverse fuzzy arithmetical approach, which has been shown to be efficient and effective for dynamic systems with epistemic uncertainty. After the identified material parameters are defuzzyfied, a new set of nominal values for the material properties is determined. These preliminary estimates may allow for the development of more efficient nondestructive material characterization techniques in the future.

Comparative study of thermo-mechanical and thermogravimetric characterization of hybrid dental restorative composite materials

The purpose of the study is to create resin-based micro-nano particulates-filled dental restorative composite materials and investigate the influence of variable nano-hydroxyapatite filler concentration on their thermo-mechanical and thermogravimetric properties. Two series were created by combining silane treated nano-hydroxyapatite filler particles (wt.% of 0, 2, 4, 6, and 8) with foreign ceramic particles (alumina and titanium oxide). Each series consists of five compositions. For each dental composition, the amount of foreign ceramics (20 wt.%) remained constant. The dental composite samples were polymerized for 30 s on each side using a blue LED light. Thermo-mechanical and thermogravimetric analysis was performed at various temperatures range. At preliminary temperatures (30–40°C), the hybrid nano-hydroxyapatite-TiO2 dental composite filled with 8 wt.% nano-hydroxyapatite exhibited storage modulus (about 90 MPa) whereas nano-hydroxyapatite-Al2O3 dental composite filled with 8 wt.% nano-hydroxyapatite exhibited storage modulus (about 260 MPa). Themal stability of nano-hydroxyapatite-Al2O3 and nano-hydroxyapatite-TiO2 dental composite was 99.90% and 99.82% at 90°C, respectively. The glass phase, glass transition phase, and rubbery phase were observed at various temperatures. From the results, it revealed that Al2O3-nano-hydroxyapatite filled dental composite was observed significant than TiO2–nano-hydroxyapatite filled dental composite.

Design of adhesive-bonded structure solutions, contribution of the modelling of the adhesive

Finite element modelling of adhesive joints has been analysed in this work, applying the results and conclusions of the design process of a multi-material base of an elevator. The main approach of the study has been the modelling of the adhesive joint, different parameters and its application in complex models. For that purpose, a case study has been carried out in a simply supported plate model. Several modelling techniques have been analysed and design recommendations have been proposed. Characterization of composite materials and adhesives has also been studied, given the fact that the anisotropy of the composites is an additional difficulty in the Finite Element Analysis. Having the real properties of these materials is a very important factor for efectiveness in terms of economical and computational cost. The correlation of simulation and experimental results has been analysed in the practical case study and the contribution of the adhesive modelling has been studied. To conclude, the importance of the material characterization and the sensitiveness to the variation of their properties are to be mentioned. The work offers the designer several recommendations on adhesive joint modelling as well as parameters that might affect the analysis of a structure that contains adhesive bonding.

Printability Characterisation of Different Composite Materials for Additive Manufacturing of 3d Bone Scaffolds

Printability Characterisation of Different Composite Materials for Additive Manufacturing of 3d Bone Scaffolds

Design and Characterization of Hierarchical Aluminosilicate Composite Materials for Cs Entrapment: Ionic Exchange Efficiency Tied to Microstructure

Design and Characterization of Hierarchical Aluminosilicate Composite Materials for Cs Entrapment: Ionic Exchange Efficiency Tied to Microstructure

Synthesis, characterization and application of polymer composite materials in wastewater treatment

The concern towards the increasing challenges in water treatment technologies made investigators towards significant innovations in current years. The incorporation of polymer composite materials in this field obtained remarkable results due to its exceptional properties. Among them, Activated carbon (AC) and surface modified activated carbon by thermo gravimetric analysis (TGA) have proved to be promising materials due to their large surface area, enhanced process ability, stability, synergetic properties, cost-effectiveness, and less impact on the environment. The study focused on various treatment parameters from wastewater by performing a series of batch experimental studies by changing parameters pH, stirring time, adsorbent dosage, temperature and agitation speed in decreases using % of AC/LDPE with most efficient way. It was observed that the optimum parameter pH: 5, rpm: 100, amount of dosage: 1.6g, stirring time: 60 min and T: 35 °C. The results suggest that AC/LDPE were found to be more efficient in application of wastewater treatment.

Fabrication and preliminary assessment of aramid reinforced polymer composite material

A knowledge of the material constituents and fabrication process is generally required for easing the composite material properties study and characterization. This paper presents the methodology of aramid reinforced polymer composite material preliminary assessment and fabrication. The demonstration is carried out through the development of mechanical properties characterization specimen. The composite material specimen is fabricated by utilizing the open mould with hand lay-up method, where three types of laminates include of unidirectional, orthotropic, quasi-isotropic cross plies are demonstrated. A template is applied for preparing specific fibre orientation 45°angle. Plies are lay accordingly with guided by a square guide for minimizing the off-orientation angle defect. Preliminary assessment is included of verification of unidirectional aramid fabric quality, cured specimen physical defect, internal defect through micrography analysis and material volume fraction prediction. Average specimen fibre volume fraction of 0.64 is predicted by determined the fibre filament geometry detail through micrography analysis. There are several fabrication defects had been identified. The defect identification findings shall be referred for further improvement of material preparation and fabrication method.

Fabrication and characterization of micro alumina zirconia particulate filled dental restorative composite materials

AbstractComposite resin is quickly becoming the most extensively utilized material in the field of cosmetic and restorative dentistry. It eliminates the problem of poisonous nature caused by the amalgam's mercury content. This research article is based on the outcome of adding micro‐alumina and zirconia particulates filled dental composites on the physical properties, mechanical properties, and wear analysis. Three dental composites named AZDC2, AZDC4, and AZDC6, were prepared. Alumina microparticles were constant (6 wt%) while zirconia microparticles were varying (2, 4, and 6 wt%). Two‐body wear was performed on pin‐on‐disc friction & wear test rig under dry sliding for all three dental composites under different normal load (20, 40, and 60 N) and sliding speed (10, 15, and 20 mm/s). The experiments were designed as per L9 Taguchi orthogonal array. The least volumetric wear was found in AZDC6 dental composite under a sliding velocity of 15 mm/s and a normal load of 20 N. From the ANOVA analysis, normal load and filler content were the significant factors affecting the volumetric wear with a significance level 5%, respectively. Dental composite AZDC6 exhibited maximum compressive strength (451.49 MPa). Micro hybrid particulates‐filled dental composites improve physical and mechanical characterization.

Research on preparation and characterization of Ti-Ti5Si3 gradient composite porous material via in-situ reactive process

Gradient composite porous material can reach a high filtering accuracy with larger filtration flux, and the filter elements applied in separation equipment can enhance the filtration efficiency and reduce the energy consumption. Ti-Ti5Si3 gradient composite porous material was successfully prepared by in-situ reaction process with the raw materials of Ti powder and high purity quartz tablets. Microstructures and filtration properties prepared under different synthesized conditions have been studied, including the parameters of pressure sintering (additional loads and temperatures) and powder particle sizes. The synthesized granules on the membrane are well distributed with the size of ∼1.0 µm, and the thickness of the membrane is 3.0∼6.3 µm. The relative air permeability coefficient of porous membrane reduces raptly compared to the sample matrix due to the decrease of pore size. The all synthesized membranes show the presence of Ti and Ti5Si3 phases. There are two distinct layers observed in the membrane layers prepared by fine powder due to in-situ over-reaction.

Non-segmentation image-based finite element modeling (NSIB-FEM) for mechanical characterization and design of composites of fine particles

Image-based finite element modeling (IB-FEM) is a powerful tool for the characterization and design of various composite materials. However, conventional IB-FEM methods suffer from a number of deficiencies. To eliminate these deficiencies, a so-called non-segmentation image-based finite element modeling (NSIB-FEM) approach is proposed in this paper. The major difference between NSIB-FEM and conventional IB-FEM is that a finite element is allowed to contain more than one material phase, and the key step in NSIB-FEM is to determine element effective material properties. Theoretically, any micromechanics model of particulate composites can be applied for the calculation of element effective properties. A number of such micromechanics models, including Voigt’s model, Reuss’ model and Mori-Tanaka method, were tested to study how they affect the accuracy of NSIB-FEM. NSIB-FEM was validated against reported experimental data and compared with predictions by voxel-based finite element modeling. The results show that NSIB-FEM is a promising approach for the characterization of fine-particulate composites, the micromechanics model used to calculate element effective material properties has significant effect on the accuracy of NSIB-FEM. Further effort needs to be devoted to develop a more accurate method for the calculation of element-level effective material properties with the ability to deal with high volume-fraction of inclusion and element-level material anisotropy.