双周疲劳载荷作用下焊接接头线性累计损伤分析  

Linear cumulative damage analysis of welded joints under combined cycle fatigue

作　　者：张涛[1] 王东坡[1] 邓彩艳[1] 吴良晨[1] 

机构地区：[1]天津大学材料科学与工程学院,天津300072

出　　处：《焊接学报》2014年第3期61-65,116,共5页Transactions of The China Welding Institution

基　　金：国家自然科学基金资助项目(51275343;51375331)

摘　　要：采用自制的超声频分量双周疲劳(CCF)试验装置,对16Mn的焊接接头试件进行低频疲劳载荷与超声频分量(高频)载荷复合加载,采用线性累计损伤理论来估算双周疲劳载荷作用下16Mn对接接头的疲劳寿命,并计算两个疲劳载荷分量各自造成的累计损伤比例.结果表明,使用Miner法则计算双周疲劳试件的疲劳累积损伤时,如果高低周疲劳载荷只是简单按照比例计算,会严重低估两个分量疲劳载荷之间的耦合作用;而低周疲劳载荷按外包络线计算的方法则能够很好的考虑到高低周疲劳载荷间的耦合作用.16Mn steel welded joints are tested to fail under low cycle fatigue,high cycle fatigue and combined cycle fatigue using an apparatus that is capable of providing interactive loading. A linear cumulative damage theory is used to estimate the fatigue life of the butt joints. The proportion of each of the two fatigue load components which cause the cumulative damage is calculated. The research indicate that high cycle fatigue loads and low cycle fatigue loads simply calculated as proportion would seriously underestimate the coupling between the two components of the fatigue load when we use Miner rule to calculate the fatigue cumulative damage of specimens. However,we can take into account of the coupling between the high and low cycle fatigue loads when we turn to the outsourcing envelope of the low cycle fatigue loads.

关 键 词：焊接接头 双周疲劳 线性累积 

分 类 号：TG404[金属学及工艺—焊接]