Ⅰ+Ⅱ复合型弹塑性断裂的COD分析  

COD ANALYSIS FOR ELASTIC-PLASTIC FRACTURE UNDER MIXED MODE LOADING

作　　者：沙江波[1] 朱平[2] 邓增杰[2] 周惠久[2] 

机构地区：[1]广东工业大学材料工程系,广州510090 [2]西安交通大学材料科学与工程学院,西安710049

出　　处：《固体力学学报》1997年第3期258-263,共6页Chinese Journal of Solid Mechanics

基　　金：国家教委博士点基金

摘　　要：以Rice的裂纹尖端钝化模型为基础定义了复合载荷下裂纹尖端的位移COD、CTOD和CTSD，CTOD和CTSD是复合型裂尖位移COD的Ⅰ和Ⅱ型分量．对铝合金Ly12复合Ⅰ＋Ⅱ型弹塑性断裂行为进行了COD分析，并对复合载荷下COD与J积分的关系进行了讨论．结果表明：（1）随Ⅱ型分量的增加，Ly12启裂的CODi值增加，纯Ⅱ型的启裂CODi值是纯Ⅰ型的6倍；（2）Ly12复合载荷下的COD与复合J积分值JM满足下列关系：JM=dσ0COD，d为系数，随复合比而变，可由实验和计算确定．Based on the mere blunting model proposed by Rice, the crack tip displacements COD,CTOD and CTSD under mixed Ⅰ+Ⅱ loading were defined, where CTOD and CTSD are the mode Ⅰ and the mode Ⅱ components of COD, respectively. The COD、CTOD and CTSD were de-termined by duplicated film method and used to analyse the behavior of mixed Ⅰ+Ⅱ elastic-plastic fracture in aluminium alloy Ly12, and then the relationship between COD and J-integral for differ-ent mixed ratios was also discussed. The results show that: (1) the mixed initiation CODi of Ly12 increases with the increase of mode Ⅱ component, and the CODi for pure mode Ⅱ loading is 6 times of CODi for puer mode Ⅰ loeding; (2) the COD and the J-integral under mixed loading satis-fy the relation of JM=dσ0COD, where d is a coefficient which varies with mixed ratios, as well as materials, and is determined by testing and calculating.

关 键 词：复合型 COD 弹塑性断裂 J积分 断裂力学 

分 类 号：O346.1[理学—固体力学]