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由液体金属脆断的断裂韧性K_(IC)(L)可算出裂纹扩展的阻力R=(1-v~2)K_(IC)~2(L)/E,它比材料的表面能γ大1～3个数量级.因而不能用Griffith脆性断裂理论R=2γ来描述,只能用Orowan理论,即R=2γ_(eff)=2γ+γ_p,其中γ_p 为局部塑性变形功. 对于液体金属脆,实验测出塑性变形功γ_p=(10～1000)γ.这表明,液体金属吸附而导致脆断的过程伴随大量的局部塑性变形,而且断裂能主要消耗在局部塑性变形上.
The fracture resistance R (1-v ~ 2) K IC (IC) ~ 2 (L) / E of the crack propagation can be calculated from the fracture toughness K IC (L) brittle fracture of the liquid metal, which is larger than the surface energy γ of the material 1 ~ 3 orders of magnitude, and therefore can not be described by Griffith’s brittle fracture theory R = 2γ, but only Orowan’s theory, ie R = 2γ_eff = 2γ + γ_p, where γ_p is the local plastic deformation work.For liquid metal brittleness, The experimentally determined plastic deformation work γ_p = (10 ~ 1000) γ shows that the process of liquid metal adsorption caused brittle fracture with a large number of local plastic deformation, and the fracture energy can be mainly consumed in the local plastic deformation.