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This paper elaborates on the wave propagation characteristics of a smart sandwich plate consisting of smart piezo composite layers on a plate's upper and lower borders via an auxetic core. This study's equation of motion was derived using a refined version of the Shear-deformation theory at a higher order, or HSDT. Additionally, detecting the properties of the auxetic core and piezoelectric composite layers employs a micromechanical model. The fundamental equations of the smart sandwich plates were formulated utilizing the Hamiltonian principle and Maxwell's law. Then, the governing equations of a sandwich plate are solved using an exponential form and an analytical method. Furthermore, the phase velocity of the intelligent sandwich plate is provided based on the layer thicknesses of the auxetic core and thicknesses of intelligent piezoelectric composite layers. In addition, each figure calculates and presents the weight of the Winkler–Pasternak coefficient, the viscoelastic substances factor, the source of the outside electricity, and the volume percent of reinforcement in the matrix on the phase velocity. [ABSTRACT FROM AUTHOR]

This paper presents the time-domain viscoelastic formulation based on the Carrera unified formulation (CUF) to obtain the response of composite structures submitted to bending loads. The governing equations are obtained through a modified form of the principle of virtual displacement (PVD) for a viscoelastic analysis. The problem is solved using the Laplace transform instead of direct integration to reduce the computational cost. The results demonstrate the strong capability of the time-domain viscoelastic formulation. Overall, the proposed methodology allows the direct implementation of new optimized high order deformation theories including the thickness stretching effect that may be implemented in futures works. [ABSTRACT FROM AUTHOR]

In order to identify the location and magnitude of the impact force accurately, determine the damage range of the structure and accelerate the health monitoring of key components of the composite, this paper studies the location and magnitude of the impact force of composite plates by an inverse method. Firstly, a PZT sensor mounted on the material plate is used to collect the response signal generated by the impact force, which is from several impact locations, and establish transfer functions between the impact location and the PZT sensor. Secondly, this paper applies several forces to any location on the material plate, and collects the corresponding response signals, and reconstructs the impact force of several locations in turn. Finally, according to the reconstruction result of each location, the correct impact location is identified. Then, an improved regularization method is used to optimize the reconstructed impact force and accurate the magnitude of the impact force. The comparison experiments prove that the recognition error of this method is smaller. [ABSTRACT FROM AUTHOR]

Purpose: When a thick structure is, on the contrary, subjected to moisture absorption, a fairly long time may be needed to reach full saturation. It is, therefore, important to understand and predict the areas of complex composite structures that are more prone to saturation. The material knock-down factors (proportional to the moisture content) may be applied only to these zones, in order to obtain a less pessimistic structural response prediction. The purpose of this paper is to investigate an FE diffusion model that was used to validate the absorption testing results of thick carbon epoxy laminates. Design/methodology/approach: The experimental results were validated by using a diffusion model in Abaqus FE code. Findings: The absorption results of three 15 mm thick carbon epoxy laminates are presented and reproduced via a mass diffusion model. The laminates were conditioned at 70°C and 85 per cent relative humidity in a moisture chamber. Areas more prone to saturation have been predicted by the FE model and the moisture content in the non-saturated areas has been calculated. Practical implications: The practical implications of the absorption model are discussed on an example of an aero-engine fan blade-like structure. Originality/value: Validation of thick panels' absorption data is an important point of novelty of this paper, given the lack of experimental and modelling validation in the open literature. [ABSTRACT FROM AUTHOR]

The flow head of an orifice-type capacitive flow sensor for a conducting liquid consists of a vertically mounted metallic orifice plate in a horizontal pipeline made of insulating material and a rigidly grounded metallic ring or sensing ring placed surrounding the pipeline at a small distance from the orifice plate where the capacitance between the orifice plate and the sensing ring follows a linear relationship with flow rate as reported in the literature. In this paper, a further study on the effect of position of the sensing ring on the sensor capacitance has been carried out along with the modification of the simple parallel plate capacitance principle described in the earlier work by the real disk-type capacitance principle. From this paper, it has been observed that for any position of the sensing ring near the orifice plate, the sensor capacitance decreases linearly with the increase of flow rate and follows the modified capacitance principle similarly as that observed in earlier work. It has also been observed that the sensing ring distance-sensor capacitance product increases almost linearly with the increase of sensing ring distance. From the experimental study of the proposed orifice type capacitive flow sensors installed on two different pipelines, the said modified theory of the sensor appears to be verified in the present paper where the experimental results are reported. [ABSTRACT FROM AUTHOR]

This paper covers the modeling and testing of a helicopter tailboom integrated with a fluidic flexible matrix composite (F²MC) damped vibration absorber. In an advance over previous work, the F2MC absorber presented in this paper treats a combination of tailboom lateral, torsional, and vertical vibrations. A finite element structural model of a laboratory-scale tailboom is combined with a model of attached F2MC tubes and a tuned fluidic circuit. Vibration reductions of over 75% in a coupled 26.8-Hz lateral bending/torsion tailboom mode are predicted by the model and measured experimentally. These results demonstrate that F2MC vibration control is viable at higher frequencies and for more complex vibration modes than previous research had explored. A new absorber with a fluidic circuit that targets two tailboom vibration modes is designed and experimentally tested. On the lab-scale tailboom testbed, the absorber with this circuit is shown to provide vibration reductions of over 60% in both a 12.2-Hz vertical mode and a 26.8-Hz lateral bending/torsion mode. Using this new absorber, vertical and lateral/torsion mode damping are achieved with almost no added weight relative to a purely vertical absorber. [ABSTRACT FROM AUTHOR]

In recent years, many scholars have conducted in-depth and extensive research on the mechanical properties, preparation methods, and structural optimization of grid structural materials. In this paper, the structural characteristics of composite intelligent grid are studied by combining theoretical analysis with experiments. According to the existing conditions in the laboratory, the equilateral triangular grid structure experimental pieces were prepared. In this paper, principal component analysis combined with nearest neighbor method was used to detect the damage of composite plates. On this basis, the multiobjective robustness optimization of the structure is carried out based on artificial intelligence algorithm, which makes the structure quality and its sensitivity to uncertain parameters lower. Particle swarm optimization (PSO) is used in neural network training. The damage characteristics of different grid structures, different impact positions, and different impact energies were studied. The results show that the structural damage types, areas, and propagation characteristics are very different when the structure is impacted at different positions, which verifies that the grid structure has a good ability to limit the damage diffusion and shows that the grid structure has a good ability to resist damage. [ABSTRACT FROM AUTHOR]

AbstractThis paper presents an analytical model for the free vibration of composite laminated plates with arbitrary biaxial symmetric geometry under elastic boundary conditions, applicable to cross-ply fiber-reinforced composites. In this model, the domain segmentation integral method proposed by the authors is extended to the first-order shear deformation theory (FSDT) and the laminated plate theory. The energy integrals pertaining to the FSDT are analytically simplified by segmenting the integration domains and synthesizing orthogonal polynomial displacement functions over the plate domain coordinate intervals. This synthesis is achieved through the amalgamation of the penalty function method and the Gram-Schmidt orthogonalization process. Then, using the Rayleigh-Ritz procedure, a series solution for the free vibration problem of cross-ply fiber-reinforced composite laminated plates is obtained. The model provides an analytical mathematical relationship between the profile curve of composite laminated plates with arbitrary biaxial symmetric geometry and the strain energy, kinetic energy, and boundary potential energy during vibrational processes. The correctness and applicability of the method are validated by comparing the obtained results with those from the literatures. New results for laminated plates, such as hexagonal and astroid-shaped plates, were presented as references for future research. Taking a track shaped plate as an example, the effect of the number of layers on the vibration characteristics of cross-ply fiber-reinforced composite laminated plates with a certain thickness is studied. [ABSTRACT FROM AUTHOR]

As one of the high-strength structures of the aerospace composite panels, the bonding of the stiffened skins affects the mechanical properties of the overall structure. A nonlinear detection method based on subharmonic modulation is proposed in order to detect the debonding damage of composite stiffened structures in the present paper. The debonding damage interface is simplified to a two-degree-of-freedom nonlinear model using interface contact theory. The multi-scale method is employed to analyse the generation mechanism of subharmonic modulation. The experiment is performed on the composite stiffened plate. Then based on the frequency response function characteristics of in-situ piezoelectric actuator/sensor, both high- and low-frequency excitation signals are applied to the composite stiffened plate, and the debonding damage of stiffeners is identified by the subharmonic modulation component in the response signal spectrum. It is shown, both theoretically and experimentally, that the subharmonic modulation method can effectively detect the interfacial debonding damage of composite stiffened structures and is insusceptible to the interference of environmental noise and the inherent nonlinearity of materials. [ABSTRACT FROM AUTHOR]

This paper presents a novel approach using Generative Adversarial Networks (GANs) to predict thermal stress distribution in binary composites. The composite plates, generated randomly, serve as the basis for finite element simulations that produce datasets for training the GANs. To enhance the training process, binary images representing composite architecture are combined with corresponding thermal stress distribution images, creating a unified dataset. Remarkably, the trained GANs exhibit a high level of accuracy in predicting thermal stress within the composites. The results underscore the potential of GANs in accurately predicting thermal stress, opening avenues for advancements in materials science. [ABSTRACT FROM AUTHOR]

In this paper a quasi-three-dimensional (3D) refined using a novel higherorder shear deformation theory is developed to examine the static bending with two different type porosity distribution of porous for advanced composite plates such as functionally graded plates. In this present theory, the number of unknowns and governing equations is reduced, takes into account the thickness stretching effect into transverse displacement, bending and shear, using a new shape function. The used plate theory approach satisfies the zero traction boundary conditions on the surfaces of the plate without using shear correction factor and the transverse shear strain and shear stress have a parabolic distribution across the thickness of the plates. The virtual work principle is used to obtain the equilibrium equations. An analytical approach based on the Navier solution is employed to obtain the solution for static bending of simply supported FGM plates. The proposed theory shows a good agreement for static bending of FGM plates with other literature results has been instituted of advanced composite plates. Numerical results are presented to show the effect of the material distribution, the power-law FG plates, the geometrical parameters and the porosity on the deflections and stresses of FG plates. [ABSTRACT FROM AUTHOR]

AbstractThis paper studies the free vibration and harmonic response of Functionally Graded Graphene/Epoxy composite plates, considering the First Order Shear Deformation Plate Theory. The weight fraction of graphene variation along the thickness direction with graphene homogeneous dispersed in a polymer matrix. The effective Young Modulus of the plate is predicted by a new micro-mechanical model. The model includes the aspect ratio and weight fraction of nanoplatelets embedded into the matrix. The modal and harmonic of Graphene/Epoxy plates are obtained by the Boundary Element Method formulation for composite plates. The Young modulus calculated from the proposed micro-mechanical model highly agrees with those obtained from experimental results reported in the literature. Results demonstrate a high correlation of the micromechanical model with experimental results and other analytical models. Graphene weight fraction and ratio aspect increase the effective Young modulus of the composite. Boundary Element results show high agreement with Finite Element solutions. Numerical results for modal and harmonic analysis show concentrating graphene near the top and bottom surfaces of the plate is the most effective way to reinforce the plate for increased natural frequencies. The results demonstrate the BEM formulation and micromechanical model can be used as reliable engineering tools for the vibrational analysis of functionally grade graphene composite plates. [ABSTRACT FROM AUTHOR]

By using an effective theoretical model, efficiency and accuracy of design for laminated plates can be significantly improved. However, the existing five-variable higher-order models will encounter difficulty to accurately produce interlaminar stresses, which will influence evaluation on interlaminar performance of laminated plates. Thus, this paper attempts to propose an efficient higher-order model with five variables, where the Legendre polynomial is introduced into in-plane displacement field at each layer. By enhancing compatible condition of displacements and equilibrium condition of stresses, the unknowns depending on the layer number have been eliminated. Differing from other existing five-variable higher-order models, the proposed model can describe the zig-zag effect of in-plane displacements, and fulfill continuity of transverse shear stresses at interfaces. The governing equations are further derived through the principle of virtual displacement, and analytical solutions for only simply-supported plates have been presented. To assess the capability of the proposed method, three-dimensional elasticity solutions have been employed for comparison, and other five-variable higher-order models from the literature have been also chosen for assessment. Numerical results show that the proposed model possesses the same computational efficiency as the selected five-variable models, but can predict more accurate results. In addition, the proposed model is employed to analyze bending behaviors of sandwich and composite plates, and accurate results can be also acquired. Therefore, the present model is proposed to design laminated plates. [ABSTRACT FROM AUTHOR]

The paper investigates the normal interaction between the steel striker, carbon fiber and aramid fiber reinforced plastic plates at a speed ranging from 166.6 to 184.2 m/s. A series of physical and numerical experiments with impact load is conducted to design a mathematical model and numerical algorithm for the composite plate. The behavior and fracture of composites are described by the elastic-brittle model accounting for their different compressive and tensile strengths. The numerical simulation utilizes the finite element method in the EFES software developed by the authors. [ABSTRACT FROM AUTHOR]

This paper aims to study the feasibility of implementing a new bio-composite with a sandwich structure made from date palm tree waste. This is done by valuing such waste, often left in palm groves and burned under most circumstances, which can be a vital resource at the lowest cost. This work has developed several sandwich-structured composite plates based on this waste. The skins are composite materials based on an epoxy matrix and palm tree fibers (Epoxy/Rachis fibers); the core was made of raw wood or a composite with petiole wood particles. After three-point mechanical bending tests, macroscopic analysis and SEM micrographs were used to determine what kind of damage the specimen had. Characterization tests on the new bio-composites showed good thermal properties; with a thermal conductivity below 1W/mK is between 0.0148W/mK and 0.0178W/mK. It is also characterized by its low volumetric mass, less than 1.2g/cm³. These properties make it a good thermal insulator, especially in environmentally friendly bio-construction areas making a sandwich-structured composite using palm tree waste is a very effective, environmentally friendly, and economically inexpensive option. [ABSTRACT FROM AUTHOR]

Background: The plate structure is one of the typical components of the mechanical system and its vibration research has attracted full attention. Graphene platelet is a new high-performance nano-reinforced filler and its emergence provides an opportunity to improve the vibration properties of conventional composite plate structures. Purpose: The free vibration characteristics of the three-phase composite thin plate reinforced synergistically by graphene platelets (GPLs) and carbon fibers are studied in this paper, and we also analyze the influences of the content changes of different reinforcements on the natural frequencies and mode shapes of the three-phase composite thin plate. Methods: The effective material properties of the three-phase composite material are calculated according to a combination of the Halpin–Tsai model and the micromechanics approach. The separation method of variables is used to obtain the natural frequencies and mode shapes of the three-phase composite thin plate under different boundary conditions. The accuracy of results from the separation method of variables is verified by comparison with the references. Conclusions: The synergistic effect of GPLs and carbon fibers can increase the natural frequencies of a composite thin plate under different boundary conditions. The mode shape transformation phenomena mostly appear in the higher order vibrations of the three-phase composite thin plate when the GPLs content increases. The appearance of mode shape transformation is accompanied by a change in the rate of frequency growth. These results have important theoretical significance for a widespread engineering application of the three-phase composite structure. [ABSTRACT FROM AUTHOR]

In this paper, low-velocity impact resistance for composite laminates is introduced. The resistance function for the parameters of low-velocity impact performs 2-order Taylor's series expansion. The orthogonal design and Latin hypercube design are presented and their strongpoint and shortcoming are also indicated. The low-velocity impact simulation model of the composite plate is established. The computed results are compared with the existing standard test from ASTM D7136M-05 and the simulation parameters of the model are modified. By calculating and analyzing typical honeycomb sandwich models with different configurations, the damage-area resistance is extracted from the results. The discrete and abstract variables are treated as continuous integer variables to fit the resistance formula of the composite material. Response surface approximation is used to form a hyper surface formula for parameters. The sensitivity analysis of it reveals that the two most influential factors, related to the resistance definition, which is convenient for the subsequent structural design of the composites. In contrast to the previously defined Taylor's series expansion, the initial coefficients of the resistance formula are obtained. The resistance hyper surface function obtained from the simulation data is used to design the 7-point low-speed impact tests using Latin hypercube design, which employed to verify and validate the simulations, for purposes of saving on the cost of testing and improving the accuracy of analysis. [ABSTRACT FROM AUTHOR]

In this paper, thermal buckling and free vibration of a rectangular plate reinforced with carbon nanotubes (CNT) are investigated within the framework of third-order shear deformation theory (TSDT). CNT distribution along the thickness direction of the plate is uniformly or functionally graded. The equivalent properties of the reinforced composite plate are calculated based on the extended rule of mixture. Governing equations of motion are derived using the Hamilton principle. Obtained governing differential equations are analyzed by utilizing Fourier series expansion along the longitudinal and latitudinal direction for simply supported edges boundary conditions whereas for other edges boundary conditions we used the differential quadrature method (DQM) to solve numerically. Validation of the present formulation is assessed by comparing the results with those reported in the open literature. The effect of CNT volume fraction, the different patterns of CNT distribution, temperature difference, aspect ratio, and thickness-to-length ratio on buckling and vibration behavior of carbon nanotube-reinforced composite (CNTRC) plate is studied. The numerical illustration reveals that in the FG-X pattern of CNT distribution natural frequency and thermal buckling load is more significant compared with the other patterns of CNT distribution. [ABSTRACT FROM AUTHOR]

The influence of weights is usually ignored in the study of nonlinear vibrations of plates. In this paper, the effect of structure weights on the nonlinear vibration of a composite circular plate with a rigid body is presented. The nonlinear governing equations are derived from the generalized Hamilton's principle and the von Kármán plate theory. The equilibrium configurations due to weights are determined and validated by the finite element method (FEM). A nonlinear model for the vibration around the equilibrium configuration is established. Moreover, the natural frequencies and amplitude-frequency responses of harmonically forced vibrations are calculated. The study shows that the structure weights introduce additional linear and quadratic nonlinear terms into the dynamical model. This leads to interesting phenomena. For example, considering weights increases the natural frequency. Furthermore, when the influence of weights is considered, the vibration response of the plate becomes asymmetrical. [ABSTRACT FROM AUTHOR]

In this paper, the seismic design factors for uncoupled composite plate shear walls/concrete filled (C-PSW/CF), a.k.a. SpeedCore, are verified by conducting a study using FEMA methodology. These are the seismic response modification factor, R, the deflection amplification factor, Cd, and the overstrength factor, Ωo; and their values for C-PSW/CF are specified as 6.5, 5.5, and 2.5, respectively. A study was needed, as these factors for uncoupled C-PSW/CFs, included in ASCE 7 since as far back as its 2000 edition, were chosen solely based on the seismic performance of similar structural systems and engineering judgment of the committee members. For this study, four archetypes with planar walls and three archetypes with C-shaped C-PSW/CF walls were chosen. Two different damage measures (DM) were chosen for this study; namely, 3% and 5% maximum interstory drifts. Based on FEMA methodology, all archetypes satisfied the specified performance requirement considering a "good" rating for total system collapse uncertainty (βTOT). [ABSTRACT FROM AUTHOR]

Low-frequency noise pollution in substations has a significant impact on the physical and mental health of workers. Reduction low-frequency noise pollution is an urgent problem to solve for researchers. In this paper, the different structures of Al2O3-polyurethane composites and micro-perforated plate were constructed, and the effects of cavity depth, perforated plate, and foam position on sound absorption properties were comprehensively investigated. The results showed that the position of perforated plate and the arrangement of resonance structure were the two most important factors affecting sound absorption performance. When the sound wave passed through the plexiglass plate–cavity–composites foam–perforated plate in turn, the peak position of sound absorption coefficient was located in the ultra-low frequency range. Meantime, the simulation study showed that the friction between the air column and the cavity wall in the perforated plate can consume sound energy to achieve sound absorption. [ABSTRACT FROM AUTHOR]

The present paper aims to investigate the buckling load of functionally graded carbon-fiber-reinforced polymer (FG-CFRP) composite laminated plates under in-plane loads in a thermal environment. The effective material properties of the CFRP composite are calculated by the Mori–Tanaka homogenization method. The theoretical formulations are based on classical laminate plate theory (CLPT) and the von Kármán equations for large deflections. The governing equations are derived based on the principle of virtual work and then solved through the Navier solution. Results are obtained for the critical buckling load and temperature effect of a simply supported plate subjected to in-plane loading. A detailed numerical study is conducted to provide important insights into the effects of the functionally graded carbon fiber (CF) distribution pattern and volume fraction, total number of layers, temperature, geometrical dimension and lamination angle on the buckling load of functionally carbon-fiber-reinforced composite plates. Finally, the validation is compared with the Reddy and finite element analyses, which show consistency with each other. [ABSTRACT FROM AUTHOR]

Many composite cantilever plate-like structures have found engineering applications in different industries. For attaining a meaningful assessment of the plate vibration characteristics, it is important to have efficient and effective methods for determining the natural frequencies/mode shapes of composite cantilever plates. In this paper, a method formulated on the basis of the Ritz method and a simple first-order shear deformation theory (SFSDT) is presented to analyze the free vibration of thin as well as thick rectangular composite cantilever plates for determining their natural frequencies. In the SFSDT, the total deflection is the sum of two deflection components, namely, bending and through-thickness shear-deformation-induced deflections. The successful application of the Ritz method together with the SFSDT for the free vibration analysis of thick composite plates relies on the selection of two independent sets of characteristic functions for the bending and through-thickness shear-deformation-induced deflections, respectively, to satisfy the requirements for the displacement and force conditions at the fixed edge of the plate. The novelty of the proposed method is that two independent sets of characteristic functions, namely, polynomials and trigonometric functions, which satisfy the displacement and force conditions at the fixed edge have been identified and used in the variational method to construct the eigenvalue problem for extracting the modal characteristics (natural frequencies and mode shapes) of the plate. It has been shown that the uses of the selected characteristic functions can produce excellent natural frequencies for both thin and thick composite cantilever plates. Some existing theoretical and experimental natural frequencies of thin as well as thick composite plates have been used to demonstrate the accuracy of the proposed method in predicting natural frequencies. The significant effects of through-thickness shear deformation on the natural frequencies of composite cantilever plates are studied to show the merit of the present method. Finally, for illustrating the application of the proposed method in free vibration analysis, a novel procedure established on the basis of the sensitivity analysis of natural frequencies is presented to assess the material degradation of composite cantilever plates. The numerical examples have shown that fewer than 10 iterations are required in the identification process to produce a good estimation of the current value for each material constant. [ABSTRACT FROM AUTHOR]

In this paper, free vibration of rotating functionally graded (FG) porous eccentric semi-annular (ESA) and eccentric annular (EA) plates reinforced with graphene nanoplatelets (GPLs) in a thermal environment is solved with the help of transformed differential quadrature method (TDQM). Symmetrical and asymmetrical distributions are considered for both the porosity and the graphene nanoplatelets; the estimation of the Young's modulus is conducted by the model of Halpin–Tsai. A higher-order shear deformation theory is considered as the basis for the employment of the Hamilton's principle for the derivation of both the initial equations of the plates-up to the dynamic equilibrium point and the oscillation phenomena afterward. The method of TDQ utilizes a conformal mapping in order to obtain the DQ weighting coefficients and then discretizes the partial differential equations of the motion, as well as the boundary conditions; this discretization takes place in the physical domain directly. The results indicate that the employed numerical approach is advantageous in high solution accuracy in addition to fast convergence rate. Furthermore, the variation of the natural frequencies of the FG plates with different boundary conditions is investigated by taking into account the influences of several parameters: the geometry, such as eccentricity, thickness ratio, radius ratio; the material, such as the type of porosity and GPLs, the porosity parameter and the weight fraction of GPLs, and other parameters, such as temperature difference and rotating speed. [ABSTRACT FROM AUTHOR]

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Conductive polymer composites (CPCs) have been identified as viable replacements for graphite and metals for polymer electrolyte membrane fuel cell (PEMFC) bipolar plates (BPs). One important factor, apart from composite formulation, that affects the quality and properties of CPC BPs is the processing route. Therefore, understanding the possible processing methods for different matrix–filler combinations and their effects on the quality and properties of the plates can help in controlling and improving the final performance of BPs. This paper reviews the blending and molding techniques for CPC BPs, with a focus on relationship between formulation and processing method. The effects of processing route and conditions on microstructural features of CPC BPs, which affect the performance of the plates are also discussed. Finally, directions for further studies with potential to advance the development of quality and high‐performance CPC BPs are highlighted. Identified key areas for further research include control of filler orientation to improve through‐plane conductivity, correlation between processing parameters and dimensional accuracy of molded plates, and additive manufacturing of composite BPs. [ABSTRACT FROM AUTHOR]

We studied electromechanical fields in a composite plate with flexoelectric and piezomagnetic layers. The governing equations and complete boundary conditions are proposed in terms of the couple stress theory to characterize the size-dependent effects and flexoelectric effects. The constitutive relations of centrosymmetric cubic and hexagonal crystals are both provided. To demonstrate the newly developed model, the static bending and forced vibration problems of a simply supported rectangular plate are studied with the aid of Navier's technique. Numerical results showed that various deformed shapes and electric potential distributions in the current microplate can be effectively manipulated by varying the magnitude of magnetic fields or flexoelectric coefficients. The relevant electromechanical properties can also be adjusted by altering the thickness ratio of the piezomagnetic and flexoelectric layers, which leads to a maximum value of the displacement or electric potential for an optimal thickness ratio. This paper provides an innovative idea for non-contact flexoelectric applications when magnetic fields are involved. [ABSTRACT FROM AUTHOR]

In this paper, experiments and numerical simulations were used to study the mechanical properties of all-C/C composite hybrid bonded/bolted joints. Experiments were conducted to investigate the failure mechanisms, modes, and strengths of composite single-lap joints, namely, bolted joints with and without bonds. The results demonstrated that the failure mode of all-C/C composite mechanical joints was bolt shear failure, while the failure mode of the bonded joints was cohesive force failure. In hybrid bonded/bolted joints, cohesive force failure of the adhesive layer and bolt shear failure have both been noted. The C/C composite plates of all joints were not discovered to have any evident deterioration. The loaddisplacement curve of the hybrid joints was a double-peak curve, the first peak load corresponds to bonding failure, and the second peak load corresponds to bolt failure. For the failure process, mode, and strength of hybrid (bonded/bolted) joints, a 3D progressive damage finite element model was proposed. It is based on the nonlinear finite element code ABAQUS and Hashion failure criteria. The VUMAT subroutine compiled Hashion failure criteria to simulate the damage of fiber and matrix in the composite material. Furthermore, the adhesive layer's failure was simulated using the cohesive element. Comparing failure loads and failure modes to the outcomes of experiments served to validate the model. The gradual damage evolution process and failure mechanism of bonded and hybrid bonded/bolted joints were determined, as well as the mechanism by which the cohesive layer influences the mechanical properties of the hybrid bonded/bolted joints. On the mechanical characteristics of composite joints, the impacts of bolt diameter and adhesive layer modulus were investigated. [ABSTRACT FROM AUTHOR]

Certain bamboo species have mechanical properties that are compatible with construction material. Despite this, their low shear strength, the presence of nodes in their culms, and their circular geometry inhibit the expansion of the use of this material as construction material. One technique that can solve these problems is glued laminated bamboo (GLB). Based on such findings, this paper aims to evaluate the physical and mechanical properties of glued laminated bamboo of the Dendrocalamus giganteus species. Two glues were used: resorcinolformaldehyde (PRF) and polyvinyl acetate (PVAc). The following physical and mechanical characterization tests were performed on glued laminated bamboo: water absorption, density, compression parallel to fiber direction, tension parallel to fiber direction, shear parallel to the glue layer, shear parallel to fiber direction, and bending. The results, analyzed using statistical models, showed that the GLB has physical and mechanical properties comparable to those of hardwoods. [ABSTRACT FROM AUTHOR]

Co‐cured damping composite structures have broad application prospects in high‐tech fields such as aerospace and space vehicles because of their low weight, large damping, and sufficient stiffness. In order to improve dynamic properties of conventional composite structures, a new type of damping composites embedded with multilayer viscoelastic film is proposed in this paper. Based on the complex modulus theory and vibration mechanics of composite plates and shells, vibration differential equation of composite plates with multilayer viscoelastic film is derived. The constitutive relation of the complex structure is established. The consistency of theoretical derivation and numerical simulation results provides a reference for the optimization of dynamic performance of damping sandwich composites. The effects of the distribution of viscoelastic film and the geometric structure parameters on dynamic performance of co‐cured damping composites are also discussed. The results show that the embedding of multi‐layer viscoelastic film can greatly enhance the loss factors of co‐cured composite structures under same damping layer thickness. This work lays a foundation for optimization of dynamic performance of lightweight and large damping composite structures. [ABSTRACT FROM AUTHOR]

Delamination is one of the most common types of damage/defect in carbon/glass fiber reinforced composites and many researchers use frequency-wavenumber analysis to detect delamination. There are large fluctuations in amplitudes when Lamb wave propagates in composite plate, so that it is hard to precisely identify the boundary of delamination simply from the change of wavenumber. This paper has presented an algorithm based on logarithm of wavenumber amplitude to detect the delamination in carbon fiber plate with high precision. In wavenumber spectra after logarithm processing, the wavenumber amplitudes at delamination boundary can be significantly amplified and the resulting curve of sum of amplitudes can be used to effectively identify the boundary. In this paper, the principle of the logarithm of amplitude algorithm has been introduced and the effectiveness of the algorithm in delamination identification has been validated by finite element simulations and physical experiments. Compared with conventional algorithms, the proposed algorithm can effectively identify the boundary with better accuracy (less than 5%) and has decent identification stability under different depths of delamination. Our research has great potential for solving the challenge in precise identification of delamination boundary. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to investigate the electrochemical corrosion behavior of a five-layer Al alloy composites (4343/4047/3003/4047/4343) with a thickness of 0.2 mm in NaCl solution. Design/methodology/approach: Electrochemical impedance spectroscopy, polarization curve and morphology analyses were used to study the corrosion behavior of the Al alloy composites from cross-sectional and plane directions. Findings: The corrosion resistance of the surface from the plane direction was higher than that from the cross sections. Si-enrich particles were observed in the outer 4047/4343 layer, and AlFeCuMnBi phases were identified in the core 3003 layer. The galvanic coupling between the Si-enrich particle and the Al matrix accelerated the dissolution Al matrix. Originality/value: This work lays the experimental foundation for corrosion mechanism of the Al alloy composite plate. [ABSTRACT FROM AUTHOR]

This paper deals with the natural frequency and stability of axially moving functionally graded carbon nanotube-reinforced composite (FG-CNTRC) rectangular thin plates. Based on Reddy's first-order shear deformation theory, the partial differential equations of motion for axially moving FG-CNTRC plates in thermal environment are derived by Hamilton's principle and discretized by the Galerkin method. The in-plane displacement and inertia of the plate are retained in the dynamic model. By solving the complex eigenvalues of the gyroscope system, the variations of natural frequencies of the axially moving FG-CNTRC plates with axial moving velocity are obtained, and the stability of the plates is analyzed. The validity of the present model is verified by comparing the natural frequencies and the critical divergence velocity of the axially moving plate with the existing results in literature. The divergence and flutter type of instability, critical divergence velocity, and critical flutter velocity are studied. The numerical results reveal the effects of CNT distribution, volume fraction, aspect ratio, width-to-thickness ratio, and temperature rise on the natural frequencies of the plates. Additionally, the effects of geometry parameters on the critical divergence velocity and critical flutter velocity of axially moving FG-CNTRC plates are studied by plotting the instability regions. [ABSTRACT FROM AUTHOR]

This paper investigates the frequency response of a smart sandwich plate made of magnetic face sheets and reinforced core with nanofibers. The effective elastic properties of composite core reinforced with carbon nanotube are estimated by the extended rule of Mixture. The orthotropic visco-Pasternak foundation is examined to study orthotropic angle, damping coefficient, normal, and shear modulus. The top and bottom face sheets of the sandwich are magnetic and their vibrations are controlled by a feedback control system and magnetomechanical couplings. Also, the sandwich plate is subjected to the compression and extension in-plane forces in both x and y directions. Five coupled equations of motion are derived using Hamilton's principle. These equations are solved by the differential quadrature method. The analysis performed by the third-order shear deformation theory (Reddy's theory) shows useful details of the effective parameters such in-plane forces, modulus of elastic foundation, coreto- face sheet thickness ratio and controller effect of velocity feedback gain on the dimensionless frequency of the sandwich plate. The analysis of such structures can be discussed in the military, aerospace and civil industries. [ABSTRACT FROM AUTHOR]

Purpose: Ti-Al composite plates have been used in aerospace and other important fields for specific purposes in recent years. However, relatively few studies have concentrated on Ti-Al additive manufacturing because during additive manufacturing process the local fusion and mixing of Ti/Al are inevitable. These areas where Ti and Al are mixed locally, especially interface, could easily generate high residual stresses and cracks. This study aims to manufacture Ti-Al functionally graded material and investigate the interaction of interface. Design/methodology/approach: In this study, Ti6Al4V/AlSi10Mg functionally graded materials were fabricated by laser based directed energy deposition (L-DED) and a strategy using V interlayer to relieve interfacial stress was investigated. Findings: The area between the two materials was divided into transition zone (TZ) and remelting zone (RZ). The phase distribution, microstructure and micro-Vickers hardness of the TZ and RZ were investigated. Typical intermetallic compounds (IMCs) such as TiAl3, Ti3Al and Ti5Si3 were found in both composites. The addition of V interlayer promoted the homogenization of IMCs near interface and led to the formation of new phases like V5Si3 and Al3V. Originality/value: The solidification process near the interface of Ti-Al functionally graded material and the possible generation of different phases were described. The result of this paper proved the feasibility of manufacturing Ti-Al functionally graded material by L-DED. [ABSTRACT FROM AUTHOR]

This paper presents a data-driven structural health monitoring (SHM) method by the use of so-called reduced-order models relying on an offline training/online use for unidirectional fiber and matrix failure detection in a 3D woven composite plate. During the offline phase (or learning) a dataset of possible damage localization, fiber and matrix failure ratios is generated through high-fidelity simulations (ABAQUS software). Then, a reduced model in a lower-dimensional approximation subspace based on the so-called sparse proper generalized decomposition (sPGD) is constructed. The parametrized approach of the sPGD method reduces the computational burden associated with a high-fidelity solver and allows a faster evaluation of all possible failure configurations. However, during the testing phase, it turns out that classical sPGD fails to capture the influence of the damage localization on the solution. To alleviate the just-referred difficulties, the present work proposes an adaptive sPGD. First, a change of variable is carried out to place all the damage areas on the same reference region, where an adapted interpolation can be done. During the online use, an optimization algorithm is employed with numerical experiments to evaluate the damage localization and damage ratio which allow us to define the health state of the structure. [ABSTRACT FROM AUTHOR]

This study investigates the axisymmetric postbuckling of functionally graded graphene platelets reinforced composite (FG-GPLRC) annular plates resting on nonlinear elastic medium in thermal environment. Five kinds of graphene platelets (GPLs) distribution patterns including U -pattern, X -pattern, O -pattern, A -pattern, and V -pattern have been considered. The nonlinear equilibrium equations and associated boundary conditions are obtained based upon the Mindlin plate theory. The governing equations are solved via the generalized differential quadrature method (GDQM). Afterwards, the direct iterative method is implemented to accomplish postbuckling loads using the buckling mode deflection. In order to confirm the accuracy of the present model, comparisons between our data with those published in the available literature are put forth. Eventually, this paper emphasizes the impact of diverse parameters such as geometrical parameters of the structure, GPLs patterns and their geometric, GPLs weight fraction, boundary conditions, elastic medium's parameters and temperature change on the buckling and postbuckling response of nanocomposite annular plates. It can be found that elastic medium overshadows the applicability of distribution patterns and weight fraction of GPLs. [ABSTRACT FROM AUTHOR]

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Without regarding interlayer continuity of transverse shear stresses in the displacement expressions, traditional higher-order plate theories have difficulty in predicting continuous shear stress fields accurately for multilayered functionally graded carbon nanotube-reinforced composite (FG-CNTRC) plates with independent CNT distributions in each layer. In this paper, a new higher-order continuous shear stress multilayered plate model is developed for high-accuracy analysis of FG-CNTRC plates. In the theoretical formulation, higher-order interpolation functions and piecewise descriptions are adopted for transverse shear stress fields. By fulfilling the interlayer continuity of shear stresses and displacements, the displacement expressions for FG-CNTRC plates are formulated. The accuracy of the proposed model is determined by two kinds of parameters: the order of assumed transverse shear stress fields and the number of subdivisions. Compared with traditional higher-order theories, the proposed model can accurately predict continuous transverse shear stresses for FG-CNTRC plates with different CNT configurations by constitutive relations directly. Additionally, a four-node rectangular plate element associated with the proposed model is formulated. Results show that the proposed model agrees well with the exact solutions and results from ANSYS. With the same amount of calculation, the proposed higher-order model has higher accuracy than the model with more subdivisions, especially for asymmetric plates with discontinuous CNT ply angle. [ABSTRACT FROM AUTHOR]

Purpose: This paper presents the effect of damage in the composite substrate on the controlled response of a smart composite plate. Further, the effective location of piezo patches to control the vibration of a composite plate has also been studied. Method: Two different bending modes have been considered in the study, namely, longitudinal bending and twisting. A negative velocity feedback algorithm has been employed to obtain the controlled response of the smart plate. Using the linear constitutive relations, a layer-by-layer finite element (FE) formulation has been developed for the dynamic analysis. The validation of the formulation has been carried out by comparing the natural frequencies and vibration control response with the results from the literature. Conclusion: It can be seen from the study that the damage below the sensor is influencing the controlled response of the plate more than that of the damage below the actuator. [ABSTRACT FROM AUTHOR]

This paper aims to study the influence of key design parameters (e.g., reinforcement ratio, cover thickness, stud spacing, and thickness of the ultra-high-performance concrete (UHPC) layer) on the longitudinal and transverse bending performance, as well as the cracking load and ultimate bearing capacity calculation theory of steel–UHPC lightweight composite deck (LWCD) structure. Four transverse bending tests and four longitudinal bending tests on steel–UHPC composite plates and steel–UHPC composite beams were conducted, respectively. The refined finite element models of components with different key design parameters based on ABAQUS were established. The influences of different key design parameters on the transverse and longitudinal flexural behaviors (e.g., load-mid-span displacement curve, cracking stress, stiffness, elastic limit load, critical slip load, ultimate bearing capacity and ductility) were compared and analyzed in detail. The ultimate bearing capacity can be improved by increasing the thickness of UHPC layer and the reinforcement ratio of longitudinal reinforcement, and reducing the cover thickness and the spacing of studs. According to the longitudinal bending characteristics of the steel–UHPC lightweight composite deck structure, the calculation formulas for the cracking load and the ultimate bearing capacity of the steel–UHPC composite beam are proposed, and the calculated values are in good agreement with test results (the errors are basically within 10%), which is convenient for practical engineering applications. [ABSTRACT FROM AUTHOR]

A finite element dynamic model of the sandwich composite plate was developed based on classical laminate theory and Hamilton's principle. A 4-node, 7-degree-of-freedom three-layer plate cell is constructed to simulate the interaction between the substrate, the viscoelastic damping layer, and the piezoelectric material layer. Among them, the viscoelastic layer is referred to as the complex constant shear modulus model, and the equivalent Rayleigh damping is introduced to represent the damping of the substrate. The established dynamics model has too many degrees of freedom, and the obtained dynamics model has good controllability and observability after adopting the joint reduced-order method of dynamic condensation in physical space and equilibrium in state space. The optimal quadratic (LQR) controller is designed for the active control of the sandwich panel, and the parameters of the controller parameters, the thickness of the viscoelastic layer, and the optimal covering position of the sandwich panel are optimized through simulation analysis. The results show that the finite element model established in this paper is still valid under different boundary conditions and different covering methods, and the model can still accurately and reliably represent the dynamic characteristics of the original system after using the joint step-down method. Under different excitation signals and different boundary conditions, the LQR control can effectively suppress the vibration of the sandwich plate. The optimal cover position of the sandwich plate is near the solid support end and far from the free-degree end. The parameters of controller parameters and viscoelastic layer thickness are optimized from several angles, respectively, and a reasonable optimization scheme can be selected according to the actual requirements. [ABSTRACT FROM AUTHOR]

This paper deals with the formulation of a novel four-node quadrilateral finite element based on the first-order shear deformation theory and using the strain-based approach for static and free vibration responses of composite plates. The developed element has five degrees of freedom per node and its displacement functions contain higher-order terms that satisfy the rigid body modes and are based on assumed strains satisfying compatibility equations. The efficiency of the present element is demonstrated by applying it to sandwich and symmetric/antisymmetric laminated composite plates with various shapes, boundary conditions, side-to-thickness ratios, stacking sequences, fiber orientation angles, and different types of loads. The obtained results are compared with published analytical and numerical solutions that have proved excellent accuracy and efficiency in predicting bending and free vibration of laminated composite plates and have shown that this element is free of shear locking. [ABSTRACT FROM AUTHOR]

This paper presents a coupled thermoelastic finite element formulation for static and dynamic analysis of composite laminated plates with embedded active shape memory alloy (SMA) wires, which accounts for both the phase transformation and the nonlinearity effects of SMA wires. The equations of motion are obtained by using Hamilton's principle and first-order shear deformation theory (FSDT). Furthermore, based on Brinson's one-dimensional phase transformation constitutive law, a novel coupled thermoelastic finite element model that enables analysis of the SMA hybrid composite (SMAHC) plate is developed. The accuracy and efficiency of the developed computational model for analysis of SMAHC plates are reinforced by comparing theoretical predictions with data available from the literature. The results of the numerical examples also show the ability of the proposed model to predict the thermal-mechanical behavior of SMAHC plates in accordance with SMA's hysteresis behavior. In addition, based on the proposed model, the influence of temperature as well as SMA volume fraction, pre-strain value, boundary condition and layup sequence on the static bending and free vibration behavior of the SMAHC plates is investigated in detail. The results of parametric analysis show that the variations of both static deflection and natural frequency of the SMAHC plate over temperature exhibit a nonmonotonic behavior. [ABSTRACT FROM AUTHOR]

This paper develops a new homogenization method for free vibration problems of periodic composite plates. In this new method, three-dimensional (3D) periodic plates are equivalent to Reissner–Mindlin plates with both effective stiffnesses and effective inertia coefficients. The effective stiffnesses for the dynamic problems are the same as those for the static problems, and they can be achieved by the equivalence principle of macro- and microscopic internal virtual work. To fully take the inertia effects into account, the effective inertia coefficients including the effective translational, translational–rotational and rotational inertias are determined by the two-scale equivalence principle of kinetic energies under three rigid modes. In addition, cell size effects in the thickness direction of composite plates are investigated by using the proposed method and the asymptotic homogenization method (AHM). Numerical experiments validate the effectiveness of the proposed equivalent method for different scale factors, and show that the rotational inertia cannot be ignored for out-of-plane deformations, especially for higher-order modes. Besides, numerical comparisons show that the cell size effects are not negligible when using the AHM to analyze the out-of-plane deformations, and three or more repeated unit cells in the thickness direction are required to ensure accuracy. [ABSTRACT FROM AUTHOR]

Numerical and experimental research programs have been carried out to investigate the effect of scaling on the tensile strength of notched composites. This paper presents a computational study of scaled open-hole tensile tests using the Discrete Ply Model (DPM) method. This finite element model is discrete, and only a small number of parameters are required from experimental characterization tests. Experimental and numerical strength values are compared here, and reveal that DPM simulations tend to slightly overestimate strength values, with an average discrepancy of 9.7%. However, DPM Results show that such modeling simulates both the reduction in strength when specimen size is increased for sublaminate level scaled specimens, where failure is fiber dominated, and the increase in strength when specimen size is increased for ply level scaled specimens, where failure is delamination dominated. In all cases, increasing the total thickness of the specimen leads to a decrease in strength and this effect is dominant over the effect of increasing hole diameter. As well as the variation in strength, three distinct failure mechanisms are observed: fiber failure with extensive matrix damage (pull-out failure), fiber failure with little or no matrix damage (brittle failure) and delamination failure. Comparisons with experiments demonstrate that tensile strengths, damage propagation scenarios and failure patterns are predicted with acceptable accuracy. [ABSTRACT FROM AUTHOR]

Contact delamination damage easily occurs inside the composite. The extension and accumulation of the damage occupy most of the time from damage appearance to failure. However, the anisotropy of materials and the small size of early damage make accurate detection difficult. In this paper, a non-elliptical probability imaging (NEPI) method based on nonlinear ultrasonic guided waves is proposed for the delamination damage detection in anisotropic composites. Firstly, the anisotropic characteristics of the composite are analyzed theoretically, and the velocity in all directions is obtained by numerical simulation. Secondly, the arrival time is obtained by the intersection of the upper and lower envelope fitting lines, and nonlinear coefficient is calculated based on the smooth pseudo Wigner–Ville distribution (SPWVD). Then, the time coefficient (C T) and nonlinear damage index (NDI) are defined and applied in the NEPI. By comparison with a reference point, the problem that the damage location of anisotropic composite cannot be solved analytically is avoided skillfully. Finally, the NEPI method is used to present the damage. The experiment results show that the NEPI method can accurately display the damage location. The sensitivity and reliability of NDI based on SPWVD are further verified by comparison with damage index of scattered signal and time–frequency analysis methods such as fast Fourier transform, short-time Fourier transform, and S-transform. The proposed NEPI method based on nonlinear ultrasonic guided waves can detect the delamination damage with good location accuracy and high damage sensitivity. [ABSTRACT FROM AUTHOR]

In this paper, for the first time, the deep learning technique of the artificial neural network method is used to determine the free vibration parameters of the rectangular bistable composite plates. For this purpose, first, the static and free vibration behaviours of a cross-ply bistable composite plate are studied using analytical, finite element and experimental methods. By comparing them, it is turned out that there is a considerable difference among obtained natural frequencies so that the analytical method is only able to determine the fourth natural frequency and cannot estimate the first three natural frequencies. To solve this problem, the deep neural network is employed to model the modal parameters of the bistable laminate as an explicit mathematical relationship that can be generalized to the other bistable composite plates. This mathematical relation makes it possible to obtain the natural frequencies in each of the stable configurations based on the geometric dimensions of the plate. In the following that, the inverse problem method is considered and the mode management capability is investigated. A fast swarm intelligence algorithm called firefly algorithm is used to optimize the optimization function of the mode management problem. Mode management using the evolutionary algorithm provides the appropriate physical dimensions of the plate according to the scenarios for natural frequencies arrangement. The results are validated by comparing them with those obtained by the finite element method and experiment test, which results show that this method estimates the modal parameters with high accuracy. The method used in this paper can also be applied to determine the modal parameters of other morphing structures. [ABSTRACT FROM AUTHOR]

This paper introduced the triangulation method using the relations of the signal magnitudes and distances between each sensor and impact location. In order to extract the useful feature having good correlation with these distances, the time of arrival (TOA) data of sensor signal was applied. Using the signal magnitudes and TOA data, the effective features could be derived for estimating the distances between each sensor and impact location. For investigating this suggested algorithm, low-velocity impact experiments were carried out on the composite stiffened plate as a target structure. The acoustic emission signals were captured by the commercial high-speed optical fiber sensing system. From the impact signals on the baseline locations (30 points), the regression model was constructed for estimating the distances of impact location from each sensor on the target area. Then, through the non-baseline signals (20 points), the validations of constructed regression model were performed. As a result, this regression model is able to accurately predict the AE source locations on the non-baseline cases. [ABSTRACT FROM AUTHOR]

In order to achieve high efficiency and low damage processing of hard and brittle materials, composite ultrasonic vibration-assisted face grinding (CUVAFG) has been proposed by comprehensively combining the high efficiency of axial ultrasonic vibration grinding (UVAG) and the low damage of elliptic ultrasonic vibration grinding (EVAG). However, the three-dimensional ultrasonic vibration brings about a more complicated machining mechanism than the previous ultrasonic vibration-assisted grinding methodology. Hence, in order to explore the grinding mechanism in deep, this paper first developed a new model of undeformed chip thickness for CUVAFG from the perspectives of the kinematic mechanism and elastic-plastic deformation mechanism. Then the influences of different processing parameters on interference rate and undeformed chip thickness were further confirmed. Finally, CUVAFG experiments of silicon carbide (SiC) ceramics were conducted to study the relationship between the undeformed chip thickness and the resultant grinding forces, specific grinding energy, ground surface morphology and roughness, and subsurface damage. It is found from the experimental results that the critical chip thickness of brittle-ductile transition in CUVAFG is between 0.31 and 0.35 μm. As the undeformed chip thickness is less than the critical value, the grinding forces and the specific grinding energy increases with the undeformed chip thickness, but the ground surface roughness decreases with improved surface morphology and shallow subsurface damage. After exceeding the critical value, the grinding force remains unchanged, the specific grinding energy decreases, and ground surface roughness increases with deteriorated surface morphology and deepened subsurface damage. For the purpose of good machining surface integrity, it is essential to guarantee that the undeformed chip thickness is less than the critical value. The computational and experimental results have demonstrated the contribution of the developed undeformed chip thickness model to understanding the grinding performance of hard and brittle material by CUVAFG. • A novel undeformed chip thickness model that considers the elastic-plastic deformation of workpiece material is proposed. • The interference area and rate are proposed to explain the influence of processing parameters on undeformed chip thickness. • The critical undeformed chip thickness of brittle-ductile transition for silicon carbide by CUVAFG is confirmed in the range of 0.31–0.35 μm. • The depth of the subsurface damage layer increases from 2.1 μm to 66.7 μm with the increase of undeformed chip thickness. • The grinding forces, ground surface roughness, and specific grinding energy are reduced by 30 %, 42 %, and 93 %, respectively. [ABSTRACT FROM AUTHOR]