Micromechanical investigation of the role of percolation on ductility enhancement in metallic glass composites
Micromechanical investigation of the role of percolation on ductility enhancement in metallic glass composites
复制标题
渗流对金属玻璃复合材料延展性增强作用的微观力学研究
DOI：
10.1016/j.msea.2019.138531
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发表时间：
2020-01
期刊：
影响因子：
6.4
通讯作者：
Gao Yanfei
中科院分区：
文献类型：
--
作者：
Wang Xue;Zhang Wei;Zhao Yanchun;Bei Hongbin;Gao Yanfei
与单块体金属玻璃（BMG）中剪切带无约束传播引起的灾难性失效相反，在BMG复合材料（BMG Cs）中引入第二相提供了一种外在的方式来降低应变局部化的幅度，从而可以显著提高塑性。为了使该机制有效，大量实验已经发现，体积分数应当达到约30- 40%的相当高的阈值，对应于具有取决于第二相形态的变化的逾渗极限。然而，我们在这里证明，增强的延展性可以实现在BMGC由结晶镍泡沫（完全膨胀，甚至与约11%的体积分数），这表明在第二阶段的阻力冲击剪切力偶极子从相邻的剪切带是这样的延展性改善的主导因素。渗流方法的缺点，以及协同效应的微观结构和机械性能的失配，在这里研究的热-机械有限元法的基础上的自由体积模型和塑性诱导加热。延性改善的有效性将通过计算剪切带有效应变的概率分布来证明。
In contrast to the catastrophic failure arising from the unconstrained shear band propagation in monolithic bulk metallic glasses (BMGs), the introduction of second phases in BMG composites (BMGCs) provides an extrinsic way of reducing the magnitude of strain localization, and thus may significantly improve the ductility. For this mechanism to be effective, a multitude of experiments have found that the volume fraction should reach a rather high threshold of about 30–40%, corresponding to the percolation limit with variations depending on the second phase morphology. However, we demonstrate here that an enhanced ductility can be realized in a BMGC made from crystalline Ni foam (completely percolated even with a volume fraction of about 11%), suggesting the resistance in the second phase to the impinging shear-force dipole from neighboring shear bands be the dominant factor for such a ductility improvement. The shortcomings of percolation approach, as well as the synergistic effects of microstructure and mismatches in mechanical properties, are investigated here in a thermo-mechanical finite element method based on the free volume model and plasticity-induced heating. The effectiveness of ductility improvement will be demonstrated by calculating the probability distributions of the shear-band effective strain.
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DOI：
--
发表时间：
2004-09
期刊：
--
影响因子：
--
作者：
M. Sadd
通讯作者：
M. Sadd
CuZr 基大块金属玻璃复合材料的微观结构调整和机械性能的改进
影响因子：
9.4
作者：
Liu, Zengqian;Li, Ran;Zhang, Tao
通讯作者：
Zhang, Tao
影响因子：
9.8
作者：
Haofei Zhou;S. Qu;Wei Yang
通讯作者：
Haofei Zhou;S. Qu;Wei Yang
大块金属玻璃复合材料单轴拉伸和压缩变形行为的数值模拟
影响因子：
6.3
作者：
Wei Rao;Juan Zhang;Guozheng Kang;Peter K. Liaw
通讯作者：
Peter K. Liaw
DOI：
10.1073/pnas.0809000106
发表时间：
2008-12-23
影响因子：
11.1
作者：
Hofmann, Douglas C.;Suh, Jin-Yoo;Johnson, William L.
通讯作者：
Johnson, William L.