Nan Gu , Wen Zhang , Deyong Zhou , Meiying Yang , Xinghao Lu , Xincun Zhuang , Zhen Zhao
{"title":"Prediction of necking instability under tension-shear stress state based on updated modified maximum force criterion","authors":"Nan Gu , Wen Zhang , Deyong Zhou , Meiying Yang , Xinghao Lu , Xincun Zhuang , Zhen Zhao","doi":"10.1016/j.ijsolstr.2025.113319","DOIUrl":"10.1016/j.ijsolstr.2025.113319","url":null,"abstract":"<div><div>During the process from sheet forming to failure, the material might undergo uniform deformation, diffused necking (DN), localized necking (LN), and finally ductile fracture (DF). Researchers have found that a competitive mechanism exists between the LN-induced failure mode and DF-induced failure mode in the ductile metallic material. For tension shear (TS) stress state, most studies are focused on the DF prediction. This paper is concerned with necking instability in TS region and the prediction of necking failures. An updated modified maximum force criterion (uMMFC) model is proposed by considering the effect of in-plane shear stress, in which the strain path at LN onset under TS is no longer plane strain tension but varies with the initial path. Meanwhile, the effect of through-thickness normal stress is introduced into the uMMFC model. By comparing the forming limits obtained from the uMMFC, the original MMFC and the experimental results under uniaxial tension tests and Nakajima tests, it is concluded that the uMMFC model can well predict the forming limit curve under TS. Furthermore, the uMMFC model with the introduction of strain path modification after DN demonstrates a further improvement in prediction accuracy.</div></div>","PeriodicalId":14311,"journal":{"name":"International Journal of Solids and Structures","volume":"313 ","pages":"Article 113319"},"PeriodicalIF":3.4,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143528602","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Deformation and energy absorption characteristics of graded auxetic metamaterials featuring peanut-shaped perforations under in-plane compression","authors":"Zhuo Zhang, Yongpeng Lei, Hui Wang","doi":"10.1016/j.ijsolstr.2025.113318","DOIUrl":"10.1016/j.ijsolstr.2025.113318","url":null,"abstract":"<div><div>The auxetic metamaterials perforated by peanut-shaped holes have been paid much attention recently due to the advantages in alleviating stress concentration, tuning negative Poisson’s ratio (NPR) and stiffness, and reducing material usage. However, few studies pay attention to their graded designs, which have exhibited promising applications in natural biomaterials. In this study, the innovative design of graded auxetic metamaterials featuring peanut-shaped perforations is explored, emphasizing their potential in customizing deformation and energy absorption. By exploring four distinct graded types, including unidirectional gradient (UG), inward gradient (IG), outward gradient (OG) and alternate gradient (AG) and three gradient-controlling ways, including porosity (K), shape coefficient (M), and porosity and shape coefficient changing simultaneously (KM), 12 unique graded structures are developed. The graded specimens under quasi-static compression exhibit distinct deformation behaviors. Subsequently, the graded structures are thoroughly explored by the validated finite element model and the deformation mode, dynamic Poisson’s ratio and energy absorption capacity are comprehensively investigated. Compared to the uniform structure, the distribution and quantity of NPR bands strongly depend on the perforation’s size and the gradient types. Furthermore, UG-KM can significantly amplify the NPR effect, achieving a maximum enhancement of 14.32%. In contrast, AG-K can considerably diminish the NPR effect, with a maximum reduction of 19.37%. Additionally, type OG exhibit superior energy absorption characteristics, with mean stress and specific energy absorption increasing by up to 28.89% and 46.73%, respectively. The findings provide an effective strategy for designing the auxetic metamaterials with tunable deformation and energy absorption characteristics.</div></div>","PeriodicalId":14311,"journal":{"name":"International Journal of Solids and Structures","volume":"313 ","pages":"Article 113318"},"PeriodicalIF":3.4,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143520505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yong Li , Yunpeng Guo , Yuwei Zhang , Wei Feng , Kai Zhang , Xin Wang , Fuqian Yang
{"title":"Modeling of diffusion-induced inter-/transgranular cracking in polycrystal NCM particles: Effects of external force and boundary constraints","authors":"Yong Li , Yunpeng Guo , Yuwei Zhang , Wei Feng , Kai Zhang , Xin Wang , Fuqian Yang","doi":"10.1016/j.ijsolstr.2025.113300","DOIUrl":"10.1016/j.ijsolstr.2025.113300","url":null,"abstract":"<div><div>Experimental results have evidenced that appropriate external forces can mitigate structural degradation and damage of active particles during electrochemical cycling of metal-ion batteries. Currently, there are few studies on structural degradation and damage of active particles under concurrent action of diffusion and external loading. Using finite-discrete element method (FDEM), we analyze diffusion-induced cracking in a polycrystal NCM (lithium nickel manganese cobalt oxide) particle under three different configurations: traction-free boundary, rigid confinement to opposite ends, and external loading to opposite ends under constant influx. The numerical results illustrate that appropriate external loading can suppress the nucleation and propagation of cracks induced by the diffusion of solute atoms and retard structural degradation/damage of polycrystal NCM particles. Increasing the amount of solute atoms and applying excessive external loading can promote the nucleation and propagation of cracks in polycrystal NCM particles due to large contact deformation and the deformation induced by the diffusion of solute atoms, which escalates structural degradation/damage of the electrodes in metal-ion batteries.</div></div>","PeriodicalId":14311,"journal":{"name":"International Journal of Solids and Structures","volume":"313 ","pages":"Article 113300"},"PeriodicalIF":3.4,"publicationDate":"2025-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143512484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Bojan Starman , Tomaž Pepelnjak , Andraž Maček , Miroslav Halilovič , Sam Coppieters
{"title":"Inverse calibration of out-of-plane shear anisotropy parameters of sheet metal","authors":"Bojan Starman , Tomaž Pepelnjak , Andraž Maček , Miroslav Halilovič , Sam Coppieters","doi":"10.1016/j.ijsolstr.2025.113313","DOIUrl":"10.1016/j.ijsolstr.2025.113313","url":null,"abstract":"<div><div>The accurate description of sheet metal forming processes such as blanking, riveting, incremental forming, and ironing strongly depends on understanding the material’s through-thickness shear resistance and plastic behavior. A three-dimensional model of plastic anisotropy is required to capture this behavior, but calibrating the out-of-plane shear parameters is often challenging. Researchers frequently assume isotropy or set the in-plane and out-of-plane shear parameters equal. More advanced approaches use a crystal plasticity model, which also requires calibration based on available material texture data. In this work, we introduce an out-of-plane shear test procedure that combines a macromechanical test with digital image correlation to inversely calibrate the shear anisotropy parameters of the YLD2004-18p yield function. This method efficiently characterizes both in-plane and out-of-plane shear anisotropy in medium-thick sheet metals.</div></div>","PeriodicalId":14311,"journal":{"name":"International Journal of Solids and Structures","volume":"313 ","pages":"Article 113313"},"PeriodicalIF":3.4,"publicationDate":"2025-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143512485","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Energy-based PINNs using the element integral approach and their enhancement for solid mechanics problems","authors":"Junwei Chen , Jianxiang Ma , Zhi Zhao , Xiaoping Zhou","doi":"10.1016/j.ijsolstr.2025.113315","DOIUrl":"10.1016/j.ijsolstr.2025.113315","url":null,"abstract":"<div><div>Despite the growing interest in physics-informed neural networks (PINNs) for computational mechanics, significant challenges remain in their widespread application. This work proposes an energy-based PINN method rooted in the principle of virtual work, which states that the external work done on a system is equal to its strain energy. This proposed method discretizes the model into nodes and constructs elements based on these nodes. The strain energy of each element is computed through numerical integration, and the total strain energy of the model is obtained by summing these elemental contributions. Simultaneously, the external work is calculated based on the nodal forces. These calculations, combined with the principle of virtual work, allow for the definition of the model’s physical properties. A deep neural network (DNN) is then trained to map the model’s coordinates to their corresponding displacements, utilizing the defined physical properties. Furthermore, this paper proposes a method to accelerate the learning process of energy-based PINNs by using a simpler and converged model to speed up convergence and to improve the overall accuracy of more complex models. Numerical results demonstrate that the proposed approach effectively solves stress concentration and singularity problems in solid mechanics with high accuracy.</div></div>","PeriodicalId":14311,"journal":{"name":"International Journal of Solids and Structures","volume":"313 ","pages":"Article 113315"},"PeriodicalIF":3.4,"publicationDate":"2025-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143527358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Green’s functions of size-dependent Timoshenko beams: Gradient elasticity versus stress-driven nonlocal theories","authors":"Noël Challamel , A. Aftabi S.","doi":"10.1016/j.ijsolstr.2025.113308","DOIUrl":"10.1016/j.ijsolstr.2025.113308","url":null,"abstract":"<div><div>In this article, Timoshenko elastic nano-beams modeled by three different models (stress-driven nonlocal integral model, strain gradient elastic model without transversal strain gradient, and strain gradient elastic model with transversal strain gradient effect) are analyzed by the help of Green’s function method. Conventionally, the governing boundary value problem (BVP) for Timoshenko nano-beams consists of two differential equations (DEs) and six boundary conditions (BCs) with two unknown dependent variables, i.e., (1) the cross-sectional rotation function, and (2) the transverse displacement field. In the stress-driven model, this multi-field problem is converted into a new single-field BVP including a single higher order DE with only one dependent variable. Obviously, this recent problem needs some new BCs which are rigorously derived in the second step of formulation. The third, and in fact, the last step of the proposed formulation is to solve the new organized BVP by the means of Green’ function. However, in the strain gradient model, the BVP consists of two six-order DEs with two unknown functions. Also, this problem includes twelve boundary conditions which eight of them are “decoupled” and four of them are “coupled” which should be solved simultaneously. To the best of knowledge to the researchers, the current study is a first successful attempt to solve a BVP with some “coupled” boundary conditions by Green’s function. As an instance, the Green’s function of simply supported Timoshenko nano-beams is obtained for both (1) stress-driven nonlocal integral model, and (2) strain gradient elastic model which, respectively, contain symmetric and non-symmetric kernels. Alongside the graphical presentation of the Green’s functions, the results of all models are presented for several loading including the distributed loads expressed by the help of polynomials with higher degrees (equal or more than two) and sinusoidal distributed loading.</div></div>","PeriodicalId":14311,"journal":{"name":"International Journal of Solids and Structures","volume":"314 ","pages":"Article 113308"},"PeriodicalIF":3.4,"publicationDate":"2025-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143682377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yutian Du , Zejian Xu , Hongzhi Hu , Mengyu Su , Ang Hu , Fenglei Huang
{"title":"Constitutive modelling and validating of annealed copper under various stress states, strain rates and temperatures","authors":"Yutian Du , Zejian Xu , Hongzhi Hu , Mengyu Su , Ang Hu , Fenglei Huang","doi":"10.1016/j.ijsolstr.2025.113312","DOIUrl":"10.1016/j.ijsolstr.2025.113312","url":null,"abstract":"<div><div>Metallic materials and structures are often subjected to a wide range of strain, strain rate, temperature and stress state during the engineering application. In order to study the plastic and deformation characteristics of metallic materials under complex stress states, it is necessary to use a constitutive model that considers the effects of stress states. Based on shear specimens suitable for hydraulic Instron testing machines and Hopkinson bar systems (SHPB and SHTB), the compression-shear and tension-shear specimens are designed to achieve complex stress states. Through a combination of test and parallel finite element simulation, stress–strain curves of the material under various stress states were obtained. Additionally, mechanical property tests were conducted on specimens under typical stress states (uniaxial compression, uniaxial tension, and shear) at a wide range of strain rates and temperatures. To describe the plastic mechanical behavior of materials, a new plastic constitutive model considering temperature, strain rate, and stress state is proposed. Then the model was embedded into the ABAQUS/Explicit finite element software through the VUMAT user material subroutine for numerical simulation. The performance of the new model was systematically compared and analyzed with that of Johnson-Cook model and Xu et al.’s model. The ability of the prediction of plastic deformation in Taylor impact test was evaluated for different models. The results show that the new constitutive model is suitable for predicting the impact deformation associated with complex strain rates, temperatures, and stress states.</div></div>","PeriodicalId":14311,"journal":{"name":"International Journal of Solids and Structures","volume":"313 ","pages":"Article 113312"},"PeriodicalIF":3.4,"publicationDate":"2025-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143552351","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xiao-Lei Cui , Qianxi Sun , Yichun Wang , Shijian Yuan
{"title":"Measurement and calculation method for circumferential plastic strain ratio of anisotropic aluminum alloy tubes","authors":"Xiao-Lei Cui , Qianxi Sun , Yichun Wang , Shijian Yuan","doi":"10.1016/j.ijsolstr.2025.113311","DOIUrl":"10.1016/j.ijsolstr.2025.113311","url":null,"abstract":"<div><div>To improve the finite element analysis (FEA) accuracy of forming hollow tubular components, it is urgent to determine the circumferential mechanical properties of thin-walled tube blanks, especially the plastic strain ratio <em>r<sub>θ</sub></em>, and further investigate their anisotropic deformation and hardening behaviors. In this paper, a new segment-type ring expansion test (SRET) method was established for directly measuring <em>r<sub>θ</sub></em> based on digital image correlation (DIC). It was shown by theoretical analysis that an approximately uniaxial and uniform stress state can be generated when the number of segments is 12 and the initial width-to-diameter ratio of the specimen is about 0.10. It was experimentally proved that the relative error of the measured <em>r<sub>θ</sub></em> of 304 stainless steel welded tube was less than 1 % compared with the <em>r</em>-value of the original 304 sheet. Then, the <em>r<sub>θ</sub></em> of aluminum alloy (6061) tubes was obtained by the SRET method, and the biaxial tensile deformation of the tubes was realized by a controllable biaxial tension test. It is shown that the axial and circumferential plastic strain ratios were 0.460 and 0.638, respectively. The strain path of equal-biaxial stress deviated from the equal-biaxial strain path, and the strain paths of <em>σ<sub>z</sub></em> / <em>σ<sub>θ</sub></em> = 0.75 and 1.333 (reciprocal) were asymmetrically distributed along the equal-biaxial strain line. These results indicate the tubes’ apparent anisotropic deformation behaviors. Finally, the effect of <em>r<sub>θ</sub></em> and yield criterion on predicting the anisotropic hardening behavior was analyzed using the effective stress–strain curve. The results illustrate that <em>r<sub>θ</sub></em> must be considered, and the Balart89 yield criterion with higher order has higher accuracy compared with the Hill48 yield criterion. This research is significant for improving and evaluating the prediction accuracy of plastic constitutive models.</div></div>","PeriodicalId":14311,"journal":{"name":"International Journal of Solids and Structures","volume":"313 ","pages":"Article 113311"},"PeriodicalIF":3.4,"publicationDate":"2025-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143520506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Ductile damage analysis under extreme low-cycle biaxial shear loadings: Experiments and simulations","authors":"Zhichao Wei , Marleen Harting , Steffen Gerke , Michael Brünig","doi":"10.1016/j.ijsolstr.2025.113292","DOIUrl":"10.1016/j.ijsolstr.2025.113292","url":null,"abstract":"<div><div>This paper addresses the experimental and numerical analysis of ductile damage under extremely low-cycle loading conditions with a large strain range. Shear cyclic loading stress states with stress triaxiality of approximately zero are generated using the biaxially loaded cruciform X0-specimen, with equal positive and negative forces applied to different loading axes. Monotonic and various symmetric cyclic loading patterns are designed to investigate the influence of loading histories on the material response at both macro- and micro-levels. The numerical calculations are performed using a novel anisotropic continuum damage model. For plasticity, the hydrostatic sensitivity Drucker–Prager yield condition with combined hardening is used to characterize the isotropic plastic behavior. Additionally, an anisotropic damage strain tensor that considers stress state influences is used to predict the occurrence and development of damage. Digital image correlation (DIC) technique and scanning electron microscopy (SEM) technique enable comparison of experimental and numerical results in different aspects. The numerical results for load–displacement curves, total strain field, and damage strains agree well with the experimental data, as confirmed by quantitative error analysis in load–displacement curves and statistical analysis of SEM images.</div></div>","PeriodicalId":14311,"journal":{"name":"International Journal of Solids and Structures","volume":"313 ","pages":"Article 113292"},"PeriodicalIF":3.4,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143487457","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zhongtong Wang , Robert J. Wagner , Tianke Chen , Sagar P. Shah , Marianna Maiaru , Meredith N. Silberstein
{"title":"Bond exchange reactions as a paradigm for mitigating residual stress in polymer matrix fiber composites","authors":"Zhongtong Wang , Robert J. Wagner , Tianke Chen , Sagar P. Shah , Marianna Maiaru , Meredith N. Silberstein","doi":"10.1016/j.ijsolstr.2025.113286","DOIUrl":"10.1016/j.ijsolstr.2025.113286","url":null,"abstract":"<div><div>Polymer matrix fiber composites often suffer from residual stresses due to differences in coefficients of thermal expansion between the fibers and resins, as well as contractile strain of the resins during curing. To address residual stress driven composite failure, we propose the use of vitrimers as composite resins, which can undergo thermally activated, stress alleviating, bond exchange reactions (BERs). We conduct fiber Bragg grating measurements for a single glass fiber within bulk vitrimer. These show that the fiber strain in vitrimers with 5% catalyst is significantly lower than in those with 0% catalyst (minimal BER expected) during both curing and post-curing phases. We developed a finite deformation, micromechanically-inspired model that incorporates curing, thermal processes, and BERs, and then implemented this model it into finite element software to simulate stress evolution within single fiber composite systems. The combination of experimental and computational results reveals that BERs can effectively mitigate, but not eliminate, the residual stress in polymer matrix fiber composites.</div></div>","PeriodicalId":14311,"journal":{"name":"International Journal of Solids and Structures","volume":"313 ","pages":"Article 113286"},"PeriodicalIF":3.4,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143508042","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}