论文标题
拉伸变形期间的应变定位和无序颗粒筏具有可调延展性的失败
Strain localization and failure of disordered particle rafts with tunable ductility during tensile deformation
论文作者
论文摘要
对模型无序的固体进行了准静态拉伸实验，该固体由二维筏和带有毛细管吸引力的二维式浮动颗粒颗粒。通过控制毛细管相互作用范围来调节延展性，该毛细管相互作用范围随粒径而变化。在拉伸测试期间，在弹性变形的最初时期后，发生应变定位，并导致形成剪切带，该剪切带后来失败。在此过程中，具有远程相互作用的小颗粒可以忍受大型塑性变形而不会形成明显的空隙，而具有短距离相互作用的大颗粒会因小变形时的分裂而极大地失败。测量了粒子水平的结构，发现应变定位区域的结构各向异性高于整体。各向异性位点和粒子重排之间的局部相互作用是驱动应变定位和随后失败的主要机制，并且这种相互作用存在延展性和脆性行为之间的显着差异。
Quasi-static tensile experiments were performed for a model disordered solid consisting of a two-dimensional raft of polydisperse floating granular particles with capillary attractions. The ductility is tuned by controlling the capillary interaction range, which varies with the particle size. During the tensile tests, after an initial period of elastic deformation, strain localization occurs and leads to the formation of a shear band at which the pillar later fails. In this process, small particles with long-ranged interactions can endure large plastic deformations without forming significant voids, while large particles with short-range interactions fail dramatically by fracturing at small deformation. Particle-level structure was measured, and the strain-localized region was found to have higher structural anisotropy than the bulk. Local interactions between anisotropic sites and particle rearrangements were the main mechanisms driving strain localization and the subsequent failure, and significant differences of such interactions exist between ductile and brittle behaviors.
