摘要
When a crack is subjected to shear force, crack branching usually occurs. Theoretical study shows that the crack branching under shear loading is caused by tensile stress, but not caused by shear fracture. The co plane shear fracture could be obtained if compressive stress with given direction is applied to the specimen, subsequently, calculated shear fracture toughness, K ⅡC , is larger than K ⅠC . A prerequisite of possible occurrence of mode Ⅱ fracture was proposed. The study of shear fracture shows that the maximum circumferential stress theory considered its criterion as a parametric equation of a curve in K Ⅰ, K Ⅱ plane is incorrect; the predicted ratio K ⅡC / K ⅠC =0.866 is incorrect too. [
When a crack is subjected to shear force, crack branching usually occurs. Theoretical study shows that the crack branching under shear loading is caused by tensile stress, but not caused by shear fracture. The co-plane shear fracture could be obtained if compressive stress with given direction is applied to the specimen, subsequently, calculated shear fracture toughness, K (IIC), is larger than K (Ic). A prerequisite of possible occurrence of mode II fracture was proposed. The study of shear fracture shows that the maximum circumferential stress theory considered its criterion as a parametric equation of a curve in K (I) , K (II) plane is incorrect; the predicted ratio K (IIC)/K (IC) = 0.866 is incorrect too.
出处
《中国有色金属学会会刊：英文版》
CSCD
2001年第2期287-292,共6页
Transactions of Nonferrous Metals Society of China
基金
Project ( 4 9672 164 )supportedbytheNationalNaturalScienceFoundationofChina
