摘要
本文以LY12CZ铝合金缺口薄壁试验件为研究对象,首先进行了有限元分析,得到了相应的K_T,并插值得到S-N曲线;然后创新性地提出了一个在工程中较为方便应用的等效应力的公式,根据此公式计算得到的等效应力对传统的名义应力法进行了改进。最后对缺口试验件进行了五级常幅多轴加载试验。缺口多轴疲劳试验证明,采用本文中的改进的名义应力法计算的缺口多轴寿命具有较高的准确度,试验寿命和预测寿命误差均处于两倍误差带范围之内。
In this paper,the LY12 CZ aluminum is selected.First,the finite element model is set up,and the numerical simulation is conducted,and then the stress concentration factor is obtained by the existing S-N curve through curve fitting.This paper proposed an innovative formula of equivalent stress,which can use in engineering more convenient.Based on the formula of equivalent stress,the traditional nominal stress method is improved.Then the multiaxial notch experiment is done,using five grades of proportional or non-proportional multiaxial loading.The experiment result showed that,the multiaxial notch fatigue life prediction,which uses the modified traditional nominal stress method of this paper,has a high accuracy,and the predicted results show good agreement with experimental results.
出处
《飞机设计》
2015年第4期41-46,60,共7页
Aircraft Design
基金
航空基金(2011ZA52016)
关键词
缺口
多轴疲劳
寿命预测
notch
multiaxial fatigue
life prediction
