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A review of literature about industrially important composite skew plates, which are used as roofing and flooring units to cover non-rectangular parallelogram shaped plan areas, shows that the aspect of progressive failure has not received any attention from researchers which is essential to comprehensively understand failure behaviour from initiation to the ultimate stage. In the present approach stiffness degradation of a damaged plate is considered only at the point of damage in the corresponding lamina at all stages of first and progressive failure and the present outputs match excellently with published experimental results. This realistic modelling of failure behaviour is the novelty of this paper. Apart from reporting the failure load values, the failure zones and nature of damage progress on the skew plate surfaces are also presented which are expected to be valuable inputs for non-destructive health monitoring. [ABSTRACT FROM AUTHOR]

In this article, wave propagation in a one-dimensional (1-D) composite periodic frame structure is analyzed using spectral finite elements (SFE) method together with Bloch's theorem. Each element in the periodic frame structure is modeled as a first-order shear deformation theory (FSDT) beam element and wave equations for the beam elements are derived using FSDT considering axial, flexural, and shear deformations. Next, these equations are solved using the frequency domain SFE method to obtain an elemental dynamic stiffness matrix which on assembly gives the dynamic stiffness matrix for the unit cell of the periodic structure. A polynomial eigenvalue problem is formulated thereafter using Bloch's theorem to evaluate the dispersion coefficients and wave amplitude ratios. Finally, the entire periodic frame is modeled as homogenized two-noded elements capturing the wave response of the PS with a drastic reduction in computational cost. The results obtained using the present method are validated with finite element simulation using ANSYS mechanical Ansys Parametric Design Language (APDL). The frequency band gaps observed in the frequency domain responses are investigated and corroborated with those predicted by the dispersion relations. This is followed by a detailed parametric study on the influence of different parameters on the band gap characteristics. The present method provides a scheme of wave propagation analysis of composite periodic frames with substantial computational efficiency. [ABSTRACT FROM AUTHOR]

The microstructures, shape memory properties, and mechanical properties of 3D-printed ZrCu–Ti6Al4V laminated composites were investigated in this study. The microstructure of the laminated composite effectively combines the characteristics of two alloys. The shape memory effect and mechanical properties of the laminated composite are affected by the thickness of the layer. The results reveal that higher austenite transformation temperature than ZrCu with total recovery strain close to ZrCu, and a compression strain exceeding 21% can be achieved by 3D-printed ZrCu–Ti6Al4V laminated composite with thickness of 0.25 mm. Additionally, the composite with thickness of 0.5 mm demonstrates excellent fracture toughness values of 44.30 MPa⋅m1/2, as well as high yield strength and flow stress values reaching 1818 MPa and 2194 MPa respectively at a strain rate of 3500 s-1. This study highlights that incorporating Ti6Al4V layers into ZrCu through 3D-printing can significantly enhance mechanical properties while maintaining favorable shape memory properties, thus combining the advantages of functional and structural materials.

The study aimed to investigate the impact behavior of fabric laminates composed of carbon, Kevlar, and hybrid materials through low‐velocity impact tests. Non‐hybrid and hybrid laminates were created using layup techniques with sandwich stacking sequences. Drop weight impact tests were conducted using varying levels of impact energy to assess the influence of stacking sequence and hybridization on impact properties. The results showed significant improvements in impact properties with increasing stacking sequence, particularly a 108.8% and 137.4% enhancement in C4 and K4 laminates, respectively. Kevlar laminates exhibited higher energy resistance than carbon laminates, and the Kevlar‐carbon‐Kevlar‐carbon hybrid laminate demonstrated superior impact force and energy absorption capabilities. Additionally, the study analyzed penetration depth and identified different failure modes dependent on stacking sequence and impact energy levels. These findings provide valuable insights for optimizing fabric laminated composites. Thus, the research could be implemented in industries requiring materials with enhanced impact resistance, such as aerospace, automotive, sports equipment, and protective gear manufacturing. Highlights: Investigated the impact performance of stacked fabric structures, including carbon, Kevlar, and hybrid laminated composites, through low‐velocity impact tests.Fabricated both non‐hybrid and hybrid laminates using layup techniques with a sandwich stacking sequence to assess the impact properties of the composite laminates.Observed greater penetration depth in the C2 stacked structure, while the KCKC hybrid laminate showcased greater resistance to a depth of penetration (DOP).Various failure modes were investigated, demonstrating their relationship with stacking sequence and impact energy levels. [ABSTRACT FROM AUTHOR]

The present study deals with shear wave propagation in a fully coupled Magneto-Electro-Elastic (MEE) multi-laminated periodic structure having non-uniform and imperfect interfaces. As a solution methodology, we applied a more general low-frequency dynamic asymptotic homogenization technique where the solution will be single-frequency dependent and the obtained results generalize those published in Chaki and Bravo-Castillero (Compos Struct 322:117410, 2023b) where the perfect contact case was studied. Effective homogenized dispersive equations of motion in second- and fourth-order approximations, also known as "Good" Boussinesq equations in elastic case, are derived. Local problems, closed-form expression of dispersion equations in second and fourth-order approximations and closed-form solutions of first and second local problems in second-order approximation for tri-laminated MEE periodic structure have been obtained and also validated for elastic laminates with imperfect contact case and MEE laminates with perfect contact case. The effect of non-uniform and imperfect contact, angle of incidence, unit cell size, volume fraction and ME-coupling on the wave propagation is illustrated through dispersion graphs. The effect of non-uniform and imperfect contact on dispersion curve serves as the highlight of the present work. [ABSTRACT FROM AUTHOR]

The main purpose of this research is to observe the effect of alkalisation of rattan, bamboo fibre, and eggshell particles addition in the fabrication of hybrid polyester laminated composite. A 5% NaOH treatment of fibres was conducted, and 5% eggshell particles was added to the composite. The FTIR analysis was done to reveal the presence of nanol, and thermal stabilities were evaluated by TGA, DTG and DTA. Furthermore, water absorption and biodegradability of the composite were also investigated. Mechanical properties were tested with compatible ASTM standards. The 5% NaOH treated 30 wt.% fibre- loading enhanced the tensile strength, flexural strength, impact strength, and hardness by 9%, 2%, 7%, and 4%, respectively compared to the raw composites. On the other hand, the addition of 5% eggshell particles decreased the tensile strength, flexural strength, impact strength, and hardness of the raw 30 wt% fibre-reinforced composite by 5%, 4%, 3%, and 2%, respectively In addition, the raw 30 wt% fibre-reinforced composite has the highest biodegradability, and water absorption percentage than the alkali-treated and eggshell added fibre-reinforced composite. The raw 30 wt% fibre-reinforced composite has dictated over the alkali-treated and eggshell added fibre-reinforced composite in terms of thermal stability. [ABSTRACT FROM AUTHOR]

This paper reports a detailed numerical investigation on the buckling aspects of laminated composite shell panels of three forms (cylindrical, spherical and hyperbolic paraboloid) with five support conditions exposed to linearly varying in-plane edge load employing eight nodded isoparametric finite element formulation. The impacts of different parameters including ply orientation, load factor, shell forms, aspect ratio, modulus ratio, curvature ratio, width-to-thickness ratio and angle of lamination on the buckling load of shell panels are examined. It is found that the various parameters addressed in this study have a remarkable impact on the buckling phenomena of laminated composite shell panels. Further, a comparison is made showing the effects of five types of compressive edge loads like uniform, triangular, parabolic, partial edge load and point load on the buckling phenomena of laminated shell panels with respect to five support conditions. [ABSTRACT FROM AUTHOR]

AbstractThe present study investigates free vibration analysis of cylindrical panels made of porous orthotropic layers. Porous material properties are modeled using uniform and two non-uniform porosity distribution patterns through the thickness. The theoretical formulations are expressed based on the higher-order shear deformation theory. The equations of motion of laminated cylindrical panels are established by performing Hamilton’s principle. These fundamental partial differential equations are solved analytically for the laminated cylindrical panels, which are simply supported on all edges. Galerkin’s solution procedure is applied to obtain the natural frequency equation. The natural frequencies are compared to results in the literature to verify the obtained frequency equation. Afterward, novel parametric studies are developed to discuss the influence of porosity parameters, porosity distribution patterns, geometrical parameters, orthotropy, and lamination sequences on the free vibration response of porous laminated cylindrical panels. [ABSTRACT FROM AUTHOR]

In this study, the mechanical performances of glass fiber-reinforced notched and pin-connected composite plates were investigated experimentally and numerically. For this purpose, composite plates with a circular hole, semicircular double-edge notched, U-edge notched, and single and double pin joints were prepared from [ 0 ° ] 8 layer glass fiber composites. Tensile tests were carried out on the obtained specimens. The effect of notch type, number of pins, and position of pins on plate damage load and type was investigated for linear and non-linear material behavior. Progressive failure analysis was performed using the Hashin damage criteria. Subprogram codes were written in the Ansys program using the finite element method. According to the obtained data, it was determined that the type of notch and the number of pins have a significant effect on the damage loads of the plates and the behavior of the material is important in terms of convergence to the experimental results in numerical solutions. In single-pin composites, the type of damage changed from net-tension to shear out as the pin approached the free edge of the plate. It was observed that the distance between the pins did not have any effect on the damage type of the composites in the double-pin joint structure. Compared to single-pin joint composites, double-pin joint composites were found to carry a maximum of 34% more damage load. The convergence rate of experimental and numerical data was obtained as a minimum of 92.1% for nonlinear material behavior and a minimum of 73.4% for linear material behavior [ABSTRACT FROM AUTHOR]

This study investigates the vibration transmission in coupled metal and composite plates with curvilinear fibers from the power flow viewpoint. The time-averaged power flow variables are obtained using a substructure method to assess the levels of vibration transmission of coupled structures with various configurations and fiber angles. It is demonstrated that by adopting tailored curvilinear fiber designs, the vibration transmission through the coupling edge of the plates can be effectively suppressed. Variable fiber angle designs are shown to exert significant effects on the dominant-excited mode and can be exploited to achieve desirable energy transmission paths for low-vibration transmission and effective suppression. [ABSTRACT FROM AUTHOR]

Carbon fabric/resin laminated composites (CFRC) are extensively used in aerospace, transportation, and other fields owing to their superiorities of lightweight, high strength, and convenient integral molding. Therefore, strong interlaminar binding and prominent wear resistance are urgent requirements for avoiding premature failure of laminated materials in harsh working environments. To elevate the superficial wear resistance and interlaminar bonding strength of composites simultaneously, the modified composites were obtained by introducing carbon fiber powder (CFP) with different densities on the surface of the composites and between layers. The experimental results indicate that CFP can be evenly distributed in the interlaminar resin enrichment zone of the sample (CFRC‐40) when the deposition density is 40 g/m2. Consequently, CFRC‐40 presents optimal thermal conductivity owing to better heat transfer bridges between layers of the composite established by CFP. At the same time, the mechanical properties such as the tensile, impact, and interlaminar shear strengths of CFRC‐40 are improved by 42.8%, 10.2%, and 8.5%, respectively, compared with the original CFRC, which are attributed to the absorption of crack propagation energy and the inhibition of crack propagation by CFP. Furthermore, the dynamic friction coefficient maintains at a high level after introducing CFP with a density of 40 g/m2, while the wear rate significantly decreases by 61.2% from 12.99 × 10−14 m3(N m)−1 to 5.04 × 10−14 m3(N m)−1. This study proposes an innovative strategy to improve the interlaminar bonding of carbon fabric/resin laminated composite, which is conducive to obtaining composite with excellent mechanical and tribological properties. Highlights: A facile and effectual method was adopted to introduce carbon fiber powder (CFP) into the interlamination and surface of the composites simultaneously.The mechanical properties and abrasive resistance of the composites were obviously strengthened by regulating the content and distribution of CFP.CFP at a certain scale, could not only hinder the propagation of cracks but also alleviate the surface wear and extend the service life of composites. [ABSTRACT FROM AUTHOR]

Fabric-layered composites play a crucial role in safety and surveillance applications, making it imperative to accurately predict their impact behavior. This research focuses on creating a machine-learning model to predict the impact behavior of fabric-stacked composites, specifically carbon and Kevlar fabrics. Low-velocity impact tests were performed with varying parameters, and the impact energy and laminate thickness information were used to train machine-learning models to predict impact properties such as impact force, displacement, and absorbed energy. It was observed that the impact force increased by 118.5 % in carbon-laminated fibers and 175.8 % in Kevlar-laminated fibers, while the hybrid layer showed a 101.4 % increase upon impact from 16J. Displacement can affect the stability of the layered structure; thus, a similar stacking sequence is less stable than the hybrid laminated structure. In terms of absorbed energy, as the laminated layers increase, carbon fiber laminate absorbs 4.8 times more energy, and Kevlar fiber and hybrid laminated structures absorb 3 times more energy at higher impact energy. Furthermore, four machine learning models were used to investigate the impact behavior of identical and mixed-layered laminated composites. The impact force and displacement were predicted with higher accuracy using the polynomial regression model, achieving 80 % and 89 % accuracy, respectively. The support vector machine predicted the absorbed energy with approximately 96 % accuracy. In continuing, the experimental results closely matched the predictions made by the other machine learning models utilized in this study. Additionally, the importance of distinctive features and their influence on the performance of the machine learning-based model were interpreted using transposed features of importance and dependency plots. Various failure modes in fabric laminated composites were also identified, providing insights to enhance the performance of stacked fiber materials.

The bending analysis of isotropic, laminated composite and cylindrical sandwich shells was carried out using a higher order shear deformation theory which incorporates undetermined integral in the displacement field. The model proposed involves only four variables. Moreover, unlike the conventional FSDTs, the shear correction factor is not necessary. The Hamilton's principle and the Navier's method are employed to determine and solve the equations of motion. The present analytical model was compared with other higher-order theories in the literature. In addition, finite element analysis methods were designed to calculate displacements and stresses of shells. Shells are subjected to uniform loads. Results are given for shallow and deep shells and thick to thin. According to the analysis, kinematics, based on the indeterminate integral component, are very effective and enable researchers to investigate laminated plates and shells more accurately than traditional models. [ABSTRACT FROM AUTHOR]

In this study, the failure behavior of carbon fiber‐reinforced pin‐jointed composite plates were analyzed for different criteria. For this purpose, composite plates with a single and double pin joints were prepared from four layers carbon fiber composites. The effect of pin number, pin position on plate damage load and type was investigated experimentally and numerically under the tensile test. Numerically, progressive damage analysis was performed using Hashin and Puck failure criteria, and the approach rates to the experimental results were determined. It was observed that the experimental results obtained for single pin joint composites and the numerical data obtained using the Puck damage criterion were at least 87 % compatible, and this rate was determined as 85 % for the Hashin failure criterion. For the double pin jointed composites, it was seen that the experimental results and the results of the Puck damage criterion were compatible with at least 90 %, and this rate was obtained as 84 % for the Hashin failure criterion. The dominant damage type seen in the specimen is matrix shear and fiber compression according to the Hashin damage criterion, inter fiber failure in transverse tension for Puck. [ABSTRACT FROM AUTHOR]

The primary objective of this research was to observe the physical, mechanical and thermal properties of rattan fiber reinforced hybrid epoxy resin laminated composites. The hybrid composites were fabricated utilizing rattan fiber, carbon fiber, jute fiber and epoxy resin as matrix materials. This study employed two types of rattan fibers, namely plain weave and twill weave. These rattan fibers were combined with carbon fibers and jute fibers separately, forming R3C2, R′3C2, R3J2 and R′3J2 composites. The fabrication process involved conventional hand lay-up followed by high-temperature treatment and pressure application under a hydraulic press to ensure effective curing and minimize voids within the final composites. These were compared with the properties of monolithic laminates. Mechanical properties, including tensile, flexural and hardness characteristics, were assessed to evaluate the impact of rattan fibers in hybrid composites. Failure modes of the fractured tensile specimen were examined using Scanning Electron Microscopy (SEM). Additionally, water absorption behavior and fire retardant painting test were conducted. The results showed that hybrid composites reinforced with plain weave rattan fiber (R3C2 & R3J2) exhibit superior tensile strength, flexural strength and hardness. In comparison to R5 composites, the tensile strengths of these samples have improved by 104.36% and 349.68%, respectively. Moreover, the flexural strengths of R3C2 and R3J2 composites exhibit significant enhancements of 218.41% and 90.9%. These composites also excel in the Shore D Hardness test. Hence, it can be concluded that the hybrid composites reinforced with rattan fibers demonstrate enhanced physical, mechanical, and thermal properties.

This paper uses isogeometric analysis (IGA) based on higher-order shear deformation theory (HSDT) to study the dynamic response of bio-inspired helicoid laminated composite (B-iHLC) plates resting on Pasternak foundation (PF) excited by explosive loading. IGA takes advantage of non-uniform rational B-spline (NURBS) basic functions to exactly represent the structure geometry models and the attainment of higher-order approximation conditions. This method also ensures a C1 continuous function in the analysis of transverse shear deformation via HSDT. Furthermore, IGA eliminates the requirement for correction factors and delivers accurate results. Pasternak foundation with two stiffness parameters: springer stiffness (k1) and shear stiffness (k2). The derivation of the governing equations is based on Hamilton's principle. The proposed method is validated through numerical examples. A comprehensive analysis of the impact of geometrical parameters, material properties, boundary conditions (BCs), and foundation stiffness on dynamic response of B-iHLC plates is carried out.

Thermo-mechanical buckling analysis of laminated spherical shells bounded with the piezoelectric actuator layers has been presented in this article. Applied loads are a combination of thermal, mechanical and electrical loads. Derivations of equilibrium and stability equations are based on the classical laminated shell theory and Sanders's nonlinear kinematic relations. The analysis employs the Galerkin method to achieve closed-form formulas for the buckling loads of the piezo-laminated spherical shell. Effects of applied actuator voltage, voltage sign, geometrical parameters of the shell (length, diameter, and thickness), material properties, and layout of composite layers on the buckling strength are investigated. Analytical solutions are obtained for three types of thermal loading, and one thermo-mechanical loading condition. The results are validated by the known data in the literature. [ABSTRACT FROM AUTHOR]

This study investigates the temperature-dependent quasi-static magnetoelectric (ME) response (αE) of electrically poled lead-free Na0.4K0.1Bi0.5TiO3–NiFe2O4 (NKBT–NFO)-laminated composites. The aim is to understand the temperature stability of ME-based sensors and devices. The relaxor ferroelectric nature of NKBT is confirmed through impedance and polarization–electric (PE) hysteresis loop studies, with a depolarization temperature (Td) of approximately 110 °C. Heating causes a decrease and disappearance of planar electromechanical coupling (Kp), charge coefficient (d31), and remnant polarization (Pr) above Td. The temperature rise to 125 °C also leads to a reduction in magnetostriction (λ) and magnetostriction coefficient (q = dλ/dH) of NFO by approximately 33% and 25%, respectively. At room temperature, the bilayer and trilayer configurations exhibit maximum ME responses of approximately 33 mV/cm·Oe and 80 mV/cm·Oe, respectively, under low magnetic field conditions (H ∼ 300–450 Oe). The ME response of NKBT/NFO is highly sensitive to temperature, decreasing with heating in accordance with the individual temperature-dependent properties of NKBT and NFO. This study demonstrates a temperature window for the effective utilization of NKBT/NFO-based laminated composite ME devices. [ABSTRACT FROM AUTHOR]

Composite driveshafts have emerged as a potent substitute for traditional driveshafts because of their excellent strength-to-weight and stiffness-to-weight ratios. At the same time, usage of multi-walled carbon nanotubes (MWCNTs) as a reinforcement has gained a great momentum due to their superb mechanical, electrical, and thermal characteristics. In this work, a micromechanical model combining the rule of mixtures and the Halpin-Tsai (H-T) model was used to calculate elastic constants of MWCNTs-added carbon fiber reinforced epoxy resin. This micromechanical model considers the effect of agglomeration, aspect ratio, waviness, and random orientation of MWCNTs. Elastic constants of MWCNTs/epoxy resin calculated by using micromechanical model was compared by experimental results available in the literature. Moreover, finite element analysis (FEA) was carried out to predict the critical torsional buckling load of composite driveshafts for various MWCNTs concentrations and fiber orientation angles. The FEA results were compared with the results obtained theoretically. The results showed that Young's modulus of MWCNTs/epoxy resin calculated by using the micromechanical model follows the experimental findings. When compared to pure carbon fiber-reinforced epoxy resin, E1, E2, E12, and G23 (elastic constants of composite lamina) showed improvements of 0.66%, 27.80%, 49.02%, and 37.50%, respectively, in the case of 10vol.% MWCNTs addition. The ply orientation angle has a more dominant effect on Tcr than the Doi: 10.24012/dumf.1336638 MWCNTs concentration. [ABSTRACT FROM AUTHOR]

As laminated composites are applied more commonly, Prognostics and Health Management (PHM) techniques for the maintenance of composite systems are also attracting attention. However, applying PHM techniques to a composite system is challenging due to the data imbalance problem from the lack of failure data and unpredictable failure cases. Despite numerous studies conducted to address this limitation, including techniques like data augmentation and transfer learning, significant challenges remain. In this study, the Wasserstein Generative Adversarial Network (WGAN) model using a time-series data augmentation technique is proposed as a solution to the data imbalance problem. To ensure the performance of the WGAN model, time-series data augmentation of experimental data is executed with a frequency analysis. After that, a One-Dimensional Convolutional Neural Network (1D CNN) is used for fault diagnosis in laminated composites, validating the performance improvement after data augmentation. The proposed data augmentation significantly elevated the performance of the 1D CNN classification model compared to its non-augmented counterpart. Specifically, the accuracy increased from 89.20% to 91.96%. The precision improved remarkably from 29.76% to 74.10%, and its sensitivity rose from 33.33% to 94.39%. Collectively, these enhancements highlight the vital role of data augmentation in improving fault diagnosis performance. [ABSTRACT FROM AUTHOR]

Recently, the demand for lightweight multilayered parts in electronics and biomedical fields has been accelerated and shown great interest in understanding the combined effect of multilayered materials. However, these industries are still facing the challenge of developing dissimilar multilayered materials that can be suitable for biomedical applications. In this context, magnesium emerges as a promising biocompatible material used for several biomedical applications. However, the issues related to joining magnesium alloys with other similar materials still need to be solved. Moreover, friction stir additive manufacturing (FSAM) occupies a niche domain for developing or joining biocompatible materials such as magnesium alloys with low weight and high strength. Therefore, the present work highlights the development of a multipurpose three-layered multifunctional laminated composite plate of magnesium-based AZ31B–Zn–Al 1100 through the FSAM route. Microstructural and morphological examinations were carried out by light microscopy and FESEM equipped with EDS analysis and line mapping. Moreover, the grain refinement at the interfaces during the FSAM was also addressed using the electron backscattered diffraction (EBSD) study. Further, investigation on mechanical properties such as tensile test with fractography analysis and microhardness variation at the cross-section of the built-up section has been investigated. Furthermore, the corrosion and tribological analysis was also performed, and a 3D profilometer was used to visualize the corroded and worn-out surfaces. The microstructural results revealed that the average grain size of 6.29 μm at interface AZ31B–Zn and 1.21 μm at interface Zn–Al 1100 occurred, improving the bonding strength and overall properties. The tensile strength has occurred as 171.5 MPa at 15.5% elongation, whereas maximum microhardness is reported as 105 HV at the interface of AZ31B–Zn and 84.6 HV at the interface of Zn–Al 1100. The corrosion rate was calculated as 0.00244 mm/day, and the average coefficients of friction (COF) for both the interfaces, such as AZ31B–Zn and Zn–Al 1100, are 0.309 and 0.212, respectively. [ABSTRACT FROM AUTHOR]

Copyright of Advanced Textile Technology is the property of Zhejiang Sci-Tech University Magazines and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The paper considers the issues of interaction of the molten metal at the interface of explosively welded NiCr/titanium alloy laminated composites with the reaction zone formed during heat treatment, as well as the features of its destruction after welding. It was established that the molten metal is a heterogeneous mixture based on Ni(Cr,Ti) and Ti(Ni,Al) solid solutions and NiTi and Ni3Ti intermetallic compounds. The estimated existence time of molten metal areas in the liquid state was ~10−8–10−11 s. The obtained values are comparable with the time of the unloading wave arrival at the contact surface, which is the reason for the presence of fracture areas in the form of detachments on the fracture surface. Continuous nanometer-size interlayers with an amorphous structure, due to the ultra-high cooling rate of the liquid melt, induce viscous destruction of the interface. Heat treatment at temperatures of 700 and 850 °C led to the formation of a layered reaction zone at the NiCr/Ti boundary, consisting of interlayers of solid solutions based on Ti2Ni, TiNi, and TiNi3 intermetallic compounds, as well as inclusions of a Cr(Ti) solid solution. The diffusion flow gradient was predominantly directed into the titanium alloy. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, carbon fiber-reinforced U-notched composite plates were repaired with composite patches made of the same material using adhesive bonding and their mechanical performance was investigated experimentally and numerically. Repairs were made by applying a double-sided composite patch to the notched thin composite plates. The repaired composite plates were tested under tensile load. The effect of the variation in notch width and depth on the repaired plate failure load and type was investigated. At the end of the experiments, load–displacement graphs of each specimen were obtained. The effect of variation in notch depth and width in the repaired specimens was not as dominant as in the non-repaired specimens. While the variation in notch dimensions changed the failure load between 34% and 37% in the non-repaired specimens, this rate was between 18% and 21% in the repaired specimens. In the numerical analysis, progressive failure analysis was performed using the Hashin Failure Criteria. Subroutine codes were written in the program Ansys, which uses the finite element method for numerical analysis. In the results, numerical and experimental load–displacement graphs and failure types of the specimens are presented comparatively. The convergence rate of the experimental and numerical data was between 92% and 99.8%. [ABSTRACT FROM AUTHOR]

Explosive welding is widely used in the manufacture of dissimilar metal composite plates. In this work, TC4/TA1/Ti6321 titanium alloy laminated composites were successfully prepared by explosive welding. The interfacial characteristics of the laminated composites were studied by energy dispersive spectroscopy (EDS), electron backscattered diffraction (EBSD), transmission electron microscope (TEM), and other characterization methods. The dynamic mechanical properties of the laminated composites were investigated by using the split Hopkinson pressure bar (SHPB). The results show that the interface of laminated composites was well bonded. There was a high density of crystal defects including dislocations and twins near the interface. The composite plates showed a hard/soft/hard hardness distribution as a whole, and the microhardness increased near the interface. Due to the existence of the interface, the dynamic mechanical properties of laminated composites show different results. The dynamic compressive stress-strain curve of laminated composites showed an equilibrium type, and the strain strengthening effect was lower than that of homogeneous materials. The failure mode of laminated composites was adiabatic shear failure mode.

These articles presents an experimental investigation on mechanical, vibration, and wear behavior of (aloevera/flax/hemp/wire mesh/BaSO4) laminated composite. The mechanical characterization was performed with ASTM standard specimens. The free vibration performance was analyzed under two clamping conditions and boundary conditions (clamp-clamp & clamp-free). The wear test trails were accomplished using a pin on disc at different process parameters like sliding speed (3–5 m/s), sliding distance (1000 m) and applied load (10–30 N) under sliding dry environment at room temperature of 28 ± 5◦C. The scanning electron microscopy was used to examine the interaction between the matrix and reinforcement interface after the failure. The experimental results revealed that the addition of wire mesh and BaSO4 filler in the fabricated composite Aleovera+Hemp+Wiremesh+Flax+Aleovera+BaSO4 composite (C4) increased the tensile strength by 8.68% compared to Aleovera+Hemp+Wire mesh+Flax+ Aleovera (C3) composite and it also depicts that the addition of wire mesh and BaSO4 as reinforcement has improved 5.42% of flexural strength compare to Aleovera+Hemp+Flax+Aleovera+BaSO4 composite (C2). The addition of BaSO4 improved the hardness in both C2 and C4 composites. The 5% addition of BaSO4 enhanced the natural frequency of the composites. Among the composites, the C4 has shown the highest coefficient of friction during the experimental trials.

Laminated Mg-intermetallic composites were successfully fabricated by reaction synthesis in vacuum using 1 mm thick magnesium sheets and 0.25 mm thick copper foils. The final microstructure consisted of alternating layers of a hypoeutectic alloy containing crystals of CuMg2 and eutectic mixture of CuMg2 and solid solution of copper in magnesium and unreacted magnesium. The mechanical properties and fracture behavior of the fabricated composites were examined under different loading directions through compression, three-point bending and impact tests. The results indicated that the composites exhibited anisotropic features. The specimens compressed in the parallel direction failed by cracking along the layers of intermetallics and buckling of magnesium layers. The specimens compressed in the perpendicular direction failed by transverse cracking in the intermetallic layers and fallowing catastrophic cracking inclined about 45° to the interface of both intermetallic and magnesium layers. The flexural strength of the composites was higher in perpendicular than in parallel direction. When the load parallel to the layers was applied, the failure occurred by cleavage mode showing limited plastic deformation. When the load perpendicular to the layers was applied, the failure occurred by transverse cracking of the intermetallic layers and gradual cracking of the Mg layers. The Charpy-tested samples showed the same fracture behavior as the bend-tested specimens, which indicated that the same mechanisms operated at both high impact rate and low bending-test rate.