A study of the effect of Poisson's ratio on the stationary mode I crack tip fields in amorphous alloys is conducted. Finite element simulations under plane strain, small scale yielding conditions are performed with a Mohr-Coulomb based constitutive model that accounts for pressure sensitivity of plastic flow as well as the localization of plastic strain into discrete shear bands. Simulations are also performed with von Mises and Drucker-Prager constitutive models. While the Poisson's ratio does not alter the crack tip fields significantly when the material obeys these two models, it has a marked influence in the Mohr-Coulomb case with softening. A higher Poisson's ratio reduces the extent of plastic zone and plastic strain levels in front of the notch tip as well as that within the simulated shear bands around the notch root at a given level of stress intensity factor. The implications of these observations on toughness of metallic glasses are discussed.
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机译：研究了泊松比对非晶合金稳态I型裂纹尖端场的影响。使用基于Mohr-Coulomb的本构模型在平面应变、小尺度屈服条件下进行有限元模拟，该模型考虑了塑性流动的压力敏感性以及塑性应变在离散剪切带中的定位。还使用 von Mises 和 Drucker-Prager 本构模型进行仿真。虽然当材料服从这两个模型时，泊松比不会显着改变裂纹尖端场，但它在 Mohr-Coulomb 软化情况下具有显着影响。在给定的应力强度因子水平下，较高的泊松比可降低缺口尖端前方的塑性区和塑性应变水平，以及缺口根部周围模拟剪切带内的范围。讨论了这些观察结果对金属玻璃韧性的影响。
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