【新文速递】2024年2月6日固体力学SCI期刊最新文章
今日更新：International Journal of Plasticity 1 篇，Thin-Walled Structures 1 篇
International Journal of Plasticity
Tailoring the adiabatic shear susceptibility of pure tungsten via texture evolution
Xiukai Kan, Jianguo Li, Jingui Zhong, Tao Suo
doi:10.1016/j.ijplas.2024.103909
通过纹理演变调整纯钨的绝热剪切感应性
Pure tungsten (W) is generally believed to be a preferred alternative material for kinetic penetrators once a “self-sharpening” effect can be realized by inducing adiabatic shear failure during high-speed impact. However, it is still a major challenge to trigger adiabatic shear bands (ASBs) in pure W with low ductility. In this work, we reported an improved adiabatic shear susceptibility of pure W by controlling the texture evolution during the pre-rolling process. As the rolling strain increased, the texture components and intensity underwent crucial variations to facilitate the appearance of ASBs. For comparative studies, we investigated the dynamic behavior of three kinds of W samples with different microstructural features at a wide range of temperatures (298K∼1473K) via SHPB system, including coarse-grained W (CGW), as-rolled W samples to the thickness reductions of 75% (75W) and 80% (80W). The experimental results revealed a transition of failure behavior from typical brittle fracture to adiabatic shear instability under uniaxial dynamic compression. Of particular interest was that although 75W and 80W exhibited almost the same mechanical properties after the similar rolling reductions, their dynamic instability behaviors differed remarkably with different spatial distributions of texture components. In the as-rolled 75W, two dominant texture components of {001}<110> and {111}<110> were alternate to form fully spaced layers. Under uniaxial compression, the {111}<110> “hard orientation layers” became the obstacles to the propagation of ASBs. Fortunately, in 80W specimens the different {001}<110> “soft orientation layers” were interconnected by the “soft bricks” of the same orientation, which provided pathways for the expansion of shear localization and ultimately the triggering of ASBs. Through subsequent crystal plasticity finite element (CPFEM) simulations, we further verified the effect of orientation distributions on the shear localization and thoroughly explained the formation mechanism of ASBs in the highly textured refractory metal. This may provide guidance for producing advanced materials for certain practical applications.
一般认为，一旦在高速撞击过程中诱发绝热剪切破坏，从而实现 "自锐化 "效果，纯钨（W）就会成为动能穿甲弹的首选替代材料。然而，在延展性较低的纯 W 中引发绝热剪切带（ASB）仍然是一个重大挑战。在这项工作中，我们报告了通过控制预轧过程中的纹理演变来改善纯 W 的绝热剪切敏感性。随着轧制应变的增加，纹理成分和强度发生了重要变化，从而促进了 ASB 的出现。为了进行比较研究，我们通过 SHPB 系统研究了三种具有不同微观结构特征的 W 样品在宽温度范围（298K∼1473K）下的动态行为，包括粗晶粒 W（CGW）、厚度减少 75% （75W）和 80% （80W）的轧制 W 样品。实验结果表明，在单轴动态压缩下，破坏行为从典型的脆性断裂过渡到绝热剪切不稳定性。特别值得注意的是，虽然 75W 和 80W 在经过类似的轧制减薄后表现出几乎相同的机械性能，但它们的动态失稳行为却因纹理成分的空间分布不同而存在显著差异。在轧制后的 75W 中，{001}<110> 和 {111}<110> 两种主要纹理成分交替形成完全间隔的层。在单轴压缩下，{111}<110>"硬取向层 "成为 ASB 传播的障碍。幸运的是，在 80W 试样中，不同的{001}<110>"软取向层 "由相同取向的 "软砖 "相互连接，这为剪切定位的扩展提供了途径，并最终引发了 ASB。通过随后的晶体塑性有限元（CPFEM）模拟，我们进一步验证了取向分布对剪切定位的影响，并深入解释了高纹理难熔金属中 ASB 的形成机制。这为生产某些实际应用的先进材料提供了指导。
Thin-Walled Structures
Mechanics of a thin-walled segmented torus snap fit
Xiao-Lin Guo, Bo-Hua Sun
doi:10.1016/j.tws.2024.111676
薄壁分段环形扣合的力学原理
The snap fit is a commonly used jointing/connention mechanism because it is simple and reusable, and its easy installation and difficult removal are the result of the coordinated interaction between friction, geometric shape, and elasticity. This paper presents a detailed study on the assembly/disassembly forces of thin-walled torus snap-fit through finite element simulation, experimental testing, and data fitting of approximate analytical solutions. The research reveals that the non-zero Gaussian curvature of the torus has a significant impact on the mechanical performance of the torus snap fit. The findings in this study are of great significance for future design of high-performance structural connections.
卡合是一种常用的接合/连接机构，因为它简单且可重复使用，其易安装和难拆卸是摩擦力、几何形状和弹性之间协调作用的结果。本文通过有限元仿真、实验测试和近似分析解的数据拟合，对薄壁环形卡接的装配/拆卸力进行了详细研究。研究发现，环的非零高斯曲率对环形卡接件的机械性能有重大影响。本研究的发现对未来高性能结构连接的设计具有重要意义。
