Journal of The Mechanics and Physics of Solids最新文献

{"title":"Grain refinement in metal microparticles subjected to high impact velocities","authors":"Chongxi Yuan, Marisol Koslowski","doi":"10.1016/j.jmps.2024.106009","DOIUrl":"https://doi.org/10.1016/j.jmps.2024.106009","url":null,"abstract":"High-strain rate deformation caused by microparticles impacting at high velocities is used to refine the microstructure of metallic materials to the nanocrystalline regime. Under these conditions, metallic targets and particles show a gradient distribution of nanograins, with size increasing away from the impact surface. Some of the mechanisms responsible for the refinement process are still not fully understood. We present finite element simulations of single-crystal and polycrystalline aluminum <mml:math altimg=\"si1.svg\" display=\"inline\"><mml:mrow><mml:mn>20</mml:mn><mml:mspace width=\"1em\"></mml:mspace><mml:mi mathvariant=\"normal\">μ</mml:mi><mml:mi mathvariant=\"normal\">m</mml:mi></mml:mrow></mml:math> particles impacting a sapphire substrate at velocities ranging from 50 m/s to 500 m/s. The model includes finite deformation crystal plasticity, a contact algorithm, and an equation of state for high strain rate response. We study the effect of crystal orientation on the restitution coefficient, the permanent deformation of the particle, and grain refinement. The extreme deformation of the particle during the impact results in a high dislocation density and lattice rotation that develop a microstructure with a gradient distribution of grains that are smaller near the impact surface. The size of the new grains scales linearly with the inverse of the average stress in the particle.","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"53 1","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142867393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanistic cohesive zone laws for fatigue cracks: Nonlinear field projection and in situ synchrotron X-ray diffraction (S-XRD) measurements","authors":"H. Tran, D. Xie, P.K. Liaw, H.B. Chew, Y.F. Gao","doi":"10.1016/j.jmps.2024.106010","DOIUrl":"https://doi.org/10.1016/j.jmps.2024.106010","url":null,"abstract":"A weak interface model with a predefined traction-separation relationship (denoted as the cohesive zone law), when embedded in a bulk solid, is oftentimes adopted to simulate the crack advancement and thus determine the crack resistance under either monotonic or cyclic loading conditions. To-date, various types of loading-unloading irreversibility and hysteresis are only presumed in the cohesive zone law for fatigue crack growth, but without any direct determination from experimental measurements. Using a fine-grained Mg alloy and synchrotron X-ray diffraction (S-XRD) measurements with a sub-millimeter beam, in situ lattice strain mapping can be obtained with the needed resolution to cover both the “messy” process zone as modeled by the cohesive zone law and the “clean” process zone caused by plastic deformation. We extend our previously developed nonlinear field projection method, and create trial elastic fields from the S-XRD-measured elastic strain fields at different loading levels when choosing the fully unloaded state as the new reference. From the Maxwell-Betti's reciprocal theorem, we reconstruct a mechanistic cohesive zone law for fatigue cracks, where the reciprocity gap is governed by the residual stress field at the fully unloaded state. Combining our inverse approach with S-XRD measurements, it is discovered that the fatigue-crack cohesive zone exhibits a bilinear unloading and reloading behavior that is distinctively different than all prior works. This particular form suggests the origin of irreversibility be primarily from crack-surface oxidation and the hysteresis from dislocation plasticity in surrounding grains.","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"268 1","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142867397","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantifying 3D time-resolved kinematics and kinetics during rapid granular compaction, Part II: Dynamics of heterogeneous pore collapse","authors":"Sohanjit Ghosh, Mohmad M. Thakur, Ryan C. Hurley","doi":"10.1016/j.jmps.2024.106007","DOIUrl":"https://doi.org/10.1016/j.jmps.2024.106007","url":null,"abstract":"Pores in granular materials may occupy significant material volume. Pore-scale dynamics, therefore, strongly influence the macroscopic response of these materials when they are subjected to rapid compaction. In Part I of this series, Ghosh et al. (2024) employed in-situ X-ray imaging coupled with mesoscale finite element modeling to reconstruct the 3D time-resolved kinematics and kinetics of aluminum and soda lime glass powders subjected to rapid compaction. In Part II of this series, presented here, we use the same approach to examine the dynamics of the <ce:italic>pores</ce:italic> and the phenomenon of pore collapse during rapid compaction while also expanding our materials of interest to include Ottawa sand. We find that pore collapse is a highly spatially and temporally heterogeneous process in which pores reach their maximum compacted states across a broad range of timescales dictated by local microstructure, boundary conditions, and grain interactions. Using our data, we assess the validity of common pressure-based (<mml:math altimg=\"si384.svg\" display=\"inline\"><mml:mi>P</mml:mi></mml:math>-<mml:math altimg=\"si260.svg\" display=\"inline\"><mml:mi>α</mml:mi></mml:math>) and strain-based (<mml:math altimg=\"si386.svg\" display=\"inline\"><mml:mi>ϵ</mml:mi></mml:math>-<mml:math altimg=\"si260.svg\" display=\"inline\"><mml:mi>α</mml:mi></mml:math>) porosity evolution models at different length scales, and as a function of grain size, strain rate, and material ductility. We emphasize the importance of boundary conditions when interpreting theoretical porosity evolution models. Overall, our study provides deep new insight into pore collapse and porosity evolution during rapid granular compaction and highlights the importance of accounting for heterogeneous porosity evolution when modeling this process.","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"24 1","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142867398","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimization of constitutive law for objective numerical modeling of knitted fabric","authors":"Agnieszka Tomaszewska, Daniil Reznikov","doi":"10.1016/j.jmps.2024.106017","DOIUrl":"https://doi.org/10.1016/j.jmps.2024.106017","url":null,"abstract":"This paper discusses the problem of macroscopic modeling a knitted technical fabric with the aim to determine a constitutive law for adequately modeling the material response under real-life load. As phenomenological, hyperelastic material laws reveal different parameters due to different test modalities used to identify such parameters, an optimization scheme is proposed to determine an objective solution. The study is conducted for three medical textiles which are differentiated by anisotropy ratios and designed to cover abdominal hernia. The optimization parameters are defined by a constitutive law and the bi-axial test modality. State variables are taken from ex-vivo reference tests on ‘operated’ hernia models subjected to simulated real-life loads generated by post-operative coughs. The objective function is different for isotropic and anisotropic mesh. However, in both cases a numerical model of a mesh placed in the abdominal wall with different variants of the constitutive law is used. The model is constructed according to the finite element method framework. The objective function for isotropic mesh is defined by the variance of reaction forces in mesh fixation points, calculated in the numerical model, while for anisotropic mesh, it is generated by the difference between angles which determine the position of maximal reaction force in the numerical and experimental reference models. Three constitutive laws and five modalities of bi-axial tests are considered. This analysis proves the need for a constitutive model, itself validated by a suitable reference test, instead of an arbitrary decision on bi-axial test modality selected to identify the material law parameters. These conclusions may help to increase the reliability of numerical modeling of operated hernia and increase the effectiveness of hernia treatment.","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"26 1","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142867395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 continuum geometric approach for inverse design of origami structures","authors":"Alon Sardas, Michael Moshe, Cy Maor","doi":"10.1016/j.jmps.2024.106003","DOIUrl":"https://doi.org/10.1016/j.jmps.2024.106003","url":null,"abstract":"Miura-Ori, a celebrated origami pattern that facilitates functionality in matter, has found multiple applications in the field of mechanical metamaterials. Modifications of Miura-Ori pattern can produce curved configurations during folding, thereby enhancing its potential functionalities. Thus, a key challenge in designing generalized Miura-Ori structures is to tailor their folding patterns to achieve desired geometries. In this work, we address this inverse-design problem by developing a new continuum framework for the differential geometry of generalized Miura-Ori. By assuming that the perturbation to the classical Miura-Ori is slowly varying in space, we derive analytical relations between geometrical properties and the perturbation field. These relationships are shown to be invertible, allowing us to design complex curved geometries. Our framework enables porting knowledge, methods and tools from continuum theories of matter and differential geometry to the field of origami metamaterials.","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"78 1","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142867400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced cyclic stability of NiTi shape memory alloy elastocaloric materials with Ni4Ti3 nanoprecipitates: Experiment and phase field modeling","authors":"Bo Xu, Xu Xiao, Qixing Zhang, Chao Yu, Di Song, Qianhua Kan, Chong Wang, Qingyuan Wang, Guozheng Kang","doi":"10.1016/j.jmps.2024.106011","DOIUrl":"https://doi.org/10.1016/j.jmps.2024.106011","url":null,"abstract":"In this work, a NiTi shape memory alloy (SMA) with excellent elastocaloric performance (with an ultrahigh coefficient of performance, i.e., <ce:italic>COP</ce:italic><ce:inf loc=\"post\">mat</ce:inf> of ∼46.5 and an adiabatic temperature change of ∼10.5 K) and good cyclic stability is prepared. A thermo-mechanically coupled and crystal-plasticity-based phase field model including both the descriptions of Ni<ce:inf loc=\"post\">4</ce:inf>Ti<ce:inf loc=\"post\">3</ce:inf> precipitation and martensitic transformation (MT) is newly proposed to reveal the microscopic mechanism behind the cyclic stability of NiTi elastocaloric materials. The dependence of plasticity on the precipitate size is innovatively considered through a Hall-Petch-like relationship between the dislocation slip resistance and the distance between adjacent precipitates, and the pinning effect of dislocation on reverse MT is reflected by introducing an interaction energy. The elastocaloric effect (eCE) and its cyclic evolution of the single-crystal NiTi SMA systems containing Ni<ce:inf loc=\"post\">4</ce:inf>Ti<ce:inf loc=\"post\">3</ce:inf> precipitates with different sizes are simulated. Combined with experimental observations and simulations, new insights are provided on the mechanism behind the enhanced cyclic stability of precipitation strengthened NiTi SMA elastocaloric materials. The results of this work can improve the valuable scheme and theoretical basis for the development of NiTi-based elastocaloric materials with outstanding eCE and good cyclic stability.","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"112 1","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142867399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unified model for adhesive contact between solid surfaces at micro/nano-scale","authors":"Yudong Zhu, Yong Ni, Chenguang Huang, Jilin Yu, Haimin Yao, Zhijun Zheng","doi":"10.1016/j.jmps.2024.106004","DOIUrl":"https://doi.org/10.1016/j.jmps.2024.106004","url":null,"abstract":"Because of the huge specific surface area at the micro/nano scale, inter-surface adhesion and surface effects play a critical role in the behavior of solid-to-solid contact. The inter-surface adhesion originates from the intermolecular traction between two surfaces, while the surface effects, including residual surface stress and surface elasticity, result from the physical discrepancy between the surface atoms and their bulk counterparts. Despite the importance of both effects, theoretically modeling them together is still a challenging open issue because of the nonlinear coupling nature in between. This study is dedicated to the development of a unified theoretical framework with consideration of both inter-surface adhesion and surface effects based on the Gurtin–Murdoch surface elasticity theory. The two effects are integrated into a self-consistent equation concerning surface gaps and interactions, and a novel regularization method is proposed to address the oscillation and singularity of the equation. It is demonstrated that an adhesive contact problem with surface effects can be decomposed into two fundamental issues. One addresses the classical problem without considering residual surface stress or surface elasticity, and the other focuses solely on residual surface stress. Theoretical predictions show that the surface effects suppress or even eliminate the surface deformation and jumping instability during contact, effectively stiffening the solid surfaces. Three types of pull-off force transitions with surface effects are obtained, forming continuous bridges among the rigid (Bradley), soft (JKR), and liquid-like (Young–Dupre) limits. The adhesion transitions considering surface effects in this work are universal, and the existing limits or transitions can be regarded as special cases of this work. Our study provides a further understanding of the adhesive contact between micro/nano solids and may be instructive for practical applications where inter-surface adhesion and surface effects are dominant, such as nanoindentation, micro-electro-mechanical systems, and microelectronics.","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"106 1","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142867479","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterizing dissipated energy density distribution and damage zone in double network hydrogels","authors":"Jiapeng You, Chong Wang, Zhixuan Li, Zishun Liu","doi":"10.1016/j.jmps.2024.106006","DOIUrl":"https://doi.org/10.1016/j.jmps.2024.106006","url":null,"abstract":"The double network hydrogels (DN gels) process high fracture toughness due to their considerable energy dissipation during fracture. To effectively interpret the energy dissipation, it is imperative to conduct a study on the quantitative characterization of the dissipated energy density distribution and the damage zone around the crack tip. In this study, we propose a series of tearing tests on pre-stretched DN gel specimens to quantitatively characterize the dissipated energy density distribution. According to the dissipated energy density distribution, the damage zone of the DN gel during tearing is divided into three parts: hardening zone, yielding zone and pre-yielding zone. The dissipated energy density distribution determines both the feature size and the contribution of these damage zones to the fracture toughness. We reveal that both the dissipated energy density and the feature size of the damage zones significantly influence the fracture toughness. Additionally, this study delves into the effect of the first network's cross-linking degree on the dissipated energy density distribution and damage zone. The dissipated energy density distribution, determined by tearing test, is validated by available experimental results, which show good agreement. This study proposes a quantitatively experimental method to investigate the dissipated energy density distribution and damage zone. It is anticipated that this approach will provide new insights into the energy dissipation mechanism of soft materials.","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"31 1","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142867401","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 tube-based constitutive model of brain tissue with inner pressure","authors":"Wei Liu, Zefeng Yu, Khalil I. Elkhodary, Hanlin Xiao, Shan Tang, Tianfu Guo, Xu Guo","doi":"10.1016/j.jmps.2024.105993","DOIUrl":"https://doi.org/10.1016/j.jmps.2024.105993","url":null,"abstract":"Many blood vessels exist in brain tissue. Their internal blood pressure plays a crucial role in physiological disorders, such as brain edema, stroke, or traumatic brain injury (concussion). Homogenized continuum mechanics-based brain tissue models can provide an attractive approach to rapidly simulate blood-pressure related physiological disorders, and traumatic brain injury. These homogenized models are much easier and faster to apply compared to finite element models that detail the microstructure. This paper thus presents a homogenized constitutive model for brain tissue in which the vascular networks and blood pressure are taken into account. The proposed model is microstructurally motivated and derived, in which the matrix of the brain tissue (gray/white matter) is modeled as hyperelastic material, while the blood vessels with their inner pressure define the microstructure. The proposed constitutive model is implemented in finite element software. Despite the simplicity of the model, we show it predicts strains and stresses comparable to finite element models with detailed microstructural representations under different loading conditions, demonstrating the potential usefulness of the model in rapidly estimating brain injury risk, hematoma formation, as well as brain tissue expansion/shrinkage.","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"40 1","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142867402","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Topological state switches in hard-magnetic meta-structures","authors":"Quan Zhang, Stephan Rudykh","doi":"10.1016/j.jmps.2024.106001","DOIUrl":"https://doi.org/10.1016/j.jmps.2024.106001","url":null,"abstract":"We propose a metamaterial design principle that enables the remote switching of topological states. Dynamic breaking of space-inversion symmetry is achieved through the intricate design of magnetic spring structures within the metamaterial building blocks, whose stiffness can be remotely altered using an external magnetic field. We develop a mathematical model to predict the magnetic field-induced deformation and tangential stiffness of the spring structure with hard-magnetic constituent phase. Building on the predictive model, we explore the necessary conditions – including the magnetization distribution and the direction of the actuating magnetic field – that enable magnetically tunable stiffness. To demonstrate the functionality of topological state switching, we apply the proposed magnetic spring to the topological metamaterial design where a tunable stiffness landscape is essential for reversible topological phase transition. Our mathematical modeling indicates that we can remotely modulate both the dispersion properties and the topological invariants (including Zak phase and winding number) of the underlying bands in the proposed metamaterial system. Finally, we show that this tunable capability extends to controlling topologically protected edge and interface states within the finite-sized metamaterial lattice. Our design strategy for the switching of topological state paves the way for the realization of smart and intelligent metamaterials featuring tunable and active wave dynamics. It also highlights the potential of magneto-mechanical coupling in the design of advanced functional materials.","PeriodicalId":17331,"journal":{"name":"Journal of The Mechanics and Physics of Solids","volume":"218 1","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142788943","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}