Mechanics of Materials最新文献

{"title":"Temperature-dependent electrical breakdown model of solid dielectric materials based on the high-temperature fracture mechanics","authors":"Ruzhuan Wang ,&nbsp;Weiguo Li","doi":"10.1016/j.mechmat.2026.105607","DOIUrl":"10.1016/j.mechmat.2026.105607","url":null,"abstract":"<div><div>The high-temperature electrical breakdown strength is a critical indicator limiting the reliability of solid dielectric materials and their overall capacitor structure applications. Despite its crucial role, theoretical characterizing this high-temperature electrical breakdown strength is a challenging scientific issue that demands urgent attention. To address this gap, our work introduces a novel concept and model of temperature-dependent critical energy release rate corresponding to the electrical breakdown, which is based on the theory of energy storage limit. This concept, in turn, leads to the development of a temperature-dependent breakdown criterion that offers a more comprehensive understanding of the breakdown mechanisms at high temperature. Furthermore, we establish a temperature-dependent theoretical model and phase-field model for analyzing the electrical breakdown strength under the self-generated thermo-mechano-electrical coupling. This model takes into account temperature, electrically induced stress, the characteristic size of the electrical breakdown channel, and porosity. The developed breakdown criterion and theoretical model are verified by the remarkable agreements between the model predictions, phase-field simulation results and the experimental results from our work and the literature. The remarkable feature of the developed model is that, without any fitting, the quantitative characterization of coupling effects of temperature and microstructure evolution on the breakdown strength is realized. This work has developed a theory for high-temperature electrical breakdown, based on our research group's long-term work in the field of high-temperature fracture mechanics.</div></div>","PeriodicalId":18296,"journal":{"name":"Mechanics of Materials","volume":"215 ","pages":"Article 105607"},"PeriodicalIF":4.1,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146024180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling solvent diffusion in amorphous polymers spanning glass transition region","authors":"Junwei Xu ,&nbsp;Kunquan Wang ,&nbsp;Rui Xiao ,&nbsp;Lu Dai","doi":"10.1016/j.mechmat.2025.105584","DOIUrl":"10.1016/j.mechmat.2025.105584","url":null,"abstract":"<div><div>Diffusion of solvent molecules into amorphous networks exhibits distinct behaviors based on polymer states. The diffusion behavior of solvents in elastomers or rubber-like polymers is classified as Case I diffusion, also known as Fickian diffusion. In contrast, diffusion of solvent molecules in glassy polymers differs significantly from that in rubbery polymers, characterized by a distinct boundary between a swollen region and a non-swollen region. This type of diffusion is termed Case II diffusion. In this study, a model is developed to simultaneously characterize both Fickian and non-Fickian diffusion behaviors. The free energy comprises three components: an equilibrium component arising from entropic elasticity due to network deformation of the polymer chains, a non-equilibrium component due to the viscoelastic contribution, and the free energy associated with the mixing of solvents and polymer chains. The free volume theory is introduced to describe the influence of glass transition on solvent diffusion and viscosity. Specifically, as free volume increases, the solvent diffusion rate rises rapidly, while viscosity decreases significantly. Finite element simulations are further performed to investigate the effects of various parameters on diffusion behavior, with a particular focus on revealing the central mechanisms related with the Case II diffusion. This work enhances the understanding of complex diffusion behaviors in amorphous polymers across the glass transition region.</div></div>","PeriodicalId":18296,"journal":{"name":"Mechanics of Materials","volume":"215 ","pages":"Article 105584"},"PeriodicalIF":4.1,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145895939","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of blood flow–clot interaction using a fibrinogen concentration–dependent hyperelastic constitutive model","authors":"Zhipeng Zhao ,&nbsp;Xiaomin Zhang ,&nbsp;Qiong Wu ,&nbsp;Linlin Zhang ,&nbsp;Libo Zhao ,&nbsp;Ke Cheng ,&nbsp;Yuanlin Ma ,&nbsp;Ge Tang","doi":"10.1016/j.mechmat.2025.105577","DOIUrl":"10.1016/j.mechmat.2025.105577","url":null,"abstract":"<div><div>Blood clot formation is a critical mechanism in physiological functioning; however, abnormal changes in the mechanical properties of blood clots can trigger various pathological responses. The fibrin network of blood clots is the greatest contributor to their structural integrity, and the microstructural characteristics of the network determine the mechanical responses of clots under different loading conditions. First, a fibrinogen concentration–dependent hyperelastic constitutive model was developed by establishing the relationship between fibrinogen concentration and modulus through microstructural characterization (mesh size) of the fibrin networks. Subsequently, uniaxial compression and shear tests were conducted on the clots with varying fibrinogen concentrations to validate the model. Both theoretical and experimental studies revealed that the clot–strengthening effect of fibrinogen diminished with increasing concentration. Finally, the proposed constitutive model was applied to numerical simulations of blood flow–clot interactions. We observed that the maximum shear stress was concentrated at the flow-facing edges of the clots. By integrating the maximum shear stress and deformation magnitude, a detachment risk index (<em>RI</em>) was defined, and its behavior was systematically explored through parameter scanning. The results demonstrated that <em>RI</em> shows a linear correlation with flow velocity and clot size. Moreover, the fibrinogen concentration exhibited a dual-effect mechanism when the shear stress weighting coefficient was relatively high (<em>α</em> ≥ 0.4): (1) For low–concentration clots, the detachment risk increased with concentration, with shear stress as the dominant mechanism. (2) For high–concentration clots, the detachment risk decreased with increasing concentration, and deformation response was the governing mechanism.</div></div>","PeriodicalId":18296,"journal":{"name":"Mechanics of Materials","volume":"214 ","pages":"Article 105577"},"PeriodicalIF":4.1,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145841194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A model of the human cornea as a hydrated, fluid-saturated medium","authors":"Alessandro Giammarini,&nbsp;Anna Pandolfi","doi":"10.1016/j.mechmat.2025.105586","DOIUrl":"10.1016/j.mechmat.2025.105586","url":null,"abstract":"<div><div>We introduce a new model of the human corneal stroma, regarded as a fluid-saturated continuum, able to describe surface flattening and thickness thinning observed in several pathological conditions. In contrast with more common approaches that describe the human cornea as a quasi-incompressible hyperelastic medium, eventually including micro-structured anisotropy and heterogeneity, here we focus on the multi-phase nature of the tissue, where the content of water reaches about 78% in weight. The study is motivated by the fact that, although purely mechanical continuum models have been demonstrated to be satisfactory and accurate at predicting physiological behaviors, they have not been able to capture the geometrical features of tissue degeneration clearly associated to a reduction of the fluid content in the stroma, such thinning and loss of curvature. Here, we model the cornea as a fully saturated mixture of a solid phase and a fluid phase, in principle without restricting the formulation to specific assumptions on the actual inhomogeneous nature of both phases. The focus of the study is to understand whether a multiphysics model is capable of explaining, in terms of fluid flux imbalance, such as ectasia and keratoconus. As a first attempt in this direction, we make simple isotropic constitutive assumptions for both phases.</div></div>","PeriodicalId":18296,"journal":{"name":"Mechanics of Materials","volume":"214 ","pages":"Article 105586"},"PeriodicalIF":4.1,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145841193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Crystal plasticity approach of necking in stretching rods","authors":"Emilie Lam ,&nbsp;Jean-Lin Dequiedt","doi":"10.1016/j.mechmat.2025.105578","DOIUrl":"10.1016/j.mechmat.2025.105578","url":null,"abstract":"<div><div>The fragmentation of a ductile metal rod under dynamic extension simulating an expanding ring is initiated by multiple necking. This is a structural instability justified by the mechanics at the macroscopic scale. However, the computation of the plastic flow at the mesoscale, i.e. the one of the crystal aggregate, applying crystal plasticity modelling inside grains provides new insights on both the overall process and the plastic slip activity in the most developed necks, potentially controlling their subsequent failure. Full field simulations of FCC copper polycrystal rods show a large scatter of inter-neck spacing and neck intensity, in contrast with the macroscopic concept of a dominant periodic instability mode. Scatter of the neck number and positions for different grain and crystal orientation instances is also significant even though they have no clear connection with initial grain-scale strain map. The necking pattern is next found to evolve with subsequent neck competition and arrest of the less pronounced necks consistently with a Mott type obscuration mechanism. The number of active necks in the late stage is nevertheless weakly sensitive to grain structure. Furthermore, when strain concentrates in the most developed necks, plastic slip activity takes place in a narrow zone of elongated grains submitted to very high plastic deformations. These grains undergo significant lattice rotations and thus mobilize continuously evolving sets of slip systems. Owing to slip system interactions, critical shear stresses still increase and saturate in the very late localization stage, together with the development of a marked texture. In-grain strain localization, which is a potential seed of neck failure, is addressed by using a finite deformation linear stability analysis. Band type localization modes are displayed with time increasing growth rate. In the late stage, such modes involve both elastic and plastic deformation components and develop almost perpendicularly to the stretching direction. They also induce significant lattice rotation and may trigger the formation of laminated subgrain structures.</div></div>","PeriodicalId":18296,"journal":{"name":"Mechanics of Materials","volume":"214 ","pages":"Article 105578"},"PeriodicalIF":4.1,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145841212","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bridging the scales of mechanical failure in solids","authors":"Bradley Dodd ,&nbsp;Marc Meyers ,&nbsp;Naresh Thadhani ,&nbsp;Min Zhou ,&nbsp;Yujie Wei","doi":"10.1016/j.mechmat.2025.105563","DOIUrl":"10.1016/j.mechmat.2025.105563","url":null,"abstract":"","PeriodicalId":18296,"journal":{"name":"Mechanics of Materials","volume":"214 ","pages":"Article 105563"},"PeriodicalIF":4.1,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146034737","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hierarchical relaxation governed by memory effect in azobenzene-based supramolecular photosensitive hydrogel","authors":"Xinyu Liu,&nbsp;Wei Rao,&nbsp;Junjun Shang,&nbsp;Xia Liu,&nbsp;Jing Zhang,&nbsp;Qingsheng Yang","doi":"10.1016/j.mechmat.2025.105595","DOIUrl":"10.1016/j.mechmat.2025.105595","url":null,"abstract":"<div><div>Azobenzene (AZO)-based supramolecular photosensitive hydrogels exhibit great potential in biomedical and flexible electronics fields owing to their light-induced gel-sol transitions. To investigate the dynamic rheological mechanisms of these hydrogels before and after irradiation, we develop a fractional four-element rheological model that accounts for hierarchical relaxation governed by memory effects. This model incorporates multiscale microstructural dynamics, including segmental mobility, water molecular motions, single chain conformational changes, and network deformations, offering a new perspective on the rheological behavior. The model's validity is verified through quantitative simulations of storage and loss moduli for representative AZO-based hydrogel systems. Parameter analysis reveals that memory effects arising from complex micro-hierarchical structures determine the nonlinear frequency responses of storage/loss moduli. Furthermore, loss factor analysis reveals a key finding. The mismatch between hierarchical structural motions and external loads, which varies with frequency, regulates the governing microstructure during gel-sol transitions. This regulation causes a shift from network-dominated to segment/water molecule-dominated behaviors. As frequency increases, the transition changes from unidirectional to bidirectional. Time-domain analysis of the model also clarifies low-frequency response mechanisms. It shows that gel-sol transitions are driven by two concurrent mechanisms: modulation of interchain slippage and alteration of entanglement point number density. This study not only reveals dynamic mechanisms in photosensitive hydrogels, but also provides a predictive tool for precisely engineering their effect irradiation on rheological behaviors.</div></div>","PeriodicalId":18296,"journal":{"name":"Mechanics of Materials","volume":"214 ","pages":"Article 105595"},"PeriodicalIF":4.1,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145881435","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on the dynamics evaluation method of thermal-friction coupled sensitivity for typical high-energy explosives","authors":"Pu Zhao ,&nbsp;Bao Rong ,&nbsp;Jiawen Yang ,&nbsp;Mingming Shi ,&nbsp;Xiaoli Dong ,&nbsp;Xiaoting Rui ,&nbsp;Zixuan Pan ,&nbsp;Chao Li","doi":"10.1016/j.mechmat.2025.105583","DOIUrl":"10.1016/j.mechmat.2025.105583","url":null,"abstract":"<div><div>Heat and friction are critical factors that contribute to the ignition and detonation of energetic materials. The existing friction sensitivity testing method faces limitations, including high risk, large testing volumes, long cycles, high costs, and significant environmental influences. These limitations make it difficult to quickly analyze and evaluate the friction safety of energetic materials through experiments alone. For typical high-energy explosives, this study examines their mechanical behavior under friction and the impact of chemical reactions on the temperature field. Based on finite element theory, chemical reaction kinetics, and viscoelastic-plastic mechanics, the conservation equations of mass, momentum, and energy are first established. A viscoelastic-plastic statistical crack constitutive model and the Arrhenius equation are then introduced, ultimately forming a thermal-friction coupled sensitivity dynamic model. Friction sensitivity tests are conducted under different ambient temperatures using a self-developed thermal-friction coupled sensitivity testing device. The simulation results show good agreement with the experimental data, with an average error of 3.74 %. The effects of friction conditions on friction sensitivity are analyzed, revealing that increases in friction load, friction coefficient, initial material temperature, and motion speed all lead to higher sensitivity. Based on the response surface methodology, a rapid prediction model for the friction sensitivity threshold of typical explosives under different temperatures is established, with an average prediction error of 6.04 %. This study enables rapid prediction and analysis of the friction sensitivity of high-energy explosives under different temperature conditions. It holds significant value for evaluating the friction safety of high-energy explosives during production, transportation, storage, and application. It provides theoretical guidance for preventing accidental ignition or explosion caused by external friction.</div></div>","PeriodicalId":18296,"journal":{"name":"Mechanics of Materials","volume":"214 ","pages":"Article 105583"},"PeriodicalIF":4.1,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145841192","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental and theoretical studies on the effect of initial curvature of substrate in thin film peeling","authors":"Qingning Yang,&nbsp;Yueguang Wei","doi":"10.1016/j.mechmat.2025.105576","DOIUrl":"10.1016/j.mechmat.2025.105576","url":null,"abstract":"<div><div>Classic peeling theories provide a baseline for understanding interfacial adhesion but are limited to flat substrates where the initial curvature is zero. This study extends the analysis to the more general case of curved surfaces by investigating how a substrate's initial curvature governs thin film peeling. We first present physical peeling tests on cylindrical substrates with varying initial curvatures. These experiments reveal a key departure from flat-surface behavior: the peeling force is not constant but systematically changes with the crack tip position. To explain this phenomenon, we derive a series expansion model from energy principles that quantitatively links the peeling force to the local initial curvature and peeling angle. The model's predictions show excellent agreement with our experimental results and are further validated by finite element (FE) simulations for substrates with parabolic and cosine-shaped profiles. A central finding is that the peeling response is predominantly linear for substrates with small initial curvature but becomes highly non-linear as the initial curvature increases. This non-linear behavior is accurately captured by the higher-order terms of our series solution, demonstrating its effectiveness in predicting the mechanics of peeling from substrates with arbitrary initial curvature.</div></div>","PeriodicalId":18296,"journal":{"name":"Mechanics of Materials","volume":"214 ","pages":"Article 105576"},"PeriodicalIF":4.1,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145841195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correlation function-dependent bounds and Mori–Tanaka effective stiffness estimates: A numerical validation study on biphase transversely isotropic composites","authors":"Anna Gorgogianni,&nbsp;Chloé Arson","doi":"10.1016/j.mechmat.2025.105580","DOIUrl":"10.1016/j.mechmat.2025.105580","url":null,"abstract":"<div><div>This paper investigates the validity of two different analytical homogenization methods: the Mori–Tanaka mean-field theory and Milton’s correlation function-dependent bounds. We focus on biphase linearly elastic transversely isotropic composites. The composites consist of a matrix reinforced with long fibers of either circular or irregular cross section shapes formed by overlapping circles, with different degrees of radius polydispersity. The Mori–Tanaka effective stiffness depends on the phase moduli, volume fractions, and on a few geometric descriptors of the fibers that can be readily evaluated. In contrast, the computation of Milton’s bounds requires finer knowledge of the microstructure, in terms of two and three-point spatial correlation functions, which are not always analytically tractable. We thus consider very specific random microstructure geometries with known correlation functions. The effective moduli estimates of the two methods are validated against the results of numerical homogenization using the finite element method. It is shown that the Mori–Tanaka predictions of the effective transverse bulk modulus are significantly more accurate than those of the transverse and axial shear moduli. In addition, the predictions of the scheme generally deteriorate with an increasing fiber volume fraction. By contrast, the average of Milton’s upper and lower bounds provides a highly accurate estimate for all three independent effective moduli, without any limitation on the fiber concentration. This study highlights the indisputable effect of the spatial correlation functions on the effective properties of composites, and aspires to pave the way towards the development of more predictive, correlation function-dependent homogenization methods.</div></div>","PeriodicalId":18296,"journal":{"name":"Mechanics of Materials","volume":"214 ","pages":"Article 105580"},"PeriodicalIF":4.1,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145881439","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}