裂尖张开位移与伸张区宽度的关系

The Relationship between Crack Tip Opening Displacement and Stretch Zone Width

采用屈服强度在138-878 MPa之间的几种材料的试验数据,考查了前人提出的材料性能对伸张区宽度与裂尖张开位移比值(WSZ／δ)的影响规律。结果表明:Prantl提出WSZ／δ的值与材料的应变硬化指数和屈服强度之间的关系与试验结果吻合较差,根本原因在于其推导过程中采用的假设前后矛盾。WSZ／δ值与流变应力呈近似线性关系,而不是呈正比关系。

The relationships between Wsz/δ value and properties of materials proposed by some investigations are discussed by using experimental data of several materials whose yield strength is in a range of 138-878 MPa. The influences of strain-hardening exponent and yield strength on Wsz/δ value suggested by Prantl do not have a good agreement with experimental data. The major reason should be that some assumptions used in the deduction process are contradictory. The Wsz/δ value seems to be linear instead of proportional to flow stress.