【新文速递】2024年8月1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，International Journal of Plasticity 1 篇，Thin-Walled Structures 3 篇

Journal of the Mechanics and Physics of Solids

Mechanochemical patterning and wave propagation in multicellular tubes

Pengyu Yu, Bo Li

doi:10.1016/j.jmps.2024.105801

多细胞管中的机械化学模式和波传播

Multicellular tubes are fundamental tissues for transporting and distributing liquids and gases in living organisms. Although the molecular, cellular and mechanical aspects in tube formation have been addressed experimentally, how these factors are coupled to control tube patterning and dynamics at the tissue level remains incompletely understood. Here, we propose a three-dimensional (3D) vertex model that incorporates a mechanochemical feedback loop correlating cell deformation and actomyosin signaling pathway to probe the morphodynamics of multicellular tubes. We show that diverse patterns, including ring, helix, double helix, and labyrinth, are generated in tubes through pitchfork bifurcation, where spatial fluctuations of both biochemical signaling and 3D cell deformation are remarkably involved. The mechanochemical feedback loop enables cell oscillations via Hopf bifurcation, which induces the mechanical and chemical patterns to propagate successively as either travelling or pulse waves while their spatial configurations are maintained, strikingly distinct from the classical Turing instability. Our simulations, together with stability analysis of a minimal model, uncover the essential role of mechanochemical principles in sculpting biological tubes.

多细胞管是生物体内运输和分配液体和气体的基本组织。虽然试管形成的分子、细胞和力学方面已经在实验中得到了解决，但这些因素如何耦合到组织水平上控制试管的模式和动力学仍然不完全清楚。在这里，我们提出了一个三维(3D)顶点模型，该模型结合了与细胞变形和肌动球蛋白信号通路相关的机械化学反馈回路，以探测多细胞管的形态动力学。我们发现不同的模式，包括环，螺旋，双螺旋和迷宫，通过干草叉分叉在管中产生，其中生化信号和三维细胞变形的空间波动显著参与。机械化学反馈回路通过Hopf分岔使细胞振荡，这诱导机械和化学模式作为行波或脉冲波连续传播，同时保持它们的空间构型，与经典的图灵不稳定性明显不同。我们的模拟，连同最小模型的稳定性分析，揭示了机械化学原理在雕刻生物管中的重要作用。

Mechanics of Materials

Medium entropy alloy-induced strong size dependence in the strengthening and shear instability of nanolayered metallic composites

Feng Qin, Kaiqing Dai, Junhua Hou, Wenjun Lu, Shaohua Chen, Jianjun Li

doi:10.1016/j.mechmat.2024.105107

中熵合金对纳米层金属复合材料的增强和剪切失稳具有很强的尺寸依赖性

Medium/high entropy alloys (M/HEAs)-based nanolayered metallic composites have attracted intensive scientific interests due to their superior mechanical properties. However, the shear instability of the M/HEAs-based composites is rarely studied and the underlying mechanism remains uncovered. A combination of theoretical analysis and nano/microindentation tests was conducted to investigate the size-dependent strengthening and shear instability of Cu/CrCoNi composites. The results show that the shear banding-induced instability of the composites exhibit a clear transition from layer interfaces-mediated kinking to grain boundaries-accommodated one at a critical layer thickness of 25 nm, which apparently differs from those in traditional M/HEAs-free composites. The sudden change in the deformation mode originates from the MEA-induced size-dependent microstructure transformation, i.e., from horizontally aligned layer interfaces at large layer thicknesses to vertically aligned grain boundaries at small ones. The size-dependent strengthening and plasticity can be respectively captured by the confined layer slip model and the proposed theoretical model.

中高熵合金(M/HEAs)基纳米层金属复合材料以其优异的力学性能引起了科学界的广泛关注。然而，对M/ heas基复合材料剪切失稳的研究很少，其潜在机制也尚未揭示。采用理论分析和纳米/微压痕试验相结合的方法研究了Cu/CrCoNi复合材料的尺寸依赖性强化和剪切不稳定性。结果表明，在25 nm的临界层厚处，剪切带诱导的复合材料的失稳表现出从层界面介导的扭结到晶界调节的扭结的明显转变，这与传统的无M/ heas复合材料明显不同。变形模式的突变源于mea诱导的尺寸相关的微观结构转变，即从大层厚处水平排列的层界面到小层厚处垂直排列的晶界。约束层滑移模型和本文提出的理论模型可以分别捕获与尺寸相关的强化和塑性。

International Journal of Plasticity

Chromium Gradient Stainless Steels with Simultaneous High Strength, Ductility, and Corrosion-resistant: In-depth Study of Continuous Hardening Mechanisms

Haodi Yang, Zhutian Xu, Linfa Peng, Xinmin Lai, Mingwang Fu

doi:10.1016/j.ijplas.2024.104082

同时具有高强度、延展性和耐腐蚀性的铬梯度不锈钢:连续硬化机制的深入研究

Cr-rich stainless steel sheets exhibit superior corrosion resistance but low ductility, which presents a trade-off between fabrication complexity and performance of the materials in multiple industrial applications, such as marine equipment and microreactors. By transitioning the Cr-rich (30 wt.% Cr) stainless steel component to SS 316L with a smooth composition gradient in the thickness direction, the intrinsic homogeneous elongation of the Cr-rich layer was increased by 260 % while maintaining the naturally high corrosion resistance (100 %) and retaining most of the strength (more than 80 %). By employing in-situ tensile testing and electron backscatter diffraction analysis, it was revealed that the Cr-rich layer in the gradient structure underwent a profound deformation mechanism, including significant heterogeneous deformation-induced hardening and grain reorientation induced by multiplication and accumulation of geometrically necessary dislocations, in such a way to enable a substantial plastic strain and thereby retarding the occurrence of fracture. The proportion of the Cr-rich layer makes a significant impact on the magnitude of the strain gradient in the gradient specimens, therefore affecting the increment of density of geometrically necessary dislocations. The critical proportion value of the Cr-rich layer is found to be around 22 %. Before and after the critical value the gradient specimens showed different sensitivities to the proportion. This discovery underlines the significance of intrinsic plasticity in low-ductility metals and the role of compositional gradient materials in enhancing strength and ductility.

富铬不锈钢板具有优异的耐腐蚀性，但延展性低，这在多种工业应用(如船舶设备和微反应器)中提出了制造复杂性和材料性能之间的权衡。通过将富Cr (30wt .% Cr)不锈钢组分转变为具有光滑厚度梯度的SS 316L，富Cr层的本构均匀伸长率提高了260%，同时保持了天然的高耐腐蚀性(100%)和大部分强度(80%以上)。通过原位拉伸测试和电子背散射衍射分析，发现梯度结构中的富cr层发生了深刻的变形机制，包括显著的非均质变形诱导的硬化和几何必要位错的增殖和积累引起的晶粒重定向，从而产生了大量的塑性应变，从而延缓了断裂的发生。富cr层的比例对梯度试样中应变梯度的大小有显著影响，从而影响几何必要位错密度的增量。富cr层的临界比例值在22%左右。在临界值前后，梯度试样对比例的敏感性不同。这一发现强调了低延性金属的内在塑性的重要性，以及成分梯度材料在提高强度和延性方面的作用。

Thin-Walled Structures

Experimental, numerical, and analytical studies of asymmetric bolted square hollow section splices in bending

Rui Yan, Milan Veljkovic, Luís Simões Da Silva

doi:10.1016/j.tws.2024.112282

非对称螺栓方空心截面接头弯曲的实验、数值和分析研究

The flexural behaviour of two types of asymmetric bolted square hollow section (SHS) splices is investigated in this paper. The asymmetric bolted SHS splices are derived from the traditional bolted end plate SHS joints but with the end plate flushed to the SHS surface on one side or two adjacent sides, where a cover plate connects two SHSs. Firstly, four-point bending tests are conducted for two configurations under different loading conditions. Next, finite element (FE) analysis is carried out to simulate the experiments. To reduce the computational time, a simplified FE model is developed, which is further employed for a parametric study. Finally, the component method, which was extended for the asymmetric bolted SHS splices under tensile load, is verified against the FE models in the parametric study. The results show that the extended component method could effectively predict the stiffness and the resistance of bolted asymmetric SHS splices under different bending loads.

本文研究了两种非对称螺栓方空心截面(SHS)接头的抗弯性能。非对称螺栓连接SHS是在传统螺栓端板SHS连接的基础上发展而来的，但其端板在一侧或相邻的两侧冲到SHS表面，其中盖板连接两个SHS。首先，对两种结构进行了不同加载条件下的四点弯曲试验。其次，对实验进行了有限元模拟分析。为了减少计算时间，建立了一个简化的有限元模型，并将其进一步用于参数化研究。最后，通过参数化研究中的有限元模型验证了对拉伸载荷作用下非对称螺栓SHS接头的构件分析方法。结果表明，扩展分量法可以有效地预测不同弯曲载荷下螺栓非对称SHS接头的刚度和阻力。

Nonlinear vibrations of variable speed rotating graphene platelets reinforced blades subjected to combined parametric and forced excitation

Jin-Peng Song, Gui-Lin She, M.A. Eltaher

doi:10.1016/j.tws.2024.112283

参数激励与强制激励联合作用下石墨烯片增强叶片的非线性振动

It is generally acknowledged that the disturbance of rotating speed will cause parametric resonance for blades, and the presence of rotor displacement also can make the blade vibrate transversely. However, the coupled resonance mechanism of blades under the combined action of rotating speed disturbance and rotor displacement is not yet clear. To answer this question, this article investigates the nonlinear coupled resonance behavior of rotating blades in two cases: typical tuned (the frequency ratio of parametric and forced excitations equals 2:1) and frequency ratio detuned. A nonlinear vibration equation for rotating blades is established based on Euler beam theory in conjunction with geometric nonlinearity. The mixing rule and modified Halpin-Tsai model are used to calculate the effective properties of GPLRMF materials. Subsequently, using the method of varying amplitudes (MVA), an approximate analytical solution of the coupled resonance response is derived, the Jacobian matrix is used to determine the stability of non-trivial solutions, and the accuracy of the analytical results is verified with the aid of numerical solutions. Finally, the steady-state response of typical tuned and detuned coupled resonance is analyzed, and the influence mechanism of factors such as excitation amplitude, excitation phase angle and other parameters on coupled resonance is studied in detail. The results indicate that the supercritical coupled resonance curve exhibits double resonance peaks and jumps. Meanwhile, the steady-state response of coupled resonance highly depends on the excitation phase angle.

一般认为转速的扰动会引起叶片的参数共振，转子位移的存在也会使叶片产生横向振动。然而，叶片在转速扰动和转子位移共同作用下的耦合共振机理尚不清楚。为了回答这个问题，本文研究了两种情况下旋转叶片的非线性耦合共振行为:典型调谐(参数激励与强迫激励的频率比等于2:1)和频率比调谐。基于欧拉梁理论，结合几何非线性，建立了旋转叶片的非线性振动方程。采用混合规则和修正的Halpin-Tsai模型计算了GPLRMF材料的有效性能。随后，采用变幅法推导了耦合共振响应的近似解析解，利用雅可比矩阵确定了非平凡解的稳定性，并借助数值解验证了解析结果的准确性。最后，分析了典型调谐和失调谐耦合谐振的稳态响应，详细研究了激励幅值、激励相位角等参数对耦合谐振的影响机理。结果表明，超临界耦合共振曲线呈现双共振峰和双共振跳变。同时，耦合谐振的稳态响应高度依赖于激励相位角。

Cushioning Performance of Origami Negative Poisson's ratio Honeycomb Steel Structure

Yiyi Zhou, Dan Jiang, Lu Wang, Ping Xiang, Liang-Jiu Jia

doi:10.1016/j.tws.2024.112284

折纸负泊松比蜂窝钢结构的减震性能

The honeycomb structure with a negative Poisson's ratio, inspired by the Miura origami unit, exhibits three-dimensional negative Poisson's ratio characteristics and effective energy dissipation performance. This unique property provides significant potential in the field of protection applications. This study aims to comprehensively understand the impact of auxetic and origami structures on the cushioning performance of honeycomb structures. For this purpose, 316L stainless steel specimens were fabricated using 3D printing technology and subjected to drop hammer impact tests, and the results were verified by finite element simulation. This paper focuses on assessing the deformation mode and energy dissipation performance of origami auxetic honeycomb structures with varying width-to-thickness ratios and folding angles under different impact energy levels. The results indicate that the negative Poisson's ratio origami specimens exhibit higher plateau stress and specific energy absorption compared to their positive and zero Poisson's ratio origami counterparts with the same geometry. In addition, a smaller width-to-thickness ratio and higher input impact energy enhance the cushioning performance of honeycomb structures.

负泊松比的蜂窝结构，受折纸单元的启发，具有三维负泊松比特性和有效的能量耗散性能。这种独特的特性在保护应用领域提供了巨大的潜力。本研究旨在全面了解辅助结构和折纸结构对蜂窝结构缓冲性能的影响。为此，采用3D打印技术制作316L不锈钢试件，进行落锤冲击试验，并通过有限元模拟对结果进行验证。研究了在不同冲击能级下，不同宽厚比和折叠角度的折纸减振蜂窝结构的变形模式和耗能性能。结果表明，与相同几何形状的正泊松比和零泊松比折纸相比，负泊松比折纸具有更高的平台应力和比能吸收。此外，较小的宽厚比和较高的输入冲击能增强了蜂窝结构的缓冲性能。