International Journal of Mechanical Sciences最新文献

{"title":"Ultrasonic assisted grinding mechanisms of SiCf/SiC composites driven by strain-rate","authors":"Yichuan Ran,&nbsp;Jiansong Sun,&nbsp;Haiqi Sun,&nbsp;Renke Kang,&nbsp;Zhigang Dong,&nbsp;Yan Bao","doi":"10.1016/j.ijmecsci.2025.109926","DOIUrl":"10.1016/j.ijmecsci.2025.109926","url":null,"abstract":"<div><div>Ultrasonic assisted grinding (UAG) is considered an effective method for machining ceramic matrix composites (CMCs). However, the intense dynamic mechanical loads encountered during machining, along with the property disparities among fiber, matrix, and interface, increase both the uncertainty of UAG process and the difficulty in analyzing the material removal mechanism. In this study, the mechanisms underlying ultrasonic vibration were revealed via dynamic mechanical response of SiC_f/SiC composites and energy dissipation principles during machining for the first time. Through experiments with conventional grinding (CG) and UAG, it is discovered that UAG exhibits superior machining performance compared to CG, with reduced surface/subsurface damage, lower grinding forces, and decreased surface roughness. Moreover, UAG effectively minimizes discrepancies among different fiber orientations. Combining the results of dynamic mechanical response and energy dissipation model for chip fragment formation, it is found that the high strain rate induced by ultrasonic vibration promotes the embrittlement of composites. This is manifested by the increased nucleation of microcracks in both fibers and matrix, which inhibit the propagation of interfacial cracks and long cracks. Consequently, the removal modes of fibers, initially through bending or shear fracture, and matrix, initially through breakage, both transition to a pulverization mode. These transitions weaken the interfacial, heterogeneous, and anisotropic effects during machining, thereby achieving high-quality processing of SiC_f/SiC composites. This study enhances the understanding of surface formation and material removal mechanisms. Moreover, it confirms the feasibility of using dynamic mechanical response and energy dissipation principles to investigate material removal mechanisms in the machining of CMCs.</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"287 ","pages":"Article 109926"},"PeriodicalIF":7.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143167438","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An improved Flory's statistical-mechanics model of chain-molecular for compressible polymers","authors":"Xinyuan Wang,&nbsp;Liqun Tang,&nbsp;Yiping Liu,&nbsp;Zejia Liu,&nbsp;Zhenyu Jiang,&nbsp;Licheng Zhou,&nbsp;Bao Yang","doi":"10.1016/j.ijmecsci.2025.109946","DOIUrl":"10.1016/j.ijmecsci.2025.109946","url":null,"abstract":"<div><div>Existing hyperelastic models require a large number of material constants to fully describe the mechanical behavior of compressible polymers, indicating that existing hyperelastic models need to be improved. To address this fundamental problem, we modified the Flory's statistical mechanics model of chain molecular by introducing a generalized multivariate Gaussian distribution of cross-linked units and derived a new Helmholtz free energy expression and macroscopic constitutive equation for polymer networks. The improved Flory's model can not only adaptively describe linear elastic and nonlinear elastic materials, but also unify the form of the constitutive equation whether the material is compressible or not. The experimental results show that the improved Flory's model containing 6 parameters can well describe the mechanical behavior of foam silicone rubber with a volume change of 150 %. Compared with existing models, the improved Flory's model not only does not require the addition of complex volume terms to characterize compressibility, but also has fewer parameters in the constitutive equation. This also shows that the improved Flory's model captures the essence of statistical mechanics of chain molecule well and has better universality.</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"287 ","pages":"Article 109946"},"PeriodicalIF":7.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142975207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prediction model for surface shape of YAG wafers in wafer rotational grinding","authors":"Jinxing Huang,&nbsp;Renke Kang,&nbsp;Zhigang Dong,&nbsp;Shang Gao","doi":"10.1016/j.ijmecsci.2025.109982","DOIUrl":"10.1016/j.ijmecsci.2025.109982","url":null,"abstract":"<div><div>Yttrium aluminum garnet (YAG) wafers are essential for thin disk lasers, requiring extremely low peak-to-valley (PV) values after thinning. Wafer rotational grinding is an efficient thinning method for controlling the surface shape, minimizing the time required for polishing. However, the high hardness of YAG increases grinding forces, which can deform the grinding wheel and compromise the surface shape. This paper presents a novel predictive model for the surface shape PV value of ground YAG wafers to address this issue. Initially, a grinding force model is established by considering material elasticity rebound and the size effect of material hardness. Subsequently, the wheel deformation induced by grinding force is calculated and the results are confirmed with finite element simulation. Furthermore, the effect of wheel deformation on the inclination angle is investigated, and the PV value of the ground surface is calculated. Finally, grinding tests are used to validate the suggested model, and the impact of the grinding settings on the PV value is investigated. The results demonstrate that the PV value of the wafer increases with higher grain size and wheel rotational speed, but decreases with higher workpiece rotational speed and feed rate. Additionally, wafers ground with resin-bond wheels shows lower PV value compared to those ground with vitrified-bond wheels. The experimental results align with theoretical predictions, indicating that the proposed model is accurate. This work improves the understanding for grinding surface shape prediction in wafer rotational grinding and provides valuable guidance for optimizing grinding parameters for YAG wafers.</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"287 ","pages":"Article 109982"},"PeriodicalIF":7.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166649","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental and numerical study of CFRP laminates after seawater immersion","authors":"Yifan Li ,&nbsp;Huiming Ding ,&nbsp;Can Jin ,&nbsp;Zhengli Hua ,&nbsp;Jinyang Zheng","doi":"10.1016/j.ijmecsci.2025.109975","DOIUrl":"10.1016/j.ijmecsci.2025.109975","url":null,"abstract":"<div><div>In this paper, the residual strength of carbon fiber reinforced polymer composites (CFRP) for marine applications has been studied. The seawater absorption tests, regular tensile tests, scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) analysis of CFRP exposed to seawater at 25 °C, 40 °C and 60 °C respectively were conducted. A hydro-mechanical coupling progressive damage model has also been established to predict the mechanical behavior and damage evolution, considering both hydrothermal- and mechanical load-induced damage. The experimental results show that the seawater immersion significantly affects the transverse mechanical properties, while having little effect on the in-plane shear and longitudinal properties. The microstructural comparative analysis indicates that the accelerated moisture absorption, induced by high immersion temperature, increases salt deposition and weakens the adhesion between fiber and matrix. The finite element analysis (FEA) results shows good fidelity, with relative errors not exceeding ±10 % in predicting residual strength. Seawater immersion significantly accelerates matrix tensile damage, increasing its area, but has minimal effect on fiber tensile damage. This model can assist engineers in predicting the durability of composite load-bearing structures in marine environment.</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"287 ","pages":"Article 109975"},"PeriodicalIF":7.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hail impact damage modelling of polymeric core aluminium sandwich panels","authors":"Shuangmin Shi ,&nbsp;Nelson Lam ,&nbsp;Yiwen Cui ,&nbsp;Jia Ming Goh ,&nbsp;Emad Gad ,&nbsp;Lihai Zhang","doi":"10.1016/j.ijmecsci.2025.109995","DOIUrl":"10.1016/j.ijmecsci.2025.109995","url":null,"abstract":"<div><div>Aluminium sandwich panels (ASPs) with polymeric core made up of aluminium face sheets and a polymer-mineral composite core present a more cost-effective solution to building claddings than aluminium alloy because of improved energy efficiency. However, there are uncertainties regarding their resistance to impact by hail. Massive economic losses can be incurred should there be widespread damage resulted from the resistant capacity being exceeded in a hailstorm. This study investigates the resistance of such sandwich cladding panels to hail impact and the damage mechanism. Dynamic tests were conducted in this study by accelerating laboratory-made ice balls of varying sizes and velocities onto the cladding specimens at full scale. An optical 3D scanner was employed to survey indentation distribution at the dented region. Energy absorption of each layer was determined. Knowledge gained from the survey was used to develop an analytical expression for predicting the amount of permanent indentation into ASPs when struck by hail. Images captured by the high-speed camera were used to study the geometric evolution of ice spheres upon impact, with their unique characteristics incorporated into the analytical modelling process to provide a more precise analysis of the contact mechanics. The analytical predictions are shown to match with experimental measurements with discrepancy of within 10%. The presented experimental results along with the newly developed analytical model provide useful insights into the impact resistance of sandwich cladding products for guiding its design to withstand extreme weather conditions.</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"287 ","pages":"Article 109995"},"PeriodicalIF":7.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166654","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamics analysis and multi-objective optimization for a dry friction damper","authors":"Zhonghe Huang ,&nbsp;Chuliang Liu ,&nbsp;Qiao Sun","doi":"10.1016/j.ijmecsci.2025.109930","DOIUrl":"10.1016/j.ijmecsci.2025.109930","url":null,"abstract":"<div><div>This paper presents the optimal design of a dry friction damper for a helicopter tail-rotor driveline, focusing on achieving superior vibration suppression around the first critical speed and enhanced component reliability. The optimization is driven by efficient fitness value calculations and response-based assessments of component wear. A detailed model is developed for the damper featuring a double-layer stator with dual rub-impacts, capturing complex interactions through derived semi-analytical solutions that enable precise and efficient dynamic response analysis. To assess durability, a novel wear metric is proposed, based on solution stability and differentiation of rub-impact patterns. Simulations are conducted to analyze multi-stage damping effects, dual rub-impact response characteristics, and parameter influences on these responses. Using a multi-objective optimization framework that incorporates both the semi-analytical solutions and wear metric, Pareto optimal solutions are generated through two metaheuristic algorithms, identifying distinct parameter regions to guide the development of two optimized damper configurations. These parameter recommendations are implemented through targeted adjustments and structural optimization, resulting in dampers that demonstrate significant improvements in both damping performance and wear reduction.</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"287 ","pages":"Article 109930"},"PeriodicalIF":7.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143167020","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Extended space charge and transport near ion-selective surfaces","authors":"Wei Liu,&nbsp;Yunfan Huang,&nbsp;Moran Wang","doi":"10.1016/j.ijmecsci.2025.109933","DOIUrl":"10.1016/j.ijmecsci.2025.109933","url":null,"abstract":"<div><div>Electroconvective flow near ion-selective surfaces propels movements of ions and water, resulting in intricate phenomena influenced by fine interactions among fluid, voltage, and charge. However, the formation mechanism of the small number of cations in the extended space charge (ESC) near the ion-selective surfaces remains unclear. Herein, the origin of the small number of cations in ESC is investigated using a blockage-nanoslot-bulk structure. Direct numerical simulations of the fully coupled Poisson-Nernst-Planck and Navier-Stokes equations are presented for a blockage-nanoslot-bulk system under the influence of external fields. A strong electric field induced by ion flux is recommended as a critical factor for ESC formation based on transient analysis of the local fluid, voltage, and charges in the intermediate time. Once the ion flux exceeds the limiting current density, the induced strong negative electric field propels a small number of cations at the nanoslot-bulk interface to extend parallelly within a finite region, forming an ESC characterized by a localized peak charge structure. Furthermore, the self-similar extension of the ESC is determined based on variations in the ESC thickness, and the normalized structure of the space charge density was revealed by employing normalized coordinates, which were confirmed by direct numerical simulations. Finally, we showed the effect of the geometric structure on the vortex, demonstrating that the nanoslot structure significantly improves wave number prediction.</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"287 ","pages":"Article 109933"},"PeriodicalIF":7.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143167021","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fatigue-creep design of transpiration cooled nickel gas turbine blades via low order aerothermal-stress and crystal plasticity finite element modelling","authors":"Christos Skamniotis ,&nbsp;Michael van de Noort ,&nbsp;Alan C.F. Cocks ,&nbsp;Peter Ireland","doi":"10.1016/j.ijmecsci.2025.109955","DOIUrl":"10.1016/j.ijmecsci.2025.109955","url":null,"abstract":"<div><div>Transpiration Cooling (TC) systems can substantially improve the fuel efficiency of jet engines by allowing them to run much hotter than current designs allow. However, TC systems require radically new designs where large cyclic thermomechanical stresses and creep-plastic deformation can limit the life of core components. This can only be mitigated through integrated design approaches which simultaneously consider the aerothermal and mechanical performance. We develop here a low order aerothermal-stress model (LOM) which combines first order coolant flow and fluid-solid convective-conductive heat transfer calculations with stress calculations in the solid. The LOM provides rapid answers to crucial design questions: how much cooling air and how many cooling holes are required in gas turbine blades for them to operate safely at a given turbine inlet (hot gas) temperature? The LOM also narrows the range of conditions under which Crystal Plasticity Finite Element (CPFE) simulations may be required for fatigue-creep life assessment at final design stages. Our answer to previous pessimistic views on the practical use of TC is that TC systems can actually work thanks to the threefold benefit of cooling holes in reducing metal temperatures, temperature gradients and effective thermal stresses. CPFE simulations confirm this new conclusion, encouraging the wider use of our hybrid design strategy in turbomachines, hypersonic technologies and fusion reactors as well as the take-up of TC systems to deliver durable hydrogen-fuelled turbines for Net Zero.</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"287 ","pages":"Article 109955"},"PeriodicalIF":7.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143167060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A dynamic compliance matrix method for modeling compliant mechanisms","authors":"Mingxiang Ling ,&nbsp;Jie Zhu ,&nbsp;Shilei Wu ,&nbsp;Lei Yuan ,&nbsp;Xianmin Zhang","doi":"10.1016/j.ijmecsci.2025.109957","DOIUrl":"10.1016/j.ijmecsci.2025.109957","url":null,"abstract":"<div><div>Lagrange's equation is usually combined with the compliance matrix method to solve the dynamics of compliant mechanisms that belongs to a time-domain approach. In contrast, we introduce a dynamic compliance matrix method (DCM) for both kinetostatics and vibration analyses of small-deformation compliant mechanisms in the frequency domain. We discuss in detail under what preconditions the so-called dynamic compliance matrix is valid and how it can be correctly transferred between flexure building blocks. Then, we propose a generalized procedure for the dynamic compliance modeling of serial-parallel chains by virtue of mechanical networks. In essence, such a new concept of DCM has a similar modeling process to traditional static compliance matrix method by mass grounding, but it enables both kinetostatic and dynamic modeling of compliant mechanisms in a pseudo-static way switched by setting the circular frequency to zero as needed. It relies on a matrix summation operation without the requirements of internal force analysis and kinematic calculation, hence is modeling-concise and programming-friendly for complex serial-parallel compliant mechanisms. Two case studies are presented to validate the proposed DCM and discuss its application scopes.</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"287 ","pages":"Article 109957"},"PeriodicalIF":7.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142975234","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A rigid-flexible dynamic model of flexoelectric robotic metamaterials with large in-plane motions","authors":"Gongye Zhang ,&nbsp;Yanjie Mei ,&nbsp;Changwen Mi ,&nbsp;Ernian Pan ,&nbsp;Yilin Qu","doi":"10.1016/j.ijmecsci.2025.109943","DOIUrl":"10.1016/j.ijmecsci.2025.109943","url":null,"abstract":"<div><div>We propose, in this paper, a new rigid-flexible coupling dynamic model for robotic metamaterials. A floating coordinate system is employed to decompose the displacement of the beam. Based on the three-dimensional constitutive equations of center-symmetric flexoelectric materials, the constitutive equations of the flexoelectric beam are derived. The strain, strain gradient, and electric field are expressed in the local coordinate system based on the Euler-Bernoulli beam theory. The velocity and acceleration at any point in the system are determined in the global coordinate system. Through the principle of virtual work, the governing equations and the corresponding boundary conditions for the dynamic coupled flexoelectric beam are established. With the established model, an in-depth analysis is carried out to investigate the relationship between the displacement and the electric field under diverse rigid motions. Numerical results indicate that when the beam is subjected to an impact along the axial direction, an electric field along the same direction will be generated within the beam. When it is subjected to a shear force, an electric field in the thickness direction will be generated. We also find that the magnitude of the generated electric potential is proportional to the magnitude of the applied force. Furthermore, we explore the impact of an external electric field on the deflection of a beam when it is swinging. It is shown that a positive (negative) external electric field, which synchronized with the swing, increases (reduced) the deflection of the beam. Hence, by applying an appropriate external electric field, the maximum deflection within the beam can be tuned. This result is of great significance to the field of intelligent materials and structures. The present work could provide a theoretical basis for the realization of obstacle perception, hybrid force/position control, and active control of deformation by using flexoelectric dielectrics in metamaterial robots.</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"287 ","pages":"Article 109943"},"PeriodicalIF":7.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143167018","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}