【新文速递】2024年2月28日固体力学SCI期刊最新文章
今日更新：International Journal of Solids and Structures 1 篇，International Journal of Plasticity 1 篇，Thin-Walled Structures 1 篇International Journal of Solids and StructuresIsotropic Elasticity of Dilatational Conical Inclusion.AN analytical APPROACHNguyen Van Tuyen, A.L Kolesnikova, A.E. Romanovdoi:10.1016/j.ijsolstr.2024.112735 扩张圆锥包容体的各向同性弹性--一种分析方法In this article, the analytical solution for the isotropic elasticity problem for the cone-shaped inclusion with dilatational eigenstrain in an infinite medium is given. The conical inclusion is modeled by dilatational infinitesimally thin circular disks distributed continuously along the cone z-axis with the radii of the disks being proportional to z-coordinate. The displacements, strains, and stresses of the conical inclusion are given in spherical coordinates with the origin in the cone-apex in the form of the series with Legendre polynomials. The maps of the displacements and the stresses are presented. A comparison of the displacements of the conical inclusion with the displacements of the finite cylindrical and hemispherical inclusions is provided. It is also shown, as expected, that the energy of the dilatational inclusion does not depend on its shape. In Discussion section, the specific features of an “hourglass” dipole inclusion consisting of two conical inclusions with different sign eigenstrains are demonstrated.本文给出了在无限介质中具有扩张特征应变的锥形包含体的各向同性弹性问题的解析解。锥形内含物由沿锥体 Z 轴连续分布的扩张性无限薄圆盘建模，圆盘半径与 Z 坐标成正比。锥形内含物的位移、应变和应力以球面坐标给出，原点位于锥顶，采用 Legendre 多项式的序列形式。并给出了位移和应力的分布图。将锥形内含物的位移与有限圆柱形和半球形内含物的位移进行了比较。结果还表明，正如预期的那样，膨胀夹杂物的能量并不取决于其形状。在讨论部分，演示了由两个具有不同符号特征应变的圆锥内含物组成的 "沙漏 "偶极内含物的具体特征。International Journal of PlasticityDeciphering non-elastic deformation in amorphous alloy: Simultaneous aging-induced ordering and rejuvenation-induced disorderingQ. Hao, G.J. Lyu, E. Pineda, J.M. Pelletier, Y.J. Wang, Y. Yang, J.C. Qiaodoi:10.1016/j.ijplas.2024.103926 解密非晶合金的非弹性变形：同时发生的老化诱导有序化和再生诱导无序化The mechanical and physical properties of amorphous alloys depend on their time, temperature, and stress history. Due to their out-of-thermodynamic-equilibrium nature, describing the nonelastic deformation while considering the evolution of the structural state poses a significant challenge. We address this challenge by incorporating a parameter for structural state changes into a conventional deformation theory. This allows us to account for aging-induced ordering and deformation-induced disordering in the description of the mechanical deformation. In the apparent elastic regime (small strain), aging dominates while disorder caused by deformation can be disregarded. In this context, we have also made modifications to the widely used stretched exponential function, incorporating in situ aging during deformation. This modification successfully describes the stress relaxation behavior under small deformation conditions and provides insights into parameter evolution in this process. Under large deformation conditions, both aging and deformation induced rejuvenation effects on the structural state must be considered simultaneously. By analyzing the evolution of defect concentration during this process, we describe relevant experimental results within the framework of the free volume theory, effectively separating the contributions of aging and rejuvenation to the structural state during the deformation process.非晶合金的机械和物理特性取决于其时间、温度和应力历史。由于非热力学平衡性质，在考虑结构状态演变的同时描述非弹性变形是一项重大挑战。为了应对这一挑战，我们在传统的变形理论中加入了结构状态变化参数。这使我们能够在描述机械变形时考虑老化诱导的有序化和变形诱导的无序化。在表观弹性体系（小应变）中，老化占主导地位，而变形引起的无序则可以忽略不计。在这种情况下，我们还对广泛使用的拉伸指数函数进行了修改，将变形过程中的原位老化纳入其中。这一修改成功地描述了小变形条件下的应力松弛行为，并为这一过程中的参数演变提供了深入的见解。在大变形条件下，必须同时考虑老化和变形对结构状态的再生效应。通过分析这一过程中缺陷浓度的演变，我们在自由体积理论的框架内描述了相关的实验结果，有效地分离了变形过程中老化和再生对结构状态的贡献。Thin-Walled StructuresTopology Optimization Design of Recoverable Bistable Structures for Energy Absorption with Embedded Shape Memory AlloysKuan Liang, Shaojie Zhou, Yangjun Luo, Xiaopeng Zhang, Zhan Kangdoi:10.1016/j.tws.2024.111757 利用嵌入式形状记忆合金拓扑优化设计用于能量吸收的可恢复双稳态结构In this work, multistable mechanical metamaterials with recoverable capabilities are designed for high energy absorption and resistance to repetitive impacts. Based on the known curved beam with energy dissipation characteristics, the shape memory alloys (SMAs) curved beam is added and optimized to achieve recoverability of the bi-layer beam structure. To simultaneously achieve bistable characteristics and recoverability in the designed metamaterial, the optimization model is formulated to maximize the energy absorption capacity of the structure while constraining the peak and valley forces. To solve this complex and highly nonlinear topological optimization problem with stringent constraints, the topological design of the SMAs layer is represented using a limited number of design variables along with the material-field series expansion strategy, and the optimization problem is subsequently solved using a non-gradient-based optimization algorithm. Finite element simulation results demonstrated that the optimized design possesses a substantial capacity for energy absorption. Additionally, the design structure can recover to its initial state from buckling induced by the initial load by regulating the external temperature. Different multistable metamaterials, including those designed to prevent repetitive impacts, have been further developed based on the designed recoverable high-energy-absorbing bistable unit cells, utilizing combinations of varying energy absorption capacities.在这项工作中，设计了具有可恢复能力的多稳态机械超材料，用于吸收高能量和抵抗重复冲击。在已知具有能量耗散特性的弧形梁的基础上，增加并优化了形状记忆合金（SMAs）弧形梁，以实现双层梁结构的可恢复性。为了在设计的超材料中同时实现双稳态特性和可恢复性，制定了优化模型，以最大限度地提高结构的能量吸收能力，同时限制峰值和谷值力。为了解决这个具有严格约束条件的复杂且高度非线性的拓扑优化问题，SMA 层的拓扑设计采用了有限数量的设计变量和材料-场序列扩展策略，随后使用基于非梯度的优化算法解决了优化问题。有限元模拟结果表明，优化设计具有很强的能量吸收能力。此外，通过调节外部温度，设计结构还能从初始载荷引起的屈曲中恢复到初始状态。在所设计的可恢复高能量吸收双稳态单元单元的基础上，利用不同能量吸收能力的组合，进一步开发了不同的多稳态超材料，包括用于防止重复撞击的超材料。来源：复合材料力学仿真Composites FEM
