Ideal strength of nanoscale materials induced by elastic instability
In this study, we investigate ideal strengths of some face-center cubic nanostructures using molecular statics simulations and an elastic stability criterion. The simulation results show that ideal strength depends strongly on loading direction, loading mode (tension or compression), side surface orientation, shape of cross-section, and size. Consequently, nanostructures can exhibit the “smaller is stronger” trend, the “smaller is weaker” trend, and the “size-independent strength plateau” trend. Our semi-analytic model for prediction of ideal strengths of nanostructures is in good agreem...
Source: Mechanics of Materials - November 15, 2019 Category: Materials Science Source Type: research

Electro-thermo-mechanical responses of laminated smart nanocomposite moderately thick plates containing carbon nanotube-A multi-scale modeling
Publication date: Available online 13 November 2019Source: Mechanics of MaterialsAuthor(s): M.J. Mahmoodi, Y. Rajabi, B. KhodaiepourAbstractBending analysis of laminated carbon nanotube (CNT) piezo-nanocomposite moderately thick rectangular plates is presented by a multi-scale approach. Firstly, a unit cell based micromechanical model is developed to obtain the electro-thermo-mechanical behavior of material to transfer to the structure scale. The nanocomposite representative volume element consists of three phases, including CNT, piezoelectric Polyvinylidene Fluoride (PVDF) matrix and an interphase representing the CNT/PVD...
Source: Mechanics of Materials - November 14, 2019 Category: Materials Science Source Type: research

Nanoscale mode-III interface crack in a bimaterial with surface elasticity
Publication date: Available online 11 November 2019Source: Mechanics of MaterialsAuthor(s): Ying Yang, Zhen-Liang Hu, Xian-Fang LiAbstractThis paper studies a mode-III nanocrack at the interface between two bonded dissimilar materials under antiplane shear loading. The classical elasticity incorporating surface elasticity is applied to solve a mixed boundary value problem associated with an anti-plane shear interface crack. The influence of surface elasticity on the crack-tip field for a nanoscale mode-III crack is analyzed. By use of the Fourier transform, the problem is reduced to a set of hypersingular integro-different...
Source: Mechanics of Materials - November 12, 2019 Category: Materials Science Source Type: research

Experimental study of strength properties of SLA resins under low and high strain rates
Publication date: Available online 9 November 2019Source: Mechanics of MaterialsAuthor(s): Danuta Miedzińska, Roman Gieleta, Ewelina MałekAbstractA study of the material properties of resins used for stereolithography rapid prototyping is presented in the paper. The samples were prepared in accordance with producers' guidelines and loaded in two ways: quasi-static and with the use of a Hopkinson bar. Different strain rates were considered in this way. The researched material showed significant differences when responding to the different strain-rate loadings. The presented work will be used in numerical constitutive mode...
Source: Mechanics of Materials - November 11, 2019 Category: Materials Science Source Type: research

Micromechanical Behavior of Ultraviolet-Exposed Polyurea
Publication date: Available online 8 November 2019Source: Mechanics of MaterialsAuthor(s): Atif Mohammed Shaik, Nha Uyen Huynh, George YoussefAbstractThe present study focuses on the microstructural characterization of polyurea after extended UV exposure using a mechanics-based, atomic force microscope (AFM) investigation. Extended exposure to UV radiation resulted in photo-degradation with subsequent photo-oxidation reactions causing an increase in the surface roughness associated with crack nucleation. The crack opening and length were found to increase considerably with the rise in UV exposure duration. The crack growth...
Source: Mechanics of Materials - November 9, 2019 Category: Materials Science Source Type: research

Bioinspired toughness improvement through soft interlayers in mineral reinforced polypropylene
Publication date: Available online 9 November 2019Source: Mechanics of MaterialsAuthor(s): Johannes Wiener, Florian Arbeiter, Abhishek Tiwari, Otmar Kolednik, Gerald PinterAbstractThe effects of soft, polymeric interlayers on a brittle, mineral reinforced polymer matrix are investigated. Interlayers made of a standard polypropylene (PP) and a soft type of PP are introduced into matrix materials of either highly or moderately mineral particle reinforced PP. Single edge notch bending experiments are performed to characterize the fracture toughness of these composites. The experimental J-integral Jexp is used to describe the ...
Source: Mechanics of Materials - November 9, 2019 Category: Materials Science Source Type: research

Towards exploiting inelastic design for Inconel 625 under short-term cyclic loading at 600∘C
Publication date: January 2020Source: Mechanics of Materials, Volume 140Author(s): I. Soner Cinoglu, Ali Charbal, Natasha VermaakAbstractMany industries rely on the Inconel 625 alloy to serve under thermomechanical operating conditions. Understanding the macroscopic cyclic inelastic behavior of this material is vital for accurate assessment of its load-carrying capacity at elevated temperatures. In this work, a uniaxial experimental program at 600∘C is conducted to demonstrate designing for cyclic elastoplastic behavior (shakedown) as opposed to more restrictive first-yield, while still avoiding ratchetting or alternatin...
Source: Mechanics of Materials - November 9, 2019 Category: Materials Science Source Type: research

Energy dissipation in pH-sensitive hydrogels subjected to large amplitude oscillatory shear
Publication date: January 2020Source: Mechanics of Materials, Volume 140Author(s): Pranitha Prabhakaran, Chandler C. BenjaminAbstractStimuli-responsive hydrogels belong to a class of shape-memory elastomers that have gained immense popularity due to their applications in the fields of drug delivery, tissue engineering, implants, bio-sensors, and many more. The pH-responsive hydrogels 2-hydroxyethyl methacrylate (2-dimethylamino) ethyl methacrylate (HEMA-DMAEMA) and 2-hydroxyethyl methacrylate acrylic acid (HEMA-AA) exhibit swelling behavior in response to changes in pH. The present study characterizes the energy dissipatio...
Source: Mechanics of Materials - November 9, 2019 Category: Materials Science Source Type: research

Vibration analysis of tapered circular poroelastic plates with radially graded porosity using pseudo-spectral method
Publication date: Available online 6 November 2019Source: Mechanics of MaterialsAuthor(s): S.K. Jalali, M. HeshmatiAbstractAttractive properties of Functionally Graded (FG) porous materials (porous materials with functionally graded porosity) are of special interest to engineers and researchers to design and develop improved mechanical properties in a wide range of aerospace, biomedical, civil, mechanical and vehicle engineering applications. This paper aims to use First-order Shear Deformation Theory (FSDT) and investigate free vibration of tapered circular porous plates with graded open-cell porosity as a new lightweight...
Source: Mechanics of Materials - November 8, 2019 Category: Materials Science Source Type: research

On the double transition in the failure mode of polycarbonate
Publication date: Available online 7 November 2019Source: Mechanics of MaterialsAuthor(s): J. Aranda-Ruiz, K. Ravi-Chandar, J.A. LoyaAbstractIn the present work, the transition in the mode of failure from brittle to ductile, observed in certain polymeric materials, is explored both experimentally and numerically, focusing on polycarbonate, a polymer of wide industrial use. The limit between both behaviours depends on several intrinsic factors, such as temperature and deformation rate, and extrinsic factors such as notch radius and specimen thickness. The parameters that have been explored in this work are the thickness of ...
Source: Mechanics of Materials - November 8, 2019 Category: Materials Science Source Type: research

Energy Dissipation in pH-sensitive hydrogels subjected to large amplitude oscillatory shear.
Publication date: Available online 4 November 2019Source: Mechanics of MaterialsAuthor(s): Pranitha Prabhakaran, Chandler BenjaminAbstractStimuli-responsive hydrogels belong to a class of shape-memory elastomers that have gained immense popularity due to their applications in the fields of drug delivery, tissue engineering, implants, bio-sensors, and many more. The pH-responsive hydrogels 2-hydroxyethyl methacrylate (2-dimethylamino) ethyl methacrylate (HEMA-DMAEMA) and 2-hydroxyethyl methacrylate acrylic acid (HEMA-AA) exhibit swelling behavior in response to changes in pH. The present study characterizes the energy dissi...
Source: Mechanics of Materials - November 5, 2019 Category: Materials Science Source Type: research

Editorial Board
Publication date: December 2019Source: Mechanics of Materials, Volume 139Author(s): (Source: Mechanics of Materials)
Source: Mechanics of Materials - November 5, 2019 Category: Materials Science Source Type: research

A Micromechanics-Based Constitutive Model for Linear Viscoelastic Particle-Reinforced Composites
Publication date: Available online 1 November 2019Source: Mechanics of MaterialsAuthor(s): Yang Chen, Pingping Yang, Yexin Zhou, Zaoyang Guo, Leiting Dong, Esteban P. BussoAbstractIn this paper, a novel micromechanics-based constitutive model is proposed for linear viscoelastic particle-reinforced composites based on a homogenization approach in the time domain. After decomposing the deformation into its volumetric and deviatoric parts, the long-term responses of the constituents are utilized to formulate the constitutive equations of the composites. The strain energy contributions of the constituents are computed from mic...
Source: Mechanics of Materials - November 2, 2019 Category: Materials Science Source Type: research

Seismic attenuation and dispersion in a cracked porous medium: An effective medium model based on poroelastic linear slip conditions
Publication date: Available online 1 November 2019Source: Mechanics of MaterialsAuthor(s): Yongjia Song, Hengshan Hu, Bo HanAbstractMechanical and hydraulic properties of a crack can significantly affect seismic wave propagation. To explore these effects, we developed an effective medium model that describes the P-wave dispersion and attenuation in inhomogeneous porous media containing a distribution of aligned cracks. Although there are numerous theoretical models for quantifying the seismic dispersion and attenuation, some of them are restricted to low frequencies at which only effects of the wave-induced fluid flow (WIF...
Source: Mechanics of Materials - November 2, 2019 Category: Materials Science Source Type: research

Out-of-plane mechanical behaviors of a side hierarchical honeycomb
Publication date: Available online 1 November 2019Source: Mechanics of MaterialsAuthor(s): Yong Zhang, Tengteng Chen, Xiang Xu, Zhongwei HuAbstractHierarchical honeycombs have been extensively used as protective devices due to their superior mechanical performance. In this paper, a novel side hierarchical triangular honeycomb (SHTH) constructed by sequentially arranging a certain number of similar subtriangles on the geometrical side of an ordinary triangular honeycomb (OTH) is proposed to enhance structural mechanical performance. Experimental specimens and finite element models of SHTHs are developed to explore their mec...
Source: Mechanics of Materials - November 2, 2019 Category: Materials Science Source Type: research

The parametric HFGMC micromechanical model for soft UHMWPE laminated composites
Publication date: Available online 31 October 2019Source: Mechanics of MaterialsAuthor(s): Ido Meshi, Aviad Levi-Sasson, Uri Breiman, Rami Haj-AliAbstractThe 3D parametric High-Fidelity-Generalized-Method-of-Cells (HFGMC) micromechanical model was used to predict the mechanical tensile behavior of ultra-high-molecular-weight-polyethylene (UHMWPE) cross-ply laminated composite (Dyneema®). The composite microstructure was obtained from optical microscope images and was digitized using CAD software. Two configurations of 3D representative-volume-elements (RVE)s were constructed and analyzed to demonstrate t...
Source: Mechanics of Materials - November 2, 2019 Category: Materials Science Source Type: research

Prediction of effective elastic properties of a polypropylene component by an enhanced multiscale simulation of the injection molding process
Publication date: Available online 31 October 2019Source: Mechanics of MaterialsAuthor(s): Gottfried Laschet, Hamed Nokhostin, Simon Koch, Marc Meunier, Christian HopmannAbstractIn the injection molding process of semi-crystalline polymers, the melt undergoes a complex deformation and cooling history which results in an inhomogeneous distribution of spherulites in the component. To evaluate these inhomogeneities in an isotactic polypropylene (α-iPP) part, an integrated multi-scale simulation approach has been developed in Laschet et al.. (2017a). This approach combines a macroscale mold filling and heat transfer anal...
Source: Mechanics of Materials - November 2, 2019 Category: Materials Science Source Type: research

Thermally-activated hardening recovery of thermo-elasto-plastic metals during annealing: constitutive modeling for the simulation of welding process
Publication date: Available online 1 November 2019Source: Mechanics of MaterialsAuthor(s): L. Mouelle, F. Praud, G. Chatzigeorgiou, F. Meraghni, J. Serri, E. FleuryAbstractIn this paper, a new thermodynamically-consistent modeling approach, dedicated to welding applications, is presented to describe the phenomenon of hardening recovery in metals during annealing. The constitutive equations are based on a classical thermo-elasto-plastic formulation, which is enhanced by a new recovery variable counterbalancing the effect of the hardening through a temperature-dependent evolution law. The identification of the model paramete...
Source: Mechanics of Materials - November 2, 2019 Category: Materials Science Source Type: research

On the relative accuracy of power law analyses for uniaxial low stress steady state high homologous temperature deformation
Publication date: Available online 28 October 2019Source: Mechanics of MaterialsAuthor(s): A. Arsath Abbasali, S. Balasivanandha Prabu, K.A. PadmanabhanAbstractIf the mathematical operations are correct, uniaxial low stress, steady state high homologous temperature creep and steady state structural Superplasticity phenomena can be well described by a ‘power law’ that relates the applied stress to the strain rate of deformation (Padmanabhan et al., 2015). Isothermal dislocation creep, which exhibits no grain size dependence, displays a linear log strain rate – log stress relationship till there is a change...
Source: Mechanics of Materials - October 30, 2019 Category: Materials Science Source Type: research

Fractional creep and relaxation models of viscoelastic materials via a non-Newtonian time-varying viscosity: physical interpretation
Publication date: Available online 25 October 2019Source: Mechanics of MaterialsAuthor(s): Xianglong Su, Wenxiang Xu, Wen Chen, Haixia YangAbstractFractional viscoelastic models have been confirmed to achieve good agreement with experimental data using only a few parameters, in contrast to the classical viscoelastic models in previous studies. With an increasing number of applications, the physical meaning of fractional viscoelastic models has been attracting more attention. This work establishes an equivalent viscoelasticity (including creep and relaxation) between the fractional Maxwell model and the time-varying viscosi...
Source: Mechanics of Materials - October 27, 2019 Category: Materials Science Source Type: research

Damage mechanism and dynamic constitutive model of frozen soil under uniaxial impact loading
Publication date: Available online 25 October 2019Source: Mechanics of MaterialsAuthor(s): Fulai Zhang, Zhiwu Zhu, Tiantian Fu, Jinxuan JiaAbstractThe dynamic mechanical properties of frozen soil at different temperatures and high strain rates were tested using a split Hopkinson pressure bar (SHPB), and the variation of the wave impedance of the frozen soil was analyzed. Viscoelastic theory confirmed that an increase in the wave impedance in frozen soil over short times is the result of unfrozen water relaxation. Unfrozen water is an important factor that increases the peak stress of frozen soil under impact loading. Based...
Source: Mechanics of Materials - October 27, 2019 Category: Materials Science Source Type: research

Studying hydrogen effect on the core structure and mobility of dislocation in nickel by atomistically-informed generalized Peierls-Nabarro model
Publication date: Available online 24 October 2019Source: Mechanics of MaterialsAuthor(s): Zhouqi Zheng, Shuang Liang, Yaxin Zhu, Minsheng Huang, Zhenhuan LiAbstractHydrogen (H) atoms in the metallic crystalline lattice interact with the pre-existing dislocations and then remarkably affect the plastic deformation of metals. Thereby quantitatively characterizing the H-dislocation interaction is of great importance for understanding H-induced plasticity and failure. Most of the previous studies have focused on the long-range interaction between hydrogen and dislocation, but rarely considered the short-range interaction, espe...
Source: Mechanics of Materials - October 25, 2019 Category: Materials Science Source Type: research

Towards exploiting inelastic design for Inconel 625 under short-term cyclic loading at 600oC
Publication date: Available online 24 October 2019Source: Mechanics of MaterialsAuthor(s): I. Soner Cinoglu, Ali Charbal, Natasha VermaakAbstractMany industries rely on the Inconel 625 alloy to serve under thermomechanical operating conditions. Understanding the macroscopic cyclic inelastic behavior of this material is vital for accurate assessment of its load-carrying capacity at elevated temperatures. In this work, a uniaxial experimental program at 600oC is conducted to demonstrate designing for cyclic elastoplastic behavior (shakedown) as opposed to more restrictive first-yield, while still avoiding ratchetting or alte...
Source: Mechanics of Materials - October 25, 2019 Category: Materials Science Source Type: research

Dynamic compression behaviors of concrete under true triaxial confinement: An experimental technique
Publication date: Available online 24 October 2019Source: Mechanics of MaterialsAuthor(s): Songlin Xu, Junfang Shan, Lei Zhang, Lijiang Zhou, Guangfa Gao, Shisheng Hu, Pengfei WangAbstractA dynamic testing system for concrete-like material under static triaxial confinements is developed in the present article. The cubic specimen with length 50 mm is constrained by six steel square bars. The static triaxial confinements are applied on the specimen through six steel bars that independently servo-controlled by three hydraulic cylinders. A striker is then launched to impact the incident bar along the x-axis. The dynamic respon...
Source: Mechanics of Materials - October 25, 2019 Category: Materials Science Source Type: research

A hierarchical hyperelastic-based approach for multi-scale analysis of defective nano-materials
Publication date: Available online 21 October 2019Source: Mechanics of MaterialsAuthor(s): M. Jahanshahi, H. Ahmadi, A.R. KhoeiAbstractIn this paper, a continuum–atomistic multi-scale method is presented in modeling the nonlinear behavior of nano-materials under large deformation. In order to identify an appropriate strain energy function for crystalline nano-structures with different percentages of spherical voids, the hyperelastic method is employed for specimen whose behavior is determined based on the molecular dynamics analyses. In the atomistic level, the EAM many-body potential is employed to model the interac...
Source: Mechanics of Materials - October 22, 2019 Category: Materials Science Source Type: research

Numerical investigation of the temperature dependence of dynamic yield stress of typical BCC metals under shock loading with a dislocation-based constitutive model
Publication date: Available online 20 October 2019Source: Mechanics of MaterialsAuthor(s): Songlin Yao, Xiaoyang Pei, Zhanli Liu, Jidong Yu, Yuying Yu, Qiang WuAbstractInterpretation of the temperature dependence of the dynamic yield stress of shock-loaded metals has recently become a critical problem in shock wave physics. However, the temperature dependence of the dynamic yield stress of BCC metals is rarely investigated owing to the lack of an accurate description of the constitutive behavior of BCC metals subjected to high strain rate and high temperature. To unravel the underlying mechanism of the dynamic yield stress...
Source: Mechanics of Materials - October 21, 2019 Category: Materials Science Source Type: research

The Effect of Loading Duration on Damage Initiation in High-Strength Concrete
This study investigates the failure process in high-strength concrete (HSC) specimens under uniaxial compression loading. This is accomplished through the use of a modified Kolsky compression bar to apply controlled and repeatable mechanical loading in combination with the non-destructive observation capability of high-resolution X-Ray Computed-Microtomography (micro-CT). The evolution of specimen damage morphology is observed as a result of intermittent short-duration uniaxial stress loadings. Experimental results show that HSC specimens are capable of supporting the applied stress above their quasi-static failure strengt...
Source: Mechanics of Materials - October 19, 2019 Category: Materials Science Source Type: research

Interplay of various fracture mechanisms in bio-inspired staggered structure
Publication date: Available online 18 October 2019Source: Mechanics of MaterialsAuthor(s): Avtar Singh, Taranjeet Singh Sandhu, Siladitya PalAbstractStaggered structures have materialized to be an exquisite configuration possessing stiffness, strength and toughness, simultaneously. Various biocomposites such as nacre, teeth and bone display aforesaid properties consisting of hard phase in the form of platelets embedded in soft matrix. Platelet fracture, matrix fracture, and platelet-matrix interface debonding are found to be primary mechanisms behind emergent mechanical behaviors. However, the interaction of these fracture...
Source: Mechanics of Materials - October 19, 2019 Category: Materials Science Source Type: research

Numerical study of static and dynamic fracture behaviours of neat epoxy resin
Publication date: Available online 16 October 2019Source: Mechanics of MaterialsAuthor(s): Dayou Ma, Ali Esmaeili, Andrea Manes, Claudio Sbarufatti, Alberto Jiménez-Suárez, Marco Giglio, A.M.S. HamoudaAbstractIn the present study, a numerical model was built using LS-DYNA® to investigate the static and dynamic fracture behaviours of neat epoxy. Fracture and Izod tests were conducted experimentally for validation. The applicability of different numerical methods, i.e., finite element method and meshfree methods (element-free Galerkin, and smoothed particle Galerkin), was investigated considering different ...
Source: Mechanics of Materials - October 19, 2019 Category: Materials Science Source Type: research

Homogenization accounting for size effects in particulate composites due to general interfaces
Publication date: Available online 15 October 2019Source: Mechanics of MaterialsAuthor(s): Soheil Firooz, George Chatzigeorgiou, Fodil Meraghni, Ali JaviliAbstractTwo analytical approaches are developed to determine the overall size-dependent response of composites embedding general interfaces. The first approach extends the composite sphere assemblage (CSA) approach and the generalized self-consistent method (GSCM) to account for the general interface model resulting in new bounds and estimates on the macroscopic properties of particulate composites. In the second approach, we develop an interface-enhanced Mori–Tana...
Source: Mechanics of Materials - October 16, 2019 Category: Materials Science Source Type: research

Interaction of a straight screw dislocation with a circular cylindrical inhomogeneity in the context of second strain gradient theory of elasticity
Publication date: Available online 15 October 2019Source: Mechanics of MaterialsAuthor(s): M.R. Delfani, P. Forghani-AraniAbstractIn the context of Mindlin’s second strain gradient theory of elasticity, this paper presents an analysis of the elastic state of an infinite isotropic medium that contains a straight screw dislocation in the vicinity of a circular cylindrical inhomogeneity. For determination of the interaction fields of such an inhomogeneity–dislocation ensemble, first the dislocation is described by a proper eigenstrain field. Then, by applying a sufficient number of continuity conditions across the...
Source: Mechanics of Materials - October 16, 2019 Category: Materials Science Source Type: research

A numerical study of the indentation mechanics of shape memory alloys in different temperature regimes
The objective of this work is to investigate the effect of temperature on the mechanics of spherical indentation of SMAs as manifested through stress induced martensite transformation (SIMT) and plastic yielding. To this end, finite element simulations of spherical indentation response of Ni-Ti based SMAs are carried out using a constitutive model that incorporates the combined effects of superelasticity and plasticity. A range of temperatures from well below to above the austenite finish temperature Af is considered. It is found that while SIMT is the governing deformation mode during indentation at temperatures below Af,...
Source: Mechanics of Materials - October 15, 2019 Category: Materials Science Source Type: research

Comprehensive beam models for buckling and bending behavior of simple nanobeam based on nonlocal strain gradient theory and surface effects
Publication date: Available online 15 October 2019Source: Mechanics of MaterialsAuthor(s): Mohammad Hashemian, Shahin Foroutan, Davood ToghraieAbstractIn this paper, bending and buckling behavior of nanobeam utilizing different beam theories including Timoshenko, Euler-Bernoulli, and higher-order beam theories are developed to investigate. The governing equations are derived based on nonlocal strain gradient theory incorporating surface effects. In order to solve the governing equation by a numerical solution, the Navier's method is utilized, and the simply supported boundary condition is imposed. Critical buckling load an...
Source: Mechanics of Materials - October 15, 2019 Category: Materials Science Source Type: research

Hierarchical-microstructure based modeling for plastic deformation of partial recrystallized copper
Publication date: Available online 11 October 2019Source: Mechanics of MaterialsAuthor(s): Yao Liu, Songlin Cai, Mingyao Su, Yunjiang Wang, Dai LanhongAbstractHierarchical microstructure in partial recrystallized materials can simultaneously improve the strength and ductility of metallic materials. Modeling the mechanical behavior of partial recrystallized materials helps to process materials with superior combination of ductility and strength. Here, using experimental characterization, cellular automation (CA) and finite element method, hierarchical-microstructure based modeling was proposed to simulate the tensile deform...
Source: Mechanics of Materials - October 12, 2019 Category: Materials Science Source Type: research

Modeling dislocations with arbitrary character angle in face-centered cubic transition metals using the phase-field dislocation dynamics method with full anisotropic elasticity
In this study, we present a phase-field dislocation dynamics (PFDD) method that includes full anisotropic elasticity. We apply it to calculate the equilibrium core structures of dislocations with arbitrary character angle in eight face-centered cubic transition metals. The calculations investigate the effects of the gradient energy density in the total energy density and the choice of the averaging scheme to determine the isotropic equivalent elastic moduli (i.e., Voigt, Reuss and Hill). We show that the addition of the gradient energy term increases the intrinsic stacking fault (ISF) widths for the edge and screw dislocat...
Source: Mechanics of Materials - October 12, 2019 Category: Materials Science Source Type: research

A ductile fracture model based on continuum thermodynamics and damage
Publication date: Available online 10 October 2019Source: Mechanics of MaterialsAuthor(s): Razanica S., Larsson R., Josefson B.L.AbstractThe paper presents an approach to ductile failure modeling derived based on continuum thermodynamics and damage. A continuum damage enhanced formulation of the effective material is used to describe the degradation of the response. From the thermo-mechanically motivated dissipation rate, a novel damage driving energy that involves both stored energy and dissipative contributions due to inelasticity is presented. This damage driving energy is combined with a damage threshold that controls ...
Source: Mechanics of Materials - October 12, 2019 Category: Materials Science Source Type: research

Evaluation of carbon fiber and p-aramid composite for industrial helmet using simple cross-ply for protecting human heads
In this study, to improve the safety performance of industrial helmets, an epoxy resin was used as a matrix to produce a p-aramid/carbon fiber composite as a simple cross-ply, and compared to p-aramid fiber-reinforced composites, carbon fiber-reinforced composites, and ABS plastic. The specimens were prepared by the compression molding method, and their mechanical properties including the impact strength, tensile strength, flexural strength, and inter-laminar shear strength along with heat resistance properties were observed via thermogravimetric analysis. (Source: Mechanics of Materials)
Source: Mechanics of Materials - October 10, 2019 Category: Materials Science Source Type: research

Novel theories on magneto-electro-elastic ellipsoidal multi-inclusions and inhomogeneities and associated impotent fields
Publication date: Available online 9 October 2019Source: Mechanics of MaterialsAuthor(s): E. Rashidinejad, H.M. ShodjaAbstractThe exact nature of the induced coupled-fields of anisotropic magneto-electro-elastic ellipsoidal inclusions, multi-inclusions, and inhomogeneities with non-uniform eigenfields under polynomial magneto-electro-elastic far-field loadings is of particular interest. For the sake of prediction of the induced coupled-fields of magneto-electro-elastic multi-inclusions due to piecewise polynomial generalized eigenfields several theorems and corollaries are stated and proved. Some classes of impotent genera...
Source: Mechanics of Materials - October 10, 2019 Category: Materials Science Source Type: research

Effects of crystalline orientation, twin boundary and stacking fault on the crack-tip behavior of a Mode I crack in nanocrystalline titanium
Publication date: Available online 9 October 2019Source: Mechanics of MaterialsAuthor(s): Jun Cai, Changwen Mi, Qiong Deng, Chenyi ZhengAbstractIn this work, molecular dynamics simulation and linear elastic fracture mechanics were employed to analyze the crack-tip behavior of a Mode I crack in nanocrystalline titanium. The effects of crystalline orientation, twin boundary and stacking fault on crack propagation were taken into account. Simulation results demonstrate that the crack-tip behavior and thus the crack propagation mode strongly depend on crystalline orientations and plane defects. Cracks lying on the hexagonal cl...
Source: Mechanics of Materials - October 10, 2019 Category: Materials Science Source Type: research

Enforcing shaping of thin gel sheets by anisotropic swelling
Publication date: Available online 7 October 2019Source: Mechanics of MaterialsAuthor(s): Daniele Battista, Michele Curatolo, Paola NardinocchiAbstractThis paper investigates swelling-induced shaping in bilayer thin plates. Sphere-like and nearly developable shapes are realized and the ability to control a specific shaping, shifting from one shape to another, under anisotropic swelling is investigated. It is shown that reinforcing fibers can be crucial in controlling shaping under swelling and dramatically affect the characteristics of the final shapes. (Source: Mechanics of Materials)
Source: Mechanics of Materials - October 9, 2019 Category: Materials Science Source Type: research

Thermomechanical Characterization of Alclad AA2024-T3 Aluminum Alloy using Split Hopkinson Tension Bar
Publication date: Available online 4 October 2019Source: Mechanics of MaterialsAuthor(s): Sahand Pourhassan Shamchi, Francisco J.M. Queirós de Melo, Paulo J. Tavares, Pedro M.G.P. MoreiraAbstractThis work covers the mechanical behavior of Alclad AA2024-T3 aluminum alloy subjected to strain rates ranging from 10−3 s−1 to 1150s−1 and temperatures from 24°C up to 250°C for dynamic and up to 350°C for quasi-static experiments. Dynamic tension tests were conducted using split Hopkinson tension bar (SHTB) apparatus. In-situ strain mapping using Digital Image Correlation (DIC) technique has be...
Source: Mechanics of Materials - October 6, 2019 Category: Materials Science Source Type: research

Manufacturing of 3D-metallic electromagnetic metamaterials for feedhorns used in radioastronomy and satellite communications
Publication date: Available online 2 October 2019Source: Mechanics of MaterialsAuthor(s): Javier De Miguel-Hernández, Roger J. Hoyland, Darío Sosa-Cabrera, Sebastiaan Deviaene, Pablo A. Fuerte-Rodríguez, Eduardo D. González-Carretero, Afrodisio Vega-MorenoAbstractThe electromagnetic metamaterials at microwaves frequencies are well established in industrial applications nowadays. Recent research has shown that a specific kind of metallic metamaterial can contribute to improve the performance of the microwave feedhorns used in radioastronomy and satellite telecommunications. In this article, we th...
Source: Mechanics of Materials - October 3, 2019 Category: Materials Science Source Type: research

Editorial Board
Publication date: November 2019Source: Mechanics of Materials, Volume 138Author(s): (Source: Mechanics of Materials)
Source: Mechanics of Materials - September 30, 2019 Category: Materials Science Source Type: research

Temperature-dependent elastic modulus model for metallic bulk materials
In this study, a new temperature-dependent elastic modulus model without fitting parameters for metallic bulk materials is developed. The model is capable of predicting the Young's modulus, elastic constant, and shear modulus at different temperatures. Good agreement is obtained between values predicted by the model and available experimental data of body-centered-cubic metals, faced-centered-cubic metals, wrought superalloys, and cast superalloys. The inherent relationships between temperature-dependent elastic modulus, coefficient of expansion, heat capacity (or Debye temperature), and melting point of metallic materials...
Source: Mechanics of Materials - September 29, 2019 Category: Materials Science Source Type: research

Damage evolution and plasticity development of concrete materials subjected to freeze-thaw during the load process
Publication date: Available online 27 September 2019Source: Mechanics of MaterialsAuthor(s): Ming Sun, Dabo Xin, Chaoying ZouAbstractFreeze-thaw has a severe degradation effect on concrete materials, especially in cold regions. The damage evolution and plasticity development of concrete materials subjected to freeze-thaw during the load process are essential to improve the frost durability of concrete structures. In this paper, a cohesion reduction parameter is proposed to improve the accuracy of previous damage constitutive models for concrete materials. The value of parameter is determined by a theoretical proof, which i...
Source: Mechanics of Materials - September 29, 2019 Category: Materials Science Source Type: research

A universal modified MRT LBM for common non-Newtonian fluids and their applications
Publication date: Available online 26 September 2019Source: Mechanics of MaterialsAuthor(s): Wu Weiwei, Sun Shouli, Wang Zhouzhou, Ding ShuangAbstractAs a mesoscopic computational method, the lattice Boltzmann method (LBM) has been widely applied in engineering physics areas. When it is used for non-Newtonian fluids, the greatest challenges are instability and poor accuracy. To solve the problem, an idea is introduced based on the multi-relaxation-time lattice Boltzmann method (MRT LBM), which is applicable to common non-Newtonian fluids. The non-Newtonian effect is considered a special external force term, whereas the spe...
Source: Mechanics of Materials - September 28, 2019 Category: Materials Science Source Type: research

A thermodynamic constitutive model with temperature effect based on particle rearrangement for geomaterials
Publication date: Available online 24 September 2019Source: Mechanics of MaterialsAuthor(s): Bing Bai, Guang-chang Yang, Tao Li, Gao-sheng YangAbstractA thermo-hydro-mechanical constitutive model is developed for geomaterials based on the tenet of particle rearrangement in porous granular materials undergoing thermodynamic processes. In this model, the concepts of particle entropy, particle temperature, migration coefficient and potential energy density function are introduced. The effects of temperature and saturation variation on energy dissipation and the soil–water characteristic curve of the geomaterials are als...
Source: Mechanics of Materials - September 26, 2019 Category: Materials Science Source Type: research

Homogenization and Localization of Imperfectly Bonded Periodic Fiber-Reinforced Composites
Publication date: Available online 24 September 2019Source: Mechanics of MaterialsAuthor(s): Guannan Wang, Wenqiong Tu, Qiang ChenAbstractAn elasticity-based micromechanics model is derived analytically to investigate the homogenized and localized responses of unidirectional composites with imperfect interfaces. To mimic the perturbation of the inclusion positioning caused by the consolidation process, an arbitrarily parallelogram-shaped repeating unit cell (RUC) is developed with periodic boundary conditions. Different from the finite-element/volume approaches which solve a boundary-value problem in the discretized domain...
Source: Mechanics of Materials - September 26, 2019 Category: Materials Science Source Type: research

Numerical simulations of the damage evolution for plastic-bonded explosives subjected to complex stress states
Publication date: Available online 18 September 2019Source: Mechanics of MaterialsAuthor(s): Ming Liu, Xicheng Huang, Yanqing Wu, Chengjun Chen, Fenglei HuangAbstractA viscoelastic–viscoplastic damage model is developed to describe the inelastic stress–strain responses and fracture processes of plastic-bonded explosives (PBXs) under complex stress states. This model improves the viscoelastic cracking constitutive model called ViscoSCRAM in two respects. (1) The growth rate factor of pressure-dependent tensile damage is incorporated into microcrack evolution equations, and the tension–compression asymmetry...
Source: Mechanics of Materials - September 20, 2019 Category: Materials Science Source Type: research

Electrochemical viscoelastic modeling to predict quasi-static and dynamic response of IPMC actuators
Publication date: November 2019Source: Mechanics of Materials, Volume 138Author(s): Sajad SamPour, Hossein Moeinkhah, Hossein RahmaniAbstractA nonlinear dynamic viscoelastic model of an ionic polymer metal composite (IPMC) actuator is presented based on the viscoelastic constitutive equations and an energy-based variational approach to acquire dynamic and quasi-static response. For this purpose, the equation of motion of an IPMC actuator is obtained by considering the actuator as a cantilever viscoelastic beam and utlizing continuum mechanic relations, Euler-Bernoulli beam theory, Hamilton's principle, and electrochemical ...
Source: Mechanics of Materials - September 14, 2019 Category: Materials Science Source Type: research