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To address the challenge of balancing load-bearing and electromagnetic (EM) wave absorption properties in aircraft composite skin, the outstanding mechanical and electrical characteristics of carbon fiber (CF) prepregs were utilized to construct a carbon fiber dual-polarized absorbing laminated structure (CFDALS). The bidirectional CF arrays were introduced into the glass fiber (GF) laminated structure, to endow the laminated structure with dual-polarized EM wave absorption performances. Additionally, the excellent load-bearing capacity of the CF reflector was used to enhance the mechanical properties. Simulation results indicate that, the CFDALS achieves an average absorptivity over 90% within the 8~18 GHz frequency band at incident angles of 0°~45°, and within the 5~18 GHz band at incident angles of 0°~60° for TE and TM polarized EM waves, respectively. The 3-point bending simulation results show that, the CFDALS exhibits higher specific flexural strengths and stiffnesses along 2 directions of the CF arrays while achieving dual-polarized EM wave absorption. Incorporation of bidirectionally arranged CF prepregs into GF prepregs enhances the dual-polarized EM wave absorption performance and the bidirectional flexural performance of the CFDALS simultaneously. The work provides a novel solution for the EM wave absorbing and load-bearing integrated design for aircraft composite skin applications. [ABSTRACT FROM AUTHOR]

Triply periodic minimal surfaces (TPMS)‐based lattice structures exhibit improved mechanical and energy absorption properties compared to other lattices. Fused filament fabrication is the preferred approach for fabricating these structures and majority of the existing TPMS structures are manufactured using a single polymer. This study presents composite lattice structures that are reinforced with a second material. TPMS lattice structures are designed using MSLattice and modeled into cubical, cylindrical, bar, and dogbone geometries with relative density levels of 25%, 50%, and 75%. The structures are 3D printed with micro carbon fiber‐embedded nylon as the base matrix and fiberglass as the reinforcement. The structures are then characterized for mechanical properties and energy absorption as a function of density. The results show that the 25% relative density fiberglass‐reinforced structures exhibited similar or better properties compared to the 75% density structures without reinforcement. The mass normalized maximum force withstood by the 25% density‐reinforced cylinder was 1340 N/g compared to 1219 N/g for the 75% density non‐reinforced cylinder, clearly demonstrating the benefits of adding fiberglass. The 25% density cylindrical samples' energy absorption capacity increased on an average by 24.8% with the addition of fiberglass. The 25% density bar and dogbone samples' exhibited the highest improvement with the addition of fiberglass with an increase in stress capacity of 64.6% and 113%, respectively. These findings suggest that these lightweight composite TPMS structures can be a promising candidate for energy absorption applications such as the crumple zones in automobiles. Highlights: Gyroid structure modeled with 25%, 50% and 75% density in different geometries.Structures 3D printed with onyx fiber and reinforced with fiberglass.Reinforced cylindrical samples' energy absorption capacity increased by 24.8%.Bar and dogbone samples' maximum stress capacity doubled with reinforcement.Composite TPMS structures are good candidate for energy absorption application. [ABSTRACT FROM AUTHOR]

Composite laminates have found extensive application in various industries, and numerous studies have been conducted to investigate their behavior in flat sheet configurations. The present study aims to extend this research by examining the behavior of convex composite specimens subjected to high velocity impact (HVI), and comparing their energy absorption and failure area to that of flat sheets made of glass fibers. Additionally, we seek to investigate the influence of curvature diameter on the energy absorption and fiber failure percentage of the composite specimens. Four series of composite laminates with distinct geometries, comprising a flat specimen and three convex composite specimens, were fabricated with nine layers each and diameters of 10, 15, and 20 cm. All specimens were fully clamped and subjected to empirical gas gun impact tests at three different velocities of 200, 250, and 300 m/s. The velocity values before and after the impact were measured using velocity sensors, and the energy absorption of the laminates was computed. Of the tested composite specimens, those with smaller diameters and greater curvature exhibited reduced fiber damage percentage and increased energy absorption. Compared to the flat specimens made of glass fibers, the convex specimens with a diameter of 10 cm exhibited an energy absorption increase of approximately 47%, while the specimens with diameters of 15 and 20 cm showed approximately energy absorption increases of 42% and 7%, respectively. The results were confirmed through simulation using finite element software ABAQUS/Explicit. Highlights: Curved E‐glass laminates studied under high velocity impact which is done experimentally and numerically.Convexity increases energy absorption capacity of E‐glass reinforced epoxy composites.The results show that convexity can absorb more energy compared to flat panels.The damaged area of curved laminates are smaller than the flat one.The findings suggest that convexity can be a useful design feature for improving impact resistance in various applications. [ABSTRACT FROM AUTHOR]

Objective: To measure the flexural strength (FS) of bulk-fill resin composites and assess their long-term water absorption and solubility properties with and without the inclusion of short glass fibres. Methods: One resin composite, everX Flow with fibres, and four commercially available bulk-fill composites without fibres, namely, PALFIQUE, Activa, SDR Plus, and Filtek Bulk Fill One, were tested. Six specimens (2 × 2 × 25 mm) were fabricated for each material and stored in water for 1 day and 30 days to measure the flexural strength using a three-point bending test. To evaluate water absorption and solubility, circular disks measuring 15 × 2 mm (n = 5) were immersed in water for 60 days, and their weights were recorded periodically. After 60 days, the specimens were dried for an additional 21 days to determine solubility. Results: Flexural strength values ranged from 101.7 to 149.1 MPa. Significant distinctions were observed among the resin composites at the onset of the study (p < 0.05). The highest FS value was identified in everX Flow, while ACT exhibited the lowest (p < 0.05). However, the flexural strength values exhibited a significant decrease with increased storage time (p < 0.05), except for ACT, which demonstrated a noteworthy increase. Concerning water absorption and solubility, ACT displayed the highest absorption, while the range of solubility varied from −0.88 to 5.8 μg/mm3. ACT also had the highest solubility, whereas everX Flow exhibited negative solubility. Significance: The addition of short fibres, along with potential differences in matrix composition, enhanced the flexural strength of everX Flow. However, the substantial reduction in flexural strength observed in everX Flow and SDR following exposure to water corroborates the manufacturers' recommendation to apply a conventional resin composite cap on these materials. [ABSTRACT FROM AUTHOR]

In this paper, the energy absorption capacity of continuous fiber-reinforced thermoplastic auxetic structures is examined experimentally and the results compared with both numerical and analytical methods. To this extent, a 3 D printing technology of Fused Deposition Modeling (FDM) is implemented for fabricating the auxetic honeycombs and quasi-static compression test is conducted to extract the load-displacement behavior of the structure. Both hollow and foam filled lattice structures are tested, and the results revealed that the absorbed energy increased by 20% for PLA and 70% for PA specimens, when using foam. Finite element analysis is also performed using the explicit solver. The onset of failure is determined using the maximum stress criterion and VUSDFLD subroutine and the damage growth is modeled by decreasing the mechanical properties of the elements. The obtained results are in relatively good agreement with the experimental analysis. In addition, a theoretical formulation is developed and the probabilistic analysis is performed to draw the honeycomb failure design envelope, which is a practical tool for designing of various honeycomb configurations. The failure envelope shows that decreasing the strut angle increases the honeycomb failure load, however, the auxetic property of the structure decreases. [ABSTRACT FROM AUTHOR]

The low-velocity impact resistance of fiber metal laminates (FMLs) is investigated. FMLs with titanium alloy Ti-6Al-4V sheets and glass fiber/epoxy layers are fabricated using the hand layup technique, exhibiting the same total metal layer thickness. A drop tower is used to produce a low-velocity impact on the FMLs. FML with outermost metallic layers exhibits comparatively higher lateral spreading and interlayer delamination opening contrary to FML with more metallic layers. This is also observed in high-velocity impact. The low-velocity impact resistance of titanium-based FMLs seems higher than aluminum-based FMLs. This is also noticed in high-velocity impact for former and latter FMLs. [ABSTRACT FROM AUTHOR]

The crashworthiness performance and the deformation history of glass fiber reinforced epoxy (GFRP) composite over wrapped aluminum (Al) cylinders with induced holes were experimentally studied. Specimens were fabricated using wet wrapping by hand lay‐up process and tested under quasi‐static axial compression. Crashworthiness indicators that is, the initial peak load Fip, mean crush load (Fm), total absorbed energy (U), specific absorbed energy (SEA), and crush force efficiency (CFE) of the proposed cylinders were evaluated. The influence of the number of GFRP plies (P), the diameter (d), and number (N) of induced holes on the crashworthiness performance and the deformation history has also been identified. The experimental outcomes showed that the studied parameters have a significant effect on the crashworthiness performance and the deformation history. Increasing "P" increases Fip, Fm, U, and CFE while decreasing SEA. Inducing holes with "d" up to 8 mm reduces Fip, Fm, U, SEA, and CFE of GFRP/Al cylinders. After that the trend is reversed for all indicators except for Fip. GFRP/Al cylinders with "N = 2" exhibits lower Fip and higher Fm, U, SEA, and CFE than cylinders with "N = 1". Hybridization process and inducing holes could alter Al‐cylinders' failure mechanism. The relation between the crashworthiness indicators and the studied parameters has been constructed by response surface methodology (RSM) to be used by the engineering designers. Al‐P6‐d12‐N2 is recommended to be used in crash energy absorption applications that is, energy absorbing device in vehicles. [ABSTRACT FROM AUTHOR]

Several novel multi-layer lattice-web reinforced composite cylinders, consisting of glass fiber reinforced polymer (GFRP) face sheets and lattice webs, polyurethane (PU) foam core and clay ceramsite filler, were proposed and manufactured using a vacuum assisted resin infusion process (VARIP) method. A series of quasi-static lateral compressive experiments were carried out to investigate the feasibility of the proposed cylinders. For both the hollow composite cylinders and ceramsite filling composite cylinders, the bearing capacity and energy absorption performance can be significantly improved with the use of multi-layer lattice-web layouts. Among the proposed three types of lattice-web layouts, the double-layer dislocated lattice-web layout made the composite cylinder exhibit the greatest specific energy absorption (SEA) performance and can be chosen as an optimal configuration. Furthermore, numerical models were established using LS-‍DYNA software to simulate the large deformation of the composite cylinders with double-layer dislocated lattice-web layout. Based on the numerical models, parametric analysis was carried out to discuss the effects of various parameters on the crushing response of the composite cylinders. Generally, using thicker GFRP material or higher radial lattice web can make the composite cylinders present an increased likelihood of brittle failure. However, filling ceramsite can not only make them exhibit plastic deformation characteristics but also facilitate the full utilization of various components. [Display omitted] • Composite sandwich cylinders are appealing to anti-collision facilities but existing drawbacks. • Multi-layer lattice-web reinforced composite cylinders have great energy absorption performance. • Double-layer dislocated lattice-web layout could be conductive to the protection of ship and bridge. • Filling ceramsite makes the composite cylinder exhibit an increased likelihood of plastic behavior. [ABSTRACT FROM AUTHOR]

In this work, we fabricated and systematically investigated the mechanical and microwave absorption properties of multi‐walled carbon nanotube (MWCNT)—glass fiber (GF)—epoxy composites. The composites showed high electromagnetic (EM) wave absorption performance in a wide frequency range. The maximum reflection loss of the composites can reach to −48 dB at 24.5 GHz. The EM wave absorption of the composites strongly depends on MWCNT and GF contents and can reach to ~70% at 26.5 GHz; further, such dependence is peculiar, contradicting to the conventional wisdom, due to high density interfaces in the materials, which lead to multiple scatterings and multiple absorptions of EM waves. The tensile strength of the composites was enhanced to ~427 MPa with ~74 wt% GFs, that is comparable to that of commercial Al alloy 6061 (~300 MPa, but not much EM wave absorption). The composites have the potential as multifunctional microwave absorption and low‐weight structural materials without a need of additional coating. [ABSTRACT FROM AUTHOR]

Herein, the enhancement of the mechanical properties of microwave absorption composites, multiwalled carbon nanotubes (MWCNTs)–epoxy with various MWCNT loadings, using glass fiber (GF) reinforcement is focused upon. The tensile strength, morphologies, dielectric permittivity, and electromagnetic (EM) wave absorption properties (in a frequency range from 1 to 26 GHz) of the composites are investigated. The tensile strength of the composites is enhanced to about 400 MPa, which is comparable with that of commercial aluminum alloy 6061 (about 300 MPa), whereas the tensile strength of the pristine MWCNT–epoxy composite is around 15 MPa. The mass density of the MWCNT–epoxy–GF composites herein is found to be around 1.6 g cm−3, whereas aluminum alloy 6061 has a mass density of ≈2.7 g cm−3. In addition, the MWCNT (9 wt%)–epoxy–GF composite presents a strong EM wave absorption in a wide frequency band from 14 to 26 GHz, whereas aluminum alloys do not have much EM wave absorption. The high microwave absorption together with the enhanced mechanical strength of the composites provides a multifunctional potential for some applications. [ABSTRACT FROM AUTHOR]

This paper presents the results of an experimental program to determine the properties of glass fiber reinforced geopolymer mortar which is a mixture of fly ash, alkaline liquids, fine aggregates, and glass fibers. The effects of inclusion of glass fibers on density, compressive strength, splitting tensile strength, absorption and sorptivity of hardened geopolymer composite (GPC) was studied. Alkaline liquid to fly ash ratio was fixed as 0.33. NaOH and NaSiO3 solutions were used as alkaline liquids for activation of fly ash. The alkaline liquid combination ratio of 2.5:1 were used for Na2SiO3:NaOH. Glass fiber was added to the mixes in 0.2%, 0.4%, 0.6%, 0.8%, 1.0% and 1.2% by volume of mortar. A curing regime of 48 hours with 60 °C temperature was applied. The experimental results indicated that inclusion of the glass fibers resulted in a decrease in the workability, yet, an improvement in compressive strength and splitting tensile strength of fly ash based GPC was obtained by increasing the fiber content. However, the inclusion of glass fiber did not indicate a remarkable change in the water absorption and sorptivity of GPCs. [ABSTRACT FROM AUTHOR]

Electromagnetic functionalization of mechanical lattice is an important method to integrate mechanical and electromagnetic properties into one structure with effective load bearing and broadband microwave absorption. Herein, the gradient lattice metastructure (GLM) is fabricated by dielectric-magnetic lossy nano composite strengthened by carbon fiber and glass fiber reinforced polymer. A large mutation genetic algorithm is developed to optimize the GLM with fine convergence property. Several large mutation modules are incorporated into the program to speed up the optimization process and improve global convergence. The measured −10 dB absorption bandwidth covers 2–5 GHz and 6.5–17.3 GHz while −9.5 dB absorption bandwidth covers 2–17.3 GHz. The oblique incident broadband absorption is achieved from normal incidence to the grazing incidence of 85° in traverse electrical (TE) and traverse magnetic (TM) polarization. Gradient lattice design is effective to overcome systemic oblique incident absorption deterioration originating from enhanced tangential electric field intensity in large incident angles. The nominal tensile strength of GLM reaches 108.4 MPa with maximum flexural load of 1.83 kN. The high electromagnetic and mechanical properties are achieved simultaneously by electromagnetic functionalization of mechanical lattice. [Display omitted] [ABSTRACT FROM AUTHOR]

We thoroughly and critically review studies reporting the real (refractive index) and imaginary (absorption index) parts of the complex refractive index of silica glass over the spectral range from 30 nm to 1000 mum. The general features of the optical constants over the electromagnetic spectrum are relatively consistent throughout the literature. In particular, silica glass is effectively opaque for wavelengths shorter than 200 nm and larger than 3.5-4.0 mum. Strong absorption bands are observed (i) below 160 nm due to the interaction with electrons, absorption by impurities, and the presence of OH groups and point defects; (ii) at ~2.73-2.85, 3.5, and 4.3 mum also caused by OH groups; and (iii) at ~9-9.5, 12.5, and 21-23 mum due to Si?O?Si resonance modes of vibration. However, the actual values of the refractive and absorption indices can vary significantly due to the glass manufacturing process, crystallinity, wavelength, and temperature and to the presence of impurities, point defects, inclusions, and bubbles, as well as to the experimental uncertainties and approximations in the retrieval methods. Moreover, new formulas providing comprehensive approximations of the optical properties of silica glass are proposed between 7 and 50 mum. These formulas are consistent with experimental data and substantially extend the spectral range of 0.21-7 mum covered by existing formulas and can be used in various engineering applications.

Purpose:The effect of water sorption on the flexural strength and flexural modulus of three fiber-reinforced composites was studied. Materials and Methods:Bar-shaped specimens of each material were prepared according to the manufacturers' instructions. The flexural strength and modulus of each specimen were tested after the specimens were immersed in distilled water for 1, 7, 60, and 180 days. SEMs were taken to examine the mode of failure. The volume percentage of fiber content of each fiber-reinforced composite was experimentally estimated. Results:The ascending order of flexural strength and modulus among the materials was generally: FibreKor < Stick < Vectris. The flexural strengths of Stick and FibreKor specimens at 1 and 180 days were not significantly different. Although the 180-day Vectris specimens possessed significantly lower flexural strength than the 1-day specimens, the flexural strengths of Vectris specimens at 1, 7, 60, and 180 days remained significantly higher than those of Stick and FibreKor. The difference in flexural modulus for each fiber-reinforced composite related to the duration of water immersion was not significant. Conclusion:Water immersion affected the flexural strengths of the three composites to a different degree but did not affect their flexural moduli significantly. For each duration of water immersion, the flexural property of the fiber-reinforced composite, in ascending order of significant difference, was: FibreKor < Stick < Vectris. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to determine the dimensional accuracy and water sorption of a denture base polymer that was reinforced with glass fibers in continuous unidirectional and woven form in different weight fractions. Materials and Methods: Ten rhombic brass plates were prepared with reference points, and 70 heat-cured denture base polymer specimens were produced using these brass models. Ten of 70 were used for controls, and 60 were reinforced with glass fibers in continuous parallel and woven form. The dimensional changes of polymer and fiber-reinforced composite specimens after processing, drying for 4 days at 37°C, and storage in 37°C water for 90 days were calculated by the change of the distance vector. The measurements were made between the reference points on the specimens and were compared with those on the brass model at 4 different stages. The water sorption calculations were made at 10 different time intervals on 70 specimens, which were immersed in a 37°C distilled water bath and weighed. Results: The polymerization shrinkage and water sorption of denture base polymers is lower when the specimens are reinforced with glass fibers in continuous unidirectional and woven form. The highest fiber content showed the smallest dimensional change (0.069 mm, or 0.25%), and the unreinforced group showed the largest change (0.139 mm, or 0.54%). Water sorption occurred mainly during the first 14 days. Conclusion: As the fiber content increases, the dimensional change and water sorption decrease. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Patterned GFRP superhydrophobic surface was fabricated by laser texturing. • Achieve over 88% of the underwater acoustic absorption from 50 kHz to 250 kHz. • High acoustic absorption ascribes to the multiple interface scattering effect. Abstract Underwater acoustic absorption metasurfaces (UAAMs), featured with artificial periodic unit cells as acoustic micro-absorbers, are crucial for the enhancement of the underwater stealth, energy transition, sonar detection, etc. How to implement the acoustic metasurfaces for practical engineering applications requires the support of efficient manufacturing techniques. Here we present a simple way of laser texturing for fabrication of the patterned superhydrophobic surface on glass fiber reinforced plastic (GFRP). Unlike the traditional acoustic absorbing material whose thickness should match the corresponding wavelength, the laser textured superhydrophobic micro-grooves have thickness less than the absorption sound wavelength by 2–3 orders of magnitude but promisingly demonstrate over 88% of the underwater incident acoustic power absorption from 50 kHz to 250 kHz. The physical mechanism of the UAAM ascribes to the multiple interface scattering effect induced by the air layer between water and superhydrophobic micro-nano structures. [ABSTRACT FROM AUTHOR]

Abstract The present paper aims to provide further understanding of the low-velocity impact behaviour of glass fabric cloth reinforced epoxy composite panels embedded with wire nets (WN-GF/epoxy). WN-GF/epoxy hybrid panels with six layer modes were manufactured by vacuum-assisted injection process. Low-velocity impact tests with various incident velocities were performed, and the perforation thresholds of the designed specimens were found out. Scanning electron microscope was carried out to study the microstructure of the composites after impact. Experimental results show that perforation threshold velocity of the specimens appears a bi-linear increasing tendency with increase of the embedded wire nets, and the increase ratio has an inflection point. Damage pattern observation results show that the enhanced energy abortion ability is mainly due to the increased delamination area of the specimens during the impact events. 3D finite element models were developed in ABAQUS/Explicit to analyze the damage behavior of WN-GF/epoxy composites, and a user subroutine was compiled. The contact load and change of kinetic energy absorption characteristics have been used to validate the finite element results. The penetration process and damage modes of WN-GF/epoxy interply hybrid composites under low-velocity impact are further discussed with the assistant of numerical results. [ABSTRACT FROM AUTHOR]

Highlights • The seawater diffusivity reduced by 15% of the nanocomposite. • The flexural strength improved by 15% of the nanocomposite. • The ILSS of the nanocomposite has increased by 23% as compared to neat epoxy GFRP composite. • No significant change in glass transition temperature has observed between neat epoxy and nano-composite. Abstract Nano-fillers are embedded with epoxy polymer matrix of glass fiber reinforced polymer (GFRP) composites to enhance the mechanical properties. In the present investigation, the nano-TiO 2 particles of different concentrations was mixed with the epoxy polymer matrix to improve the mechanical properties. GFRP nano-composites fabricated by hand lay-up method and subsequently immersed in a seawater bath at 70 °C for 40 days. The seawater diffusivity, flexural, and interlaminar shear strength of the composites were evaluated and compared between themselves. The result revealed that with the addition of 0.1 wt.% of the nano-TiO 2 particles into the epoxy polymer matrix, seawater diffusivity improved by 15%. However, flexural and interlaminar shear strength of seawater aged nanocomposites is increased by 15% and 23% respectively. The fractured surface of the broken samples has been analyzed through field emission scanning electron microscope (FESEM) to establish the structure–property co-relationship. [ABSTRACT FROM AUTHOR]

This study focuses on the effect of metal layer distribution in glass fibre reinforced aluminium laminates (GLARE) subjected to low velocity impact. Four GLARE variants specimens were considered in which the metal layers of different thicknesses were placed at various positions in the layup while keeping the same total metal layer thickness. Experiments and Finite element (FE) analysis were performed to understand the behaviour of the GLARE specimens. A user written material subroutine VUMAT which incorporates Hashin failure criteria along with Puck's action plane concept were used to predict the response of the composite layers. The damage was evolved for each failure mode using the exponential damage evolution law. Interface delamination between the layers was initiated by cohesive surface behaviour which includes the friction effect between the plies. It was found that placement of thinner metal layer on top of the laminate and its distribution inside the layup lowers the impact resistance of GLARE. Moreover, the patterns of delamination are also affected by the placement of metal layer within the laminates. It was further shown that the propagation direction of delamination is governed by the fibre direction of lower ply of the interface. [ABSTRACT FROM AUTHOR]

In the present research, synthesis and characterization of hybrid bamboo/glass fiber reinforced polyester (PE) matrix-based composites through compression moulding technique was fabricated and characterization is done. Seven different combinations of composite plates were prepared with the fiber alignment of 30o and 60 o in a plain weaved mat form. Experimental results show that when hybrid fibers combined with polyester matrix, mechanical properties such as tensile strength, flexural strength, impact strength, hardness and water absorption tests of the matrix increases the superior specific strength and modulus but have a lower failure strain compared to other combinations and then pure bamboo or pure glass fiber possess decrease in strength compared to hybrid combinations. Thermal and Morphological investigation of the pure bamboo or pure glass fiber and hybrid fiber fiber-reinforced polyester composites have also been carried out. The results found show that application of these fibers as probable reinforcing materials in bio-based polymer composites. [ABSTRACT FROM AUTHOR]

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Since practical microwave absorption materials and structures are highly pursued in broad industry, traditional hybrid materials generally suffer from poor mechanical strength and narrow effective microwave absorption bandwidth. In this work, we utilized a graphene-based fabric as the effective microwave absorption layer, followed by sandwiching into glass fiber and carbon fiber cloths, to fabricate practical composite structures. For further extending the effective absorption bandwidth, surface-patterned structures were employed to promote the microwave absorption performance in X and Ku bands. The fabricated sandwich structure and SA exhibit > 90% absorption in 9.8-18 and 8-18 GHz, respectively. With the presence of epoxy matrices, both the mechanical strength polymeric sandwich and surface-patterned structures hold high efficiency in broadband absorption. For understanding the effects of the material and structure effect on the performance, various surface conditions were tuned to tailor the performance, and the corresponding mechanism was discussed. [ABSTRACT FROM AUTHOR]

Carbon fibers (CFs) have been widely used as absorbing materials for radar cross section (RCS) reduction. Here, an alternative approach for CFs is proposed to achieve the same goal and has been performed by the glass fabric composites loaded with a small number of CFs. The reduction mechanism of our proposal is phase cancellation instead of absorption. Two prototypes in chessboard and random patterns are analyzed numerically and measured experimentally. The short CF yarns are designed as the patterned configurations and embedded into the composite surface layers. It is demonstrated that the proposed composites allow for remarkable suppressing of the specular scattering over a broad frequency band. The designed RCS reduction level more than 10 dB covers the frequency range from 8.7 to 19.2 GHz, while the overall thickness is 2.7 mm. The proposed composites are of a simple configuration and robust for the defects. It is also believed that the study of this work can be easily extended to the curved surfaces. [ABSTRACT FROM AUTHOR]

This paper focuses on the experimental characterization and modeling of the impact behavior of a multi-functional dual core sandwich panel designed for the rehabilitation of hydroelectric turbines. The studied sandwich panel consists of glass fiber reinforced epoxy (GFRE) facesheets and a dual core composed both of alumina trihydrate-filled epoxy (ATH/epoxy) and extruded polystyrene foam (XPS). Low-velocity impact tests are conducted at different impact energies to take into account the presence of debris in the water flow. A 3D numerical model is developed to simulate the impact tests and particularly the energy distribution within the sandwich constituents. A good correlation is achieved between the experimental data and numerical predictions. The dual core sandwich construction placed on a rigid foundation undergoes both local and global deformation under impact loading. The experimental results show that for the tested impact energy range, the sandwich panel absorbs approximately 50% of the impact energy. Although the top facesheet and the ATH/epoxy core govern the initial impact behavior, the recoverable compression deformation of the XPS foam core is the major energy absorption mechanism. This statement is well supported by the numerical simulation. [ABSTRACT FROM AUTHOR]

Spontaneous imbibition of a liquid into glass-fiber wicks is modeled using the single-phase Darcy's law after assuming a sharp flow-front marked by full saturation behind the front occurring in a transversely isotropic porous medium. An analytical expression for the height of the wicking flow-front as a function of time is tested through comprehensive experiments involving using eight different wicks and one oil as the wicking liquid. A good fit with experimental data is obtained without using any fitting parameter. The contact-angle is observed to be important for the success of the model-lower contact angle cases marked by higher capillary pressures were predicted the best. The proposed model provides a nice upper bound for all the wicks, thereby establishing its potential as a good tool to predict liquid absorption in glass-fiber wicks. However, the sharp-front model is unable to explain region of partial saturation, thereby necessitating the development of part II of this article series (Zarandi and Pillai, Spontaneous Imbibition of Liquid in Glass fiber wicks. Part II: Validation of a Diffuse-Front Model. AIChE J, 64: 306-315, 2018) using Richard's equation. © 2017 American Institute of Chemical Engineers AIChE J, 63: 294-305, 2018 [ABSTRACT FROM AUTHOR]

Replacing external metallic wall of refrigerated vehicles has been on the front burner in many published works as weight of the metallic insulated panel continues to pose a challenge on refrigeration unit and environment. As a follow-up to this problem statement, five (5) composite materials were fabricated as replacement options for metallic external sheet for refrigerated vehicles. The key study of this paper is to investigate the moisture absorption and thickness swelling tendencies of these composite specimens as these properties determine the suitability of these materials for refrigerated wall. Part of the methodology adopted in the manufacturing of these composites were based on fibre loading and orientation in the composite panel. Key findings from this experiment shows that the absorption behaviour of composites at 30° and 60° was consistent until 60 hours duration of immersion before a significant disparity was observed. In addition, G30E (30% reinforced glass fibre in the epoxy composite) was more resilient to moisture attack as a result of enhanced fiber content. The implication of the study is that G30E reinforced composite material could be adopted as external wall of food transport system because of its lower thickness swelling and water absorption properties. [ABSTRACT FROM AUTHOR]

Layered gypsum-based composites for S-band electromagnetic (EM) wave absorption were designed and fabricated by introducing carbon black (CB) coated glass fiber grids, and the EM wave absorption properties were measured by arching testing method. The results indicate that the EM wave absorption can be greatly improved by the glass fiber grids, and the absorption properties can be influenced by periodic size, sample thickness and CB content. The composites with double layer glass fiber grids exhibit wider bandwidth and lower reflection loss due to the formation of gradient impedance. Moreover, the design of double layer matrix can make the absorption peaks shift to lower frequency, which can be attributed to the multiple scattering and reflections of incident wave caused by expanded perlites. The reflection loss of the prepared composites can be less than −10 dB in 2.2–3.63 GHz. This gypsum-based composites can be a candidate to prevent S-band indoor EM radiation. [ABSTRACT FROM AUTHOR]

Purpose This study aimed to investigate the collective effects of bending load and hygrothermal aging on glass fibre-reinforced plastics (GFRP) due to the fact that stress and water absorption is inevitable during GFRP applications. Design/methodology/approach The water boiling method was used to study the moisture absorption, desorption behaviour and evaluate the performance of GFRP laminates under loading in this article. The moisture diffusion of laminates is characterized in three aging conditions (25°C, 45°C and 65°C water), along with three levels of bending load coefficients (0, 0.3 and 0.6). The moisture diffusion coefficients are determined through the curve fitting method of the experimental data of the initial process, based on the Fickian diffusion model. Moreover, the laminates' performance is further discussed after adequate environmental aging and loading. Findings It was found that moisture absorption is promoted by the presence of bending load and boiling during this study. The absorption diffusion coefficient and moisture equilibrium content of the specimens increased with an increasing loading ratio and temperature. The bending strength of the laminate varied according to a contrary trend. Furthermore, the desorbed moisture content is found to be much higher after higher levels of bending load because it is harder to desorb the moisture in the interfaces and micro cracks. Research limitations/implications Collective effects of bending load and hygrothermal aging promote the absorption and result in accelerating property degradation of GFRP. It is significant to focus on these effects on the failure of GFRP. Originality/value A novel unit was designed to simulate the various loading acted on containers in this work. [ABSTRACT FROM AUTHOR]

To evaluate the electromagnetic (EM) absorption and shield of magnetic composite sheet, we prepared the FeCoNi coated glass fibers filled in composite sheet. The FeCoNi was coated by electroless plating on glass fiber as a filler. The coated FeCoNi found that consist of mixtures of bcc and fcc phase. The magnetization and coercivity of coated FeCoNi are about 110 emu/g and 57 Oe, respectively. The permittivity and permeability of the FeCoNi composite sheet were about 21 and 1, respectively. Power absorption increased 95% with the increment of frequency up to 10 GHz. Inter-decoupling of this composite sheet showed maximum 30 dB at around 5.3 GHz, which is comparable to that of a conductive Cu foil. Shielding effectiveness (SE) was measured by using rectangular waveguide method. SE of composite obtained about 37 dB at X-band frequency region. [ABSTRACT FROM AUTHOR]

A non-magnetic broadband radar absorbing structure (RAS) composed of glass fiber composite and multilayer frequency selective surface (FSS) films was designed, with subsequently optimizing and manufacturing for radar absorbing and mechanical investigations. The results revealed that the proposed RAS exhibited −10 dB absorption from 8 GHz to 18 GHz at thickness of 3.5 mm, with a substantially broadened absorption bandwidth via dual absorption peaks. Due to the embedment of FSS films, the thermal-elastic stability of the structure was slightly enhanced while the flexural and impact resistance performances decreased owing to the effect of weak interface between the FSS films and composite laminates. In fact, the tensile performance of RAS, which was important for application under load bearing conditions, was not significantly compromised. The failure morphologies of the RAS were analyzed by scanning electron microscope (SEM) and the fracture mechanism was discussed. [ABSTRACT FROM AUTHOR]

In this study, experimental and finite element analyses of perforation behaviour of unidirectional glass fiber reinforced cross ply laminate have been presented, considering different projectile nose shapes, incidence velocities, incidence angle and laminate thickness. A pneumatic gun was used to propel 52 g steel projectile of diameter 19 mm at incidence velocity up to 300 m/s, where the projectiles are having different nose shapes such as ogival, conical, spherical and blunt. The target plate of size 140 mm × 140 mm and thickness 3.3 and 6.6 mm were made by unidirectional (UD) glass fiber with orientation (0°/90°/90°/0°) and (0°/90°/90°/0°) 2 respectively. A three dimensional finite element model is developed using Lagrangian, eight nodded brick element in ANSYS/AUTODYN, v14.5. The elastic properties of GFRP laminate is obtained from tensile tests in Universal Testing Machine in the civil engineering laboratory of IIT Roorkee, India. The velocity and acceleration-time histories of projectile along with ballistic limit, energy absorption and damage pattern in target plate are presented. The results obtained from numerical simulation are having good correlation with the corresponding experimental values and many new interesting results are also generated especially for oblique impact. [ABSTRACT FROM AUTHOR]

A high spike force at the beginning of impact and the load fluctuations caused by unstable plateau deformation are disadvantages to avoid for impact resistance structures. Lightweight glass fiber-reinforced polypropylene composite hierarchical cylindrical structures (namely GFRP-CHCS, with a relative density of less than 0.1) have the potential to achieve low initial force and high crushing force efficiency under dynamic conditions. This work explores the drop-weight impact behaviors and energy absorption capacity of GFRP-CHCS. Deformation modes, failure conditions, and impact load history responses are discussed. Results showed that GFRP-CHCS has no initial load peak and achieves gentle response curves under the low-velocity impact when the load speed is less than 10 m/s. Among the experiments where the impact energy was beyond the range of static energy absorption, more than 94% of the impact energy was absorbed or dissipated when the impact energy ranged from 200 J to 300 J. After unloaded, GFRP-CHCS maintained good integrality and recovered a significant deformation which was over 93% initial structural height. With ideal isotropic material properties, numerical and theoretical predictions were conducted regarding the loading velocity effects on structural deformation mode and mean impact response force. This work utilized a thermoplastic composite consisting of GFRP face sheets and polypropylene core. The results have reference significance for the anti-impact design of thermoplastic composite hierarchical structures. [Display omitted] • Introduce GFRP-CHCS to offer low initial impact force and a stable deformation process. • Damage and energy absorption mechanism of GFRP-CHCS under low-velocity impact was experimentally revealed. • Theoretical and numerical predictions on impact mean crushing force are proposed and validated. [ABSTRACT FROM AUTHOR]

• The mechanism of impurity absorption and heterophase inclusion in Ge-As-S glass was investigated. • Heterophase inclusions in Ge-As-S glass can be effectively suppressed by dynamic distillation and melting at the optimized melting temperature. • The average loss of purified fiber and unpurified one is 1.86 dB/m and 2.87 dB/m, respectively. About 1 dB/m decrease in the loss is due to the absence of the visible heterophase inclusion particles in the glass. Strong absorption from the impurities and background scattering induced by heterophase inclusions are major issue in the applications of Ge-As-S glass in mid-infrared (MIR). Here, we report that, the absorption of impurities sourced from raw materials can be removed effectively by oxygen getters and hydrogen getters under static vacuum distillation, leading to almost disappearance of the absorption at 3.11 μm due to S H, <4.08 ppm at 4.01 μm due to S H and < 11.03 ppm at 7.5 μm due to As-O, respectively, in Ge 10 As 28 S 62. The impurities of H 2 O and CO 2 can be further eliminated to near zero by dynamic distillation. On the other hand, the heterophase inclusions, originating from raw materials of sulfur, arsenic and germanium, the silica-container and deoxidizer of Mg, can be eliminated thoroughly by dynamic distillation and optimized melting temperature. We draw the fibers using unpurified and purified glasses and found that, comparing with the fiber loss of 2.87 dB/m at unpurified glass, the optical loss can be decreased to about 1.86 dB/m in purified glass without any visible particles or heterophase inclusions. All the results pave the way of developing low loss Ge-As-S glass fiber for high power laser delivery. [ABSTRACT FROM AUTHOR]

In this study, hybrid composite materials were prepared from combination of modified coconut wood flour (MCWF) and glass fiber (GF) as fillers, and waste polypropylene (WPP) as matrix. The coconut wood flour (CWF) was modified by 18% sodium hydroxyde solution to reduce its hydroxyl group. The interfacial adhesion between the non-polar waste polypropylene matrix and the polar fillers could be enhanced by using maleic anhydride-gpolypropylene (MAPP) which was synthesized from the refluxed reaction of maleic anhydride, polypropylene, xylene and benzoyl peroxide at 135°C. MAPP and GF composition were made constant at 2 wt. % and 10 wt. %, respectively and MCWF composition was varied from 10 - 40 wt.%. Mixing process was carried out in an extruder at 180oC and the samples were then molded in a hot press machine. The impact strength, water absorption, and filler volume fraction analysis were investigated. The results showed that addition 30 wt.% of MCWF and 10 wt.% of MAPP can elevate the impact strength of the composite. The study also revealed that water absorption of the composite has reduced with the utilization of MAPP. As comparison, composite without MAPP, no fillers and using one type of filler were also prepared. These results were also supported by Fourier Transform Infra - Red (FTIR) and Scanning Electron Microscopy (SEM) analysis. [ABSTRACT FROM AUTHOR]

A multifunctional hybrid material class in the form of a sandwich panel has been developed towards the combined optimization of mechanical and electromagnetic absorption performance. The faces of the panel are made of glass fibre reinforced epoxy composites and the core is made of carbon nanotube reinforced polymer foam filling a metallic honeycomb. The different processing strategies and options tested to fabricate the core material are described as well as the associated scientific and technological issues. The most efficient processing route is by foaming the nanocomposite with a chemical foaming agent directly inside the honeycomb. This route offers a good surface finish and the operation can be achieved in one step. But, in order to produce large panels with a semi-continuous process, thermo-mechanical insertion of the foamed nanocomposite with supercritical CO2 can be more suitable. The characterization of the electromagnetic absorption of the panels produced by different routes shows that the performance is not much sensitive to processing defects making possible upscaling to mass production. [ABSTRACT FROM AUTHOR]

Water absorption and aging behaviors of fiber reinforced polymerized poly (cyclic butylene terephthalate) (GF/pCBT) composites are investigated. We coated nano-silica on glass fiber surface by physical vapor deposition (PVD) method. Subsequently, we immersed pCBT composites reinforced with nano-treated/untreated fibers in 25 °C and 60 °C distilled water until their saturated moisture. We also exposed some specimens in various hydrothermal aging environments. We tested the mechanical performance of these test specimens and found that the mechanical performance of both pCBT cast and GF/pCBT composites reduces obviously after water absorption and hydrothermal aging. However, nano-silica modified fiber reinforced composites have higher remaining strength than GF/pCBT. Scanning electron microscope (SEM) is used to study the microscopic phase and nanoparticle modified mechanism, and better interface characteristic between fibers and matrix is observed. [ABSTRACT FROM AUTHOR]

In this paper, the results of experimental and numerical simulation of low velocity impact process have been carried out to investigate energy absorption of composite sandwich panels with 3D woven fabrics of glass fibers and epoxy resin. For this purpose, diagrams of force-displacement of the quasi-static and quasi-dynamic impact tests were studied. For the finite element simulation, Sandwich panel is considered as a composite material with anisotropic elastic properties. In this simulation, Hashin's damage criteria have been used to model the fracture mechanics. The energy absorption in quasi dynamic test is greater than the quasi static test. Comparison of numerical and experimental shows good agreement between the results. [ABSTRACT FROM AUTHOR]

Glass fiber-reinforced plastic composites (GFRPs) are often suffered to impact loadings; it is essential to improve its damage-resistant properties and understand the energy absorption mechanisms. In this work, the low-velocity impact behaviors of GFRPs were investigated in consideration of epoxy resins modified with 0, 0.4, and 0.75 % multi-walled carbon nanotubes (MWCNTs) by weight content and pre-stretched fabric at 0, 1.27, and 2.47 kg weight. In comparison with pure GFRPs sample, MWCNT-modified specimens are effective in improving the impact resistance under impact energies at 9, 16, and 22 J in terms of reduced damage factor and enhanced perforation threshold. Microscopic fractographic analysis indicated that the incorporation of MWCNTs in epoxy matrix offered additional mechanisms through breakage, bridging, and pull-out of carbon nanotubes to favor load transfer effect, prevent crack propagation, and thus dissipate more energy. The dynamic thermo-mechanical analysis proved that MWCNTs improved the storage modulus and glass transition temperature of the composites. In addition, the pre-stretched GFRP composites showed more impact resistant than the non-stretched ones through instant load transfer effect. [ABSTRACT FROM AUTHOR]

The main objective of the present study is to introduce a new fiber metal laminate (FML), formed by sandwiching a 3D fiberglass fabric in between thin sheets of magnesium alloy. In particular, the low-velocity impact (LVI) response and failure modes of this new FML composite are investigated experimentally and computationally. In addition, to gain a more comprehensive understanding of the response of the FML, its performance is compared against those of conventional FMLs, made with various layers of biaxial woven fabrics in place of the 3D fabric. The failure modes of the specimens are characterized based on the quantitative measurements of shape, type, and extent of damage on the FMLs’ constituents. The impact characteristics of all panels are further examined by characterizing and comparing their energy absorption capacity, residual deformation and maximum deformation due to LVI. The characteristics of the new 3D glass fabric are specifically discussed, and its positive attributes and limitations, in comparison to woven fabrics, are highlighted. The results would reveal that FML made by the 3D fabric exhibits outstanding impact absorption capacity; however, their impact energy resistance is lower than FMLs formed by woven fabrics. Moreover, as a major part of this study, a finite element analysis (FEA) framework is constructed, using the commercial finite element code ABAQUS, in order to simulate the response of such complex structures. Good agreement between the experimental and computational results demonstrate that the simulation framework can be further used to optimize the configuration of FMLs for different loading situations. [ABSTRACT FROM AUTHOR]

This paper reports the effect of sulfuric acid solution absorption on the dynamic mechanical properties of glass fiber reinforced polyester composites. An experimental device is presented that allows the effect of changes of environment and temperature on both the diffusion coefficient and the maximum moisture content to be measured. The results indicate that increased temperature raises both the diffusion coefficient and the maximum absorbed moisture of all the composite materials used in this study. Moreover, it has been noted that specimens exposed to higher temperature absorb much more water than those held at low temperature. The dynamic mechanical properties of glass fiber reinforced polyester were found to be highly affected by the presence of absorbed solvents in the specimen and increases in temperature. A fractographic study has been conducted using a scanning electron microscope of the surfaces of specimens broken by tensile testing. Observations indicate that increased immersion time increases the deterioration of the fibre/matrix interface. [ABSTRACT FROM AUTHOR]

Macro and microstructural damage was studied in typical glass fibre-reinforced polymer laminates with two types of coating systems – (a) isophtalic gel coat: pure or mixed with SiO2 nanoparticles 5 wt% (5%N) or 10 wt% (10%N) and (b) a two-layer coating system: urethane-modified vinyl ester-based gel coat and additional polyester barrier coat layer. Accelerated tests were performed at 50℃ for 50 days for specimens with nanoparticle-modified gel and for the specimens with or without a barrier coat. Long-term ageing behaviour at 23℃ was assessed for the two-layer systems. Nanoparticle-reinforced specimens (10%) showed some advantage over ‘barrier coat systems' in terms of blister incubation time (16 and 13 days, respectively), while for 5% and 0% nanoparticles, blister incubation times were 3 and 7 days, respectively. Round and/or acicular blisters were observed on the examined surfaces. The varying size, shape and distribution of blisters was illustrated by macro and micrographs showing various failure modes associated with surface blisters. [ABSTRACT FROM AUTHOR]

Glass fibers reinforced polymer composites have been prepared by various manufacturing technology and are widely used for various applications. Initially, ancient Egyptians made containers by glass fibers drawn from heat softened glass. Continues glass fibers were first manufactured in the 1930s for high-temperature electrical application. Nowadays, it has been used in electronics, aviation and automobile application etc. Glass fibers are having excellent properties like high strength, flexibility, stiffness and resistance to chemical harm. It may be in the form of roving’s, chopped strand, yarns, fabrics and mats. Each type of glass fibers have unique properties and are used for various applications in the form of polymer composites. The mechanical, tribological, thermal, water absorption and vibrational properties of various glass fiber reinforced polymer composites were reported. [ABSTRACT FROM AUTHOR]

Highly sensitive absorption measurements on various samples may be carried out by Fiber-optic Evanescent Wave Spectroscopy (FEWS) in the mid-IR. Such measurements have already been done on solids, liquids and gases, using chalcogenide glass fibers or crystalline fibers. Segments of crystalline AgClBr fibers may be used as sensors of much higher sensitivity if their middle sections are pressed to form flat waveguides. We carried out measurements on micrograms of insoluble or slightly soluble particles in water, when they sedimented on the flattened parts of such sensors. Measurements were also carried out on few micrograms of dry particles that had been pressed onto the flattened parts. Flattened fiber sensors may therefore be used for measurements on micrograms of particles and they can be used for identifying the chemical nature of particles of organic, inorganic or biological materials and for studying their properties. The FEWS method, based on flattened mid-IR fiber sensors, is simple, inexpensive and does not require sample processing. It would be useful for measurements on very small quantities of particles for biomedical applications, for environmental protection, for drug enforcement agencies and for homeland security. [ABSTRACT FROM AUTHOR]

Abstract: A generic optical biosensing strategy was developed that relies on the absorbance enhancement phenomenon occurring in a multiple scattering matrix. Experimentally, inserts made of glass fiber membrane were placed into microplate wells in order to significantly lengthen the trajectory of the incident light through the sample and therefore increase the corresponding absorbance. Enhancement factor was calculated by comparing the absorbance values measured for a given amount of dye with and without the absorbance-enhancing inserts in the wells. Moreover, the dilution of dye in solutions with different refractive indices (RI) clearly revealed that the enhancement factor increased with the ΔRI between the membrane and the surrounding medium, reaching a maximum value (EF>25) when the membranes were dried. On this basis, two H2O2-biosensing systems were developed based on the biofunctionalization of the glass fiber inserts either with cytochrome c or horseradish peroxidase (HRP) and the analytical performances were systematically compared with the corresponding bioassay in solution. The efficiency of the absorbance-enhancement approach was particularly clear in the case of the cytochrome c-based biosensor with a sensitivity gain of 40 folds and wider dynamic range. Therefore, the developed strategy represents a promising way to convert standard colorimetric bioassays into optical biosensors with improved sensitivity. [Copyright &y& Elsevier]

Abstract: Optical and spectroscopic properties of Er3+–Yb3+ co-doped TeO2–WO3–Nb2O5–Na2O–Al2O3 glasses and fibers were investigated. Emission spectra and fluorescence lifetimes of 4I13/2 level of Er3+ion as a function of rare earth concentration and fiber length were measured in glasses. Results show that the self-absorption effect broadens the spectral bandwidth of 4I13/2→4I15/2 transition and lengthens the lifetime significantly from 3.5 to 4.6ms. Fibers were fabricated by the rod-in-tube technique using a Heathway drawing tower. The emission power of these Er3+–Yb3+ co-doped Step Index Tellurite Fibers (SITFs; lengths varying from 2 to 60cm) were generated by a 980nm diode laser pump and then the emission power spectra were acquired with an OSA. The maximum emission power spectra, within the 1530–1560nm region, were observed for fiber lengths ranging from 3 to 6cm. The highest bandwidth obtained was 108nm for 8cm fiber length around 1.53µm. [Copyright &y& Elsevier]

Lightweight materials and structures have attracted tremendous interests for their compelling advantages in a range of engineering problems that have placed heightened requirements in safety, environment, competitiveness and cost over recent years. As an effective approach, hybrid systems aim to take advantages and characteristics of different materials to maximize their functional roles in lightweight structures, thereby enhancing their respective material efficiency. This article provides a critical review on the advances in hybrid materials and structures for crashworthiness and energy absorption performance, in which fiber reinforced plastic (FRP), metals, cellular fillers and their hybrid configuration are discussed respectively. Attention is paid to the hybridization of different forms of FRP-FRP, FRP-metal, cellular filling materials with FRP structures, thereby demonstrating their constructive characteristics for different design goals. Crashworthiness and energy absorption performances of various hybridized materials, such as carbon fiber reinforced plastic (CFRP), glass fiber reinforced plastic (GFRP), aluminum/steel, metallic foams/honeycombs/lattices, are evaluated and compared in detail. After highlighting the knowledge gaps in existing literatures, this review provides an outlook on the possible future research. It is expected to gain new insights into the design of novel lightweight hybrid configurations for aerospace, automotive, nautical and railway applications. • Constituent materials and preparation technology of hybrid energy absorption structures. • Experimental characterization and modeling of hybrid energy absorption structures. • Failure mechanism and parameter analysis of hybrid energy absorption structures. • Current challenges and future developments of hybrid energy absorption structures. [ABSTRACT FROM AUTHOR]

• Fracture process changes from brittle to ductile as the temperature increased. • Interfacial strength decreases with increasing temperature and water immersion time. • Interfacial strength restores after drying. • Temperature dependence could be estimated via DMA and/or microindentation. • Water absorption dependence could be determined using the mass uptake behavior. The effects of temperature and water absorption on the mechanical properties at the interface of a two-phase hybrid carbon/glass fiber reinforced thermoplastic epoxy composite rods were investigated. The push-out tests were performed on three types of these hybrid composite rods, with different carbon/glass ratios, at various temperatures and water immersion times to investigate their interfacial shear strength and fracture mechanism. Debonding occurred at the interface between glass fiber bundles and thermoplastic epoxy, followed by sinusoidal behavior during sliding, as revealed by the load–displacement curve. The interfacial debonding and sliding strengths decreased with increasing the temperature. The interfacial strengths also decreased with increasing water immersion time, but they were both restored after drying, for all the samples tested. In addition, the effects of temperature and water absorption on the thermoplastic epoxy matrix were also evaluated and the interfacial shear properties of hybrid composite rods were estimated. [ABSTRACT FROM AUTHOR]