钛合金典型结构细节原始疲劳质量分析  

Analysis of Initial Fatigue Quality for Representative Structure Detail of TC4

作　　者：刘潇然 孙秦[2] LIU Xiaoran;SUN Qin(School of Aeronautical Engineering,Zhengzhou University of Aeronautics,Zhengzhou 450046,China;School of Aeronautics,Northwestern Polytechnical University,Xi′an 710072,China)

机构地区：[1]郑州航空工业管理学院航空工程学院,郑州450046 [2]西北工业大学航空学院,西安710072

出　　处：《机械科学与技术》2021年第5期816-820,共5页Mechanical Science and Technology for Aerospace Engineering

基　　金：国家自然科学基金项目(51375386)。

摘　　要：针对飞机结构中常用的钛合金典型结构细节,采用原始疲劳质量方法对其耐久性进行了分析。首先完成了钛合金典型结构细节在3个应力水平下的耐久性试验,通过疲劳断口判读补充了小裂纹扩展数据集,统计获得了各应力水平下的裂纹形成时间TTCI及通用当量初始缺陷尺寸EIFS的概率分布及特征参数。在此基础上,预测了典型结构细节95%可靠度疲劳寿命,并基于EIFS分布预测了95%可靠度的当量初始裂纹尺寸,结果表明该钛合金典型结构细节满足设计要求。For the representative structure detail of titanium alloy applied in aeronautical engineering structure,the durability is analyzed by using the initial fatigue quality method.The durability tests of the representative structure detail of titanium alloy under 3 stress levels are performed on Instron8802 test machine.The crack growth data of the representative structure detail is obtained by analyzing the fracture via electron microscope.The probabilistic characteristics for the time of crack initiation(TTCI)and equivalent initial flaw size(EIFS)are achieved with the statistical analysis of test data.Then,the 95%reliability fatigue life is predicted via initial fatigue quality method.Besides,the 95%reliability EIFS is also calculated based on EIFS distribution.Results show that the representative structure detail of titanium alloy meets the requirement of durability design.

关 键 词：钛合金 原始疲劳质量 耐久性 裂纹形成时间 当量初始缺陷尺寸 

分 类 号：V215.5[航空宇航科学与技术—航空宇航推进理论与工程]