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Highlights This study discussed the effects of different contents of Nickel‐titanium alloy particles (NiTip) on the vibration properties of carbon fiber reinforced polymers (CFRP) and further verified the test results by dynamic mechanical analysis tests while analyzing the effects of NiTip on the thermal stability of CFRP. The test results showed that 1.0 vol% of NiTip was the most effective in reducing the vibration transmission rate of the CFRP while improving its thermal stability. The modal of the CFRP composite cantilever beam is analyzed using the finite element method. In addition, the mechanical properties of CFRP with different NiTip contents were tested, including tensile, flexural, interlaminar shear and impact properties. The test results showed that 1.0 vol% of NiTip was most effective in improving the flexural properties, tensile properties and interlayer shear properties of CFRP. At the same time, 3.0 vol% of NiTip was most effective in improving the impact properties of CFRP. In addition, the fracture surfaces of CFRP reinforced with different NiTip contents were microanalysed to elucidate the enhancement mechanism. This study developed a multifunctional composite material with both vibration damping and high performance. These results provide essential guidelines for the optimal design and application of NiTip reinforced composites in vibration control, structural and aerospace applications. The effects of different Nickel‐titanium alloy particles (NiTip) levels on the vibration and mechanical properties of carbon fiber reinforced polymers (CFRP) were investigated. The influence of NiTip addition on the loss factor and thermal stability of CFRP was evaluated. SEM images were used to analyze the influence mechanism of uniform dispersion of NiTip on the reduction of vibration transmission rate of CFRP and the improvement of mechanical properties of CFRP. [ABSTRACT FROM AUTHOR]

Ti-6Al-4V titanium alloy is known as one of the most difficult metallic materials to machine, and the machined surface residual stress distribution significantly affects properties such as static strength, fatigue strength, corrosion resistance, etc. This study utilized finite element software Abaqus 2020 to simulate the two-step cutting process of titanium alloy, incorporating stages of cooling, unloading, and de-constraining of the workpiece. The chip morphology and cutting force obtained from orthogonal cutting tests were used to validate the finite element model. Results from the orthogonal cutting simulations revealed that with increasing cutting speed and the tool rake angle, the residual stress undergoes a transition from compressive to tensile stress. To achieve greater residual compressive stress during machining, it is advisable to opt for a negative rake angle coupled with a lower cutting speed. Additionally, in two-step machining of titanium alloy, the initial cutting step exerts a profound influence on the subsequent cutting step, thereby shortening the evolution time of the Mises stress, equivalent plastic strain, and stiffness damage equivalent in the subsequent cutting step. These results contribute to optimizing titanium alloy machining processes by providing insights into controlling residual stress, ultimately enhancing product quality and performance of structural part of titanium alloy. [ABSTRACT FROM AUTHOR]

The mechanical behaviors of hybrid metal–composite joints with different protrusion densities were investigated by combining numerical and experimental methods. High-fidelity finite element models that considered the failure modes of all components were developed, and specimens based on metal additive manufacturing technology were tested under quasi-static tensile load to verify the numerical calculations. The results showed that the load capacity and the dominant fracture mode of joints were significantly affected by the metal protrusion density. The failure mechanisms of joints under different protrusion conditions exhibited a clear difference, which proved the possibility of an optimal and functional joint design. [ABSTRACT FROM AUTHOR]

• Vibration control of interconnected functionally graded fluid-conveying pipe is investigated. • A vibration experiment is established to explore NiTiNOL-steel damping ability. • Modal analysis is solved through the Rayleigh-Ritz approach and finite element method. • Investigation of amplitude-frequency response of the structure is carried out. • NiTiNOL-steel has significant nonlinear vibration control capabilities. In this study, an exploratory vibration experiment is established and an interconnected functionally graded material (FGM) pipeline system is installed. This experiment represents the first time that NiTiNOL-steel wire ropes (NiTi-ST) are applied to FGM pipeline system. And the experimental results demonstrate that the NiTi-ST has a practical vibration damping effect. Based on the experiment, a further theoretical pipeline system model is created. The effects of fluid velocity, temperature difference, and clamp stiffness on the modal and response of the pipeline system are added. The modal analysis part is solved through the implementation of the Rayleigh-Ritz approach using a set of modified orthogonal polynomials. In order to verify the accuracy of the Raylei-Ritz calculations, the finite element method (FEM) is also used. The response analysis part is solved through the Galerkin truncation method (GTM) and harmonic balance method (HBM). To match the harmonic balance solutions, the Runge-Kutta method (RK) are adopted. The results of the response analysis reveal that NiTi-ST demonstrates significant nonlinear vibration control capabilities to the interconnected FGM pipeline system under various conditions. [ABSTRACT FROM AUTHOR]

This paper focuses on the vibration control of an L-shaped composite structure, which is a simplified part of the motor support structure in an electric airplane. NiTiNOL steel wire rope (NiTi-ST) is employed as the vibration control mechanism. The study begins with a natural frequency and modal analysis using the Rayleigh-Ritz approach, which is subsequently validated using finite element analysis and experimental hammering methods. The dynamical equations are derived through the Lagrange method and then discretized using the Galerkin truncation method (GTM). Vibration responses of the simplified model are obtained through the harmonic balance method (HBM), and these results are confirmed through validation with the Runge-Kutta method (RKM). Based on the theoretical analysis, the experiments are carried out to optimize the vibration control scheme of L-shaped composite beam. The results demonstrates that the NiTi-ST wire rope effectively controls vibrations without affecting the system's natural frequency. [ABSTRACT FROM AUTHOR]

• Vibration control of interconnected composite beams is investigated. • Modal analysis is solved through the Rayleigh-Ritz approach and finite element method. • Investigation of frequency response of the structure is investigated. • A vibration experiment is established to explore NiTiNOL-steel damping ability. This paper presents a comprehensive theoretical investigation and experimental validation of vibration and nonlinear vibration control in interconnected composite beams with fixed ends operating within a thermal environment. The study employs the Rayleigh-Ritz method, utilizing a series of orthogonal polynomials as interpolation basis functions to derive the vibration mode functions of the composite structure under thermal conditions. Furthermore, the motion control equation for the system is derived based on Lagrange's equation. These equations of motion are then simplified using the Galerkin method, leading to ordinary differential equations. The response of the system is subsequently computed using the harmonic balance method and validated through the Runge-Kutta method. Finally, experimental results confirm that the NiTiNOL-steel wire rope effectively controls the vibration of interconnected composite beams in a thermal environment and is consistent with the theoretical results. [ABSTRACT FROM AUTHOR]

Large thermal residual stresses in coatings during the coating deposition process may easily lead to coating delamination of coated carbide tools in machining. In order to reduce the possibility of coating delamination during the tool failure process, a theoretical method was proposed and a numerical method was constructed for the coating design of WC-Co cemented carbide cutting tools. The thermal residual stresses of multi-layered coatings were analytically modeled based on equivalent parameters of coating properties, and the stress distribution of coatings are simulated by Finite element method (FEM). The theoretically calculated results and the FEM simulated results were verified and in good agreement with the experimental test results. The effects of coating thickness, tool substrate, coating type and interlayer were investigated by the proposed geometric and FEM model. Based on the evaluations of matchability of tool substrate and tool coatings, the basic principles of tool coating design were proposed. This provides theoretical basis for the selection and design of coatings of cutting tools in high-speed machining. [ABSTRACT FROM AUTHOR]

• Presented a general formulation for the analysis of composite laminated wing-box structures. • Explain the mechanism of joint stiffness on the coupled form of the structure. • Revealed the dynamic sensitive temperature scope of CLWBSs. For the sake of achieving the goal of ultra-low or even zero carbon emissions during flight, hydrogen-electric aircraft has been receiving increasing emphasis. Nevertheless, the hydrogen-electric aircraft owns an all-composite fuselage configuration and is subjected hygrothermal environment, which have a significant effect on the aircraft dynamics, especially for wing structure. In this study, an improved orthogonal polynomial solution based on the Rayleigh-Ritz method is developed for the dynamic analysis of composite laminated wing-box structures (CLWBSs) of hydrogen-electric aircraft with humid and hot environment and elastic boundary. In this solution approach, the potential energy, kinetic energy, elastic potential energy and hygrothermal potential energy of CLWBSs are derived from the framework of Kirchhoff thin plate hypothesis. A set of artificial springs is imported to the free edges of CLWBSs to simulate the elastic boundary and connection between two plates. The convergence, accuracy and computational efficiency of the proposed formulation are validated by experiment and finite element analysis. The effect of the coupling parameters and the elastic boundaries due to flexible composite fuselage in hygrothermal environment created by the hydrogen fuel cells are systematically investigated which have been confirmed by theoretical research, finite element analysis and experiment. The related findings indicate that the present approach provided an effective formulation for the vibration analysis and optimization of flexible composite wing-box structures. It can be applied in the field of aerospace and navigation industry at the same time. [Display omitted] [ABSTRACT FROM AUTHOR]

To meet the requirements of vibration control for composite structures, the NiTiNOL steel wire ropes (NiTi-ST) is selected to control the vibration of the composite laminate. The dynamical modeling is built by integrating the composite laminate with the modified Bouc-Wen model. The dynamical model is discretized by Galerkin truncation method (GTM), and theoretical analysis is carried out using the harmonic balance method (HBM), Runge-Kutta method (RK) and finite element method (FEM). Based on the results of dynamical modeling and theoretical analysis, an experimental device is designed and manufactured. The results show that the NiTi-ST has excellent vibration control ability for composite laminate, and the impact on the natural frequency of the system is small. [ABSTRACT FROM AUTHOR]

When high speed machining polycrystalline metal, severe plastic deformation usually undergoes in the machined surface layer, accompanied by the microstructural variation of the crystallographic orientation. In the present paper, the machined surface plastic deformation and microstructural texture evolution during high speed machining of titanium alloy Ti-6Al-4V were investigated using finite element method (FEM) simulation. Firstly, a two dimensional FEM model was established, and was validated in terms of cutting forces and chip shape characteristics with experimental results of orthogonal machining. The plastic deformation on the machined surface was analyzed on the basis of finite element simulation. Results revealed that the plastic shear strain was much larger than the other strains in different directions. In addition, the variation of plastic shear strain and strain rate versus cutting time was obtained. When the feed rate was constant, the strain decreased and the maximum strain rate increased as cutting speed increased. Finally, the machined surface texture was simulated and analyzed using the Viscoplastic Self-consistent (VPSC) program based on the variation of plastic shear strain and strain rate, combined with polycrystalline plasticity theory. The machined surface texture evolution during machining was expressed by pole figures and orientation distribution function (ODF) diagrams. And the cylinder texture was identified from the pole figures. Four typical shear textures, including Y, C 1 , C 2 , and B fiber textures, were obtained from the ODF diagrams. Meanwhile, the orientation density of texture decreased with the increasing of cutting speed. [ABSTRACT FROM AUTHOR]