【新文速递】2024年12月9日固体力学SCI期刊最新文章

今日更新：International Journal of Solids and Structures 1 篇，Journal of the Mechanics and Physics of Solids 1 篇，Mechanics of Materials 2 篇，International Journal of Plasticity 1 篇International Journal of Solids and StructuresA time-discontinuous elasto-plasticity formalism to simulate instantaneous plastic flow burstsM. Lamari, P. Kerfriden, O.U. Salman, V. Yastrebov, K. Ammar, S. Forestdoi:10.1016/j.ijsolstr.2024.113171一种模拟瞬时塑性流爆的时间不连续弹塑性形式Plastic flow is conventionally treated as continuous in finite element (FE) codes, whether in isotropic, anisotropic plasticity, or crystal plasticity. This approach, derived from continuum mechanics, contradicts the intermittent nature of plasticity at the elementary scale. Understanding crystal plasticity at micro-scale opens the door to new engineering applications, such as microscale machining. In this work, a new approach is proposed to account for the intermittence of plastic deformation while remaining within the framework of continuum mechanics. We introduce a material parameter, the plastic deformation threshold, denoted as Δp_min, corresponding to the plastic deformation carried by the minimal plastic deformation burst within the material. The incremental model is based on the traditional predictor–corrector algorithm to calculate the elastoplastic behavior of a material subjected to any external loading. The model is presented within the framework of small deformations for von Mises plasticity. To highlight the main features of the approach, the plastic strain increment is calculated using normality rule and consistency conditions, and is accepted only if it exceeds Δp_min. To achieve this, a time-discontinuous generalization of the Karush-Kuhn–Tucker (KKT) conditions is proposed. The simulations show that the introduction of the plastic threshold allows for the reproduction of the spatiotemporal intermittence of plastic flow, capturing the self-organization of plastic flow in complex loading scenarios within an FE model.通常在有限元（FE）代码中，塑料流动被认为是连续的，无论是各向同性塑性、各向异性塑性还是晶体塑性。这种方法源于连续介质力学，与在微观尺度上发生的塑性行为的间歇性相矛盾。了解晶体塑性在微观尺度上的行为为新的工程应用打开了大门，例如微尺度加工。在这项工作中，提出了一种新的方法，可以在连续介质力学框架内考虑塑性变形的间歇性。我们引入了一个材料参数，称为最小塑性变形阈值Δp_min，它对应于材料中由最小塑性变形爆发所携带的塑性变形。增量模型基于传统的预测-校正算法来计算材料在任何外部载荷作用下的弹塑性行为。该模型在von Mises塑性理论的小变形框架内进行表述。为了突出该方法的主要特点，采用正常化规则和一致性条件计算塑料应变增量，只有当其超过Δp_min时才被接受。为此，提出了KKT条件的时变连续推广。模拟结果表明，引入塑性阈值可以再现塑料流动的时空间歇性，在FE模型中捕捉复杂加载条件下的塑性流动自组织行为。Journal of the Mechanics and Physics of SolidsCharacterizing Dissipated Energy Density Distribution and Damage Zone in Double Network HydrogelsJiapeng You, Chong Wang, Zhixuan Li, Zishun Liudoi:10.1016/j.jmps.2024.106006双网状水凝胶耗散能密度分布及损伤区表征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.双网状水凝胶（DN凝胶）由于在断裂过程中具有相当大的能量耗散，具有较高的断裂韧性。为了有效地解释能量耗散，有必要对耗散能量密度分布和裂纹尖端周围损伤区进行定量表征研究。在本研究中，我们提出了一系列的撕裂试验预拉伸DN凝胶样品，定量表征耗散能量密度分布。根据耗散能量密度分布，将DN凝胶撕裂过程中的损伤区分为硬化区、屈服区和预屈服区三个部分。耗散能量密度分布决定了这些损伤区域的特征尺寸和对断裂韧性的贡献。结果表明，耗散能密度和损伤区特征尺寸对断裂韧性有显著影响。此外，本研究还探讨了第一网络交联度对耗散能量密度分布和损伤区域的影响。通过撕裂试验确定的耗散能密度分布与已有的实验结果吻合较好。本研究提出了一种定量实验方法来研究耗散能量密度分布和损伤区域。预计该方法将为研究软质材料的能量耗散机制提供新的见解。Mechanics of MaterialsEffects of heat treatment parameters and grain sizes on mechanical response of amorphous/crystalline CuZr compositesMenghan Yin, Mengye Duan, Tao Fu, Jie Wang, Shayuan Weng, Xiang Chen, Xianghe Pengdoi:10.1016/j.mechmat.2024.105233热处理参数和晶粒尺寸对非晶/结晶CuZr复合材料力学响应的影响The amorphous phase proportion in nanocrystalline/amorphous CuZr samples was tailored using heat treatment processes under a fast-dynamic regime by varying temperature and time. It was revealed that using molecular dynamics simulations of tension tests, the samples with a larger fraction of crystalline phase exhibit superior mechanical properties. During tension, a dual-slope phenomenon was observed, driven by grain boundary behaviors and subsequent phase transition in the crystalline phase. The plastic deformation was mainly dominated by slip bands generated from dislocation nucleation in the crystalline phase, rather than embryonic shear bands in the amorphous phase. In contrast, the samples with a higher fraction of amorphous phase exhibit softening, leading to reduced mechanical properties. Plastic deformation in these samples is initiated by shear band nucleation in the amorphous phase, which expands within the amorphous phase and induces the formation of slip bands in the crystalline phase, though deformation remains predominantly governed by shear bands. These results can provide insight into the deformation behavior of nanoscale amorphous/crystalline dual-phase CuZr composites and guidance for the structural optimization of high-strength and high-plasticity amorphous/crystalline composites.采用快速动态热处理工艺，通过改变温度和时间来调整CuZr纳米晶/非晶样品的非晶相比例。通过分子动力学模拟拉伸试验发现，晶相含量较高的试样具有较好的力学性能。在拉伸过程中，观察到由晶界行为和随后的晶相相变驱动的双斜率现象。塑性变形主要以晶态位错形核产生的滑移带为主，而非晶态的胚胎剪切带为主。相反，非晶相含量较高的样品表现出软化，导致力学性能下降。这些样品的塑性变形是由非晶相中的剪切带形核引发的，剪切带在非晶相中扩展，并在晶相中诱发滑移带的形成，尽管变形仍然主要由剪切带控制。这些结果可以为深入了解纳米级非晶/晶双相CuZr复合材料的变形行为，为高强高塑性非晶/晶复合材料的结构优化提供指导。Symmetry breaking and nonreciprocity in nonlinear phononic crystals: Inspiration from atomic interactionsSeyed Mohammad Hosein Abedy Nejad, Mir Masoud Seyyed Fakhrabadidoi:10.1016/j.mechmat.2024.105231非线性声子晶体中的对称性破缺和非互易：来自原子相互作用的启示Symmetry breaking is an emerging trend in metamaterial research. To date, studies have primarily focused on breaking spatial or temporal symmetries through active interactions, leading to promising applications in waveguiding and manipulation. In this paper, we explore symmetry-breaking mechanisms by implementing the Morse-type potential function, resulting in asymmetric stiffness with different behaviors in tension and compression. We further answer whether this type of asymmetric stiffness leads to nonreciprocal behavior. Hence, our research focuses on wave propagation in nonlinear one- and two-dimensional phononic crystals using the Morse potential function. Our methodology then involves extracting dispersion curves using the semi-analytic method of multiple scales and numerical Spectro-spatial analysis. Our findings reveal interesting characteristics, including the formation of a bandgap at lower wave numbers (low-frequency waves), asymmetric wave propagation, and wave amplification. These results hold substantial potential for the design of advanced waveguides and wave filters.对称破缺是超材料研究的一个新兴趋势。迄今为止，研究主要集中在通过主动相互作用打破空间或时间对称性，从而在波导和操纵方面有前景的应用。在本文中，我们通过实现莫尔斯型势函数来探索对称性破坏机制，从而产生具有不同拉伸和压缩行为的非对称刚度。我们进一步回答是否这种类型的不对称刚度导致非互反行为。因此，我们的研究重点是利用莫尔斯势函数研究波在非线性一维和二维声子晶体中的传播。然后，我们的方法包括使用多尺度半解析方法和数值光谱空间分析提取色散曲线。我们的发现揭示了一些有趣的特征，包括在较低波数（低频波）处形成带隙、不对称波传播和波放大。这些结果对设计先进的波导和滤波器具有很大的潜力。International Journal of PlasticityThe interfacial damage of the deformation heterogeneity in the transformation-induced plasticity (TRIP)-assisted duplex stainless steelWenbin Zhang, Miao Jin, Shuo Hao, Mingshuai Huo, Zhenyi Huang, Lei Chen, Wenzhen Xiadoi:10.1016/j.ijplas.2024.104209 相变诱导塑性（TRIP）辅助双相不锈钢中变形不均匀的界面损伤The characteristic of differences in material properties between phases gives rise to significant deformation heterogeneity in dual-phase or multi-phase materials, consequently resulting in complex damage laws. In this study, the microcracks characteristics of transformation-induced plasticity (TRIP)-assisted duplex stainless steel were observed after large deformation (engineering strain up to 55%). It has been determined that microcracks invariably occur at interface locations, including the phase boundary between original austenite and ferrite, the grain boundary of original austenite, and the grain boundary of ferrite. The deformation heterogeneity of various types of interfaces is analyzed by using crystal plasticity finite element method (CPFEM). Deformation degree coordination parameter kl and slip transfer parameter ktf are established, based on the velocity gradient tensor Lp and the slipping rate γ˙ of activated slip system in CPFEM, to analyze the multi-slip heterogeneous deformation behavior of grains on both sides of the interface. A novel interfacial damage model considering the slip transfer parameter ktf is established, which reveals the correlation between deformation heterogeneity and damage mechanism, to provide a criterion for various types of interfacial failure behaviors. The interface damage model based on deformation heterogeneity can stand as an invaluable instrument for exploring the damage behaviors of two-phase or multi-phase materials.材料各相之间物性差异的特性导致了双相或多相材料中显著的变形异质性，从而导致复杂的损伤定律。在这项研究中，观察了变形量较大的（工程应变高达55%）双相不锈钢在TRIP（变形诱导塑性）辅助下的微裂纹特征。结果表明，微裂纹始终发生在界面位置，包括原始奥氏体与铁素体之间的相界面、原始奥氏体的晶界和铁素体的晶界。利用晶体塑性有限元法（CPFEM）分析了各种界面的变形异质性。基于CPFEM中的速度梯度张量Lp和激活滑移系统滑移速率γ˙，建立了变形协调参数kl和滑移转移参数ktf，以分析界面两侧晶粒的多滑移异质变形行为。建立了一种考虑滑移传递参数ktf的界面损伤模型，揭示了变形异质性与损伤机制之间的关联，为各种类型的界面失效行为提供了依据。基于变形异质性的界面损伤模型可作为探索两相或多相材料损伤行为的无价工具。来源：复合材料力学仿真Composites FEM