【新文速递】2024年8月1日复合材料SCI期刊最新文章_ACT_Mechanical_Additive_System_MAGNET_断裂_复合材料_非线性_化学_电路_通用_航空_电子_增材_裂纹_理论_材料_数字孪生

【新文速递】2024年7月5日固体力学SCI期刊最新文章

今日更新：Journal of the Mechanics and Physics of Solids 1 篇，Mechanics of Materials 1 篇，Thin-Walled Structures 1 篇Journal of the Mechanics and Physics of SolidsStretch-independent magnetization in incompressible isotropic hard magnetorheological elastomersKostas Danas, Pedro M. Reisdoi:10.1016/j.jmps.2024.105764不可压缩的各向同性硬磁流变弹性体中与拉伸无关的磁化Recent studies on magnetically hard, particle-filled magnetorheological elastomers ( h -MREs) have revealed their stretch-independent magnetization response after full pre-magnetization. We discuss this phenomenon, focusing on incompressible, isotropic, particle-filled h -MREs. We demonstrate that the fully dissipative model of Mukherjee et al. (2021) for arbitrary loads can be reduced, under physically consistent assumptions, to the energetic model of Yan et al. (2023), but not that of Zhao et al. (2019). The latter two are valid for small magnetic fields around an already known pre-magnetized state. When the pre-magnetized h − MRE undergoes non-negligible stretching, the Zhao et al. (2019) model yields predictions that disagree with experiments due to its inherent stretch-dependent magnetization response. In contrast, the Mukherjee et al. (2021) and Yan et al. (2023) models are able to accurately capture this important feature present in pre-stretched h -MREs. However, for inextensible slender structures under bending deformation, where stretching is negligible, the Zhao et al. (2019) model provides satisfactory predictions despite its underlying assumptions. Our analysis reveals that, in the fully dissipative model, magnetization can be related to an internal variable but cannot be formally used as one, except for ideal magnets, and is subject to constitutive assumptions. Furthermore, the magnetization vector alone is insufficient to describe the magnetic response of an MRE solid; the introduction of one of the original Maxwell fields is necessary for a complete representation.最近对磁性硬质颗粒填充磁流变弹性体（h -MREs）的研究表明，在完全预磁化后，它们的磁化响应与拉伸无关。我们讨论了这一现象，重点是不可压缩、各向同性、颗粒填充的 h -MRE。我们证明，在物理条件一致的假设下，Mukherjee 等人（2021 年）针对任意载荷的全耗散模型可以简化为 Yan 等人（2023 年）的能量模型，但赵等人（2019 年）的模型则不行。后两者适用于已知预磁化状态周围的小磁场。当预磁化的 h - MRE 经历不可忽略的拉伸时，赵等人（2019）的模型由于其固有的拉伸依赖性磁化响应，得出的预测结果与实验结果不一致。相比之下，Mukherjee 等人（2021 年）和 Yan 等人（2023 年）的模型能够准确捕捉到预拉伸 h -MRE 的这一重要特征。然而，对于弯曲变形下的不可拉伸细长结构，拉伸可以忽略不计，赵等人（2019）的模型尽管有其基本假设，但还是提供了令人满意的预测。我们的分析表明，在完全耗散模型中，磁化可以与内部变量相关，但除了理想磁体外，不能正式作为内部变量使用，并且受制于构成假设。此外，仅凭磁化矢量不足以描述 MRE 固体的磁响应；要获得完整的表示，必须引入一个原始麦克斯韦场。Mechanics of MaterialsModelling of Mode I crack-tip dislocation nucleation in three FCC materials: Ni, Cu and AlXiaodong He, Weigang Zhang, Xiaochen Lidoi:10.1016/j.mechmat.2024.105068三种催化裂化材料中的模式 I 裂纹尖端位错成核建模：镍、铜和铝An accurate estimation of the critical stress intensity factor for crack tip dislocation nucleation under Mode I loading is of great importance to determine whether a material is intrinsically ductile or not. Here, shear displacements and energy change at crack tip in FCC nickel, copper and aluminum are investigated during Mode I fracture process using atomistic simulations. In light of our simulation results, a new shear resistance model is formulated by a general Fourier expansion with coefficients identified by the computed energy curve. The new model involving the step formation energy which can be regarded as a new parameter and unstable stable stacking fault energy, reduces to Rice theory if no step exists. The criterion for nucleation is developed based on the idea that crack tip behaviors are controlled by the shear resistance and the maximum point serves as an obstacle to conquer. The predictions of the critical shear displacement corresponding to maximum shear resistance position and the critical nucleation energy show good agreement with simulation results. In addition, the new model can be further utilized to study the effect of complex stress state on Mode I crack tip dislocation nucleation.准确估算模式 I 加载下裂纹尖端位错成核的临界应力强度因子对于确定材料是否具有内在延展性非常重要。在此，我们利用原子模拟研究了 FCC 镍、铜和铝在模式 I 断裂过程中裂纹尖端的剪切位移和能量变化。根据我们的模拟结果，通过一般傅里叶扩展建立了一个新的剪切阻力模型，其系数由计算出的能量曲线确定。新模型涉及阶梯形成能量（可视为一个新参数）和不稳定的稳定堆积断层能量，如果不存在阶梯，则还原为赖斯理论。根据裂纹尖端行为受剪切阻力控制，而最大点是征服裂纹的障碍这一观点，提出了成核标准。与最大剪切阻力位置相对应的临界剪切位移和临界成核能量的预测结果与模拟结果显示出良好的一致性。此外，新模型还可进一步用于研究复杂应力状态对模式 I 裂纹尖端位错成核的影响。Thin-Walled StructuresDevelopment and application of out-of-plane deformable X-shaped brace for energy dissipation and thermal stress mitigation: An experimental and numerical studyJing-Cong Lin, Xiao-Lei Han, Zi-Nan Wu, You Dong, Jing Ji, Juncai Liudoi:10.1016/j.tws.2024.112186开发和应用平面外可变形 X 形支架，用于消能和减缓热应力：实验和数值研究Exoskeleton systems are increasingly employed in both new and existing buildings to enhance seismic performance. Addressing the critical challenges of energy dissipation and thermal stress mitigation in these systems, an out-of-plane deformable X-shaped energy dissipation brace (OPD-XEDB), integrating an out-of-plane X-shaped brace with a shear-type metallic damper, was proposed in this study. A seismic design methodology for OPD-XEDB was firstly developed, ensuring effective energy dissipation of the damper before any potential brace buckling. Following this methodology, two specimens, exhibiting distinct failure modes of damper shear fracture and brace buckling, were designed and subjected to quasi-static loadings to explore their energy dissipation mechanisms. Upon these experimental results, a numerical model incorporating buckling and pinching behaviors was proposed and calibrated, effectively capturing the hysteretic responses of the specimens. This model was then employed in a comprehensive numerical analysis, validating the effectiveness of design methodology and determining the optimal specifications for the OPD-XEDB in a prototype building. Ultimately, thermal analysis and nonlinear time history analysis were conducted on the prototype building. The thermal analysis proved the effectiveness of the OPD-XEDB's out-of-plane configuration in mitigating thermal stress by out-of-plane deformation, significantly mitigating thermal stress in braces and interconnected moment frames by 96.59-96.66%. The time history analysis revealed that the dampers in OPD-XEDBs dissipated 11.6-23.2% of total seismic energy, effectively preventing substantial buckling in the X-shaped braces. This energy dissipation mechanism led to a remarkable 79.7% reduction in steel consumption for post-earthquake retrofitting, thereby significantly enhancing the seismic resilience of the primary structure.为提高抗震性能，新建建筑和现有建筑越来越多地采用外骨骼系统。为了解决这些系统中能量耗散和热应力减缓的关键难题，本研究提出了一种平面外可变形 X 形能量耗散支撑（OPD-XEDB），它将平面外 X 形支撑与剪切型金属阻尼器集成在一起。首先开发了 OPD-XEDB 的抗震设计方法，确保阻尼器在可能发生支撑屈曲之前有效消能。根据该方法，设计了两个表现出阻尼器剪切断裂和支撑屈曲两种不同失效模式的试样，并对其进行了准静态加载，以探索其能量耗散机制。根据这些实验结果，提出并校准了一个包含屈曲和挤压行为的数值模型，有效地捕捉到了试样的滞后响应。该模型随后被用于综合数值分析，验证了设计方法的有效性，并确定了 OPD-XEDB 在原型建筑中的最佳规格。最后，对原型建筑进行了热分析和非线性时间历程分析。热分析表明，OPD-XEDB 的平面外配置能有效地通过平面外变形减轻热应力，在支撑和相互连接的力矩框架中显著减轻了 96.59-96.66% 的热应力。时间历程分析表明，OPD-XEDB 中的阻尼器耗散了总地震能量的 11.6-23.2%，有效防止了 X 型支撑的大幅屈曲。这种消能机制显著减少了 79.7% 的震后改造钢材消耗，从而大大提高了主结构的抗震能力。来源：复合材料力学仿真Composites FEM

【新文速递】2024年8月1日复合材料SCI期刊最新文章

Composite Structures

Composites Part A: Applied Science and Manufacturing

Composites Science and Technology

【新文速递】2024年7月5日固体力学SCI期刊最新文章