裂尖大变形条件下的约束研究  

The Study of the Constraint Effect under Large Scale Yield at Crack Tip

作　　者：徐绯[1] 郭万林[2] 李强 

机构地区：[1]西北工业大学,西安710072 [2]南京航空航天大学 [3]西安航空发动机集团公司

出　　处：《力学季刊》2002年第1期99-104,共6页Chinese Quarterly of Mechanics

摘　　要：通过对面内应力比T_x和离面约束T_x在塑性区分布规律的深入分析,发现约束在塑性区不同区域的影响是不同的,在裂尖的钝化区,面内应力比T_x起重要作用,而在钝化区外的塑性区内,离面约束T_x起主要作用;在J-Q理论的基础上引入离面约束T_z可以很好地描述钝化区以外的应力应变分布,在钝化区内引入面内应力比T_x可以对裂尖前方的应力应变进行大变形分析和描述。研究表明综合两个约束的共同作用,可以很好地描述大变形条件下裂尖前方的应力分布。The effects of two parameters, the in-plane stress ratio Tx and the out-of-plane constraint T, were carefully studied by means of the finite element method. In the blunt zone, the influence of in-plane stress ratio is stronger than that of the out-of-plane constraint; while out of the blunt zone, the out-of-plane constraint is more important. Based on the J-Q theory and the influence of out-of-plane constraint, the stress and strain fields in the out of blunt zone can be predicted very well. However the blunt effect must be prescribed using the in-plane stress ratio. In a word, the stress and strain distributions at whole plastic zone are strongly affected by these two parameters under large scale yield condition.

关 键 词：裂尖场 钝化区 约束 离面约束 

分 类 号：O347.3[理学—固体力学] O346.12[理学—力学]