图5. Mohr-Coulomb准则对韧性金属玻璃剪切断裂行为预测的几种情况^[95]

Fig.5. Several cases for predicting the shear fracture behaviors of MG by the Mohr-Coulomb criterion^[95]
(a) conventional case, i.e., coefficient of internal friction μ and critical shear serength τ₀ are constant for all stress state (τ and σ are the shear stress and normal stress acted on shear plane, respectively; σCFand σTFare compressive and tensile fracture strength, respectively)
(b) different μ for tension and compression to achieve the correct predictions of shear fracture angles (θ_C and θ_T)
(c) different μ and τ₀ for tension and compression to achieve the correct predictions of both the shear fracture angles and the fracture strength (τ0T and τ0C are the critical shear stresses that derived from tensile and compressive fracture strength and fracture angles according to the Mohr-Coulomb criterion, respectively)
(d) plot of the Mohr-Coulomb criterion and the Mohr's circle with shear strength of τ₀
(e) modified parameter of critical shear strength τ0M-C in the criterion to achieve the correct predictions of pure shear strength of τ₀