摘要
对Ti-6Al-4V钛合金冷挤压紧固结构件进行试验和理论研究。由断口金相数据得到选定裂纹参考尺寸下的裂纹萌生时间(TTCI)分布,基于裂纹扩展方程,通过改变参考裂纹尺寸和当量初始缺陷尺寸(EIFS)的上界进行优化得到表征原始疲劳质量的当量初始缺陷尺寸(EIFS)分布,确定当量初始缺陷尺寸额定值。以概率断裂力学耐久性分析方法得到可靠度95%和选定经济修理极限下的经济修理寿命,从而为冷挤压工艺用于结构紧固件强化的经济修理提供理论依据。
In this paper, experimental and analytical studies were conducted on the Ti-6Al-4V cold expanded fas- tener hole. The distribution of crack initiation life was determined by metallographic fracture data. Based on the crack growth formula, the equivalent initial flaw size which characterized the initial fatigue quality was obtained by optimizing the reference crack size and the upper limit of equivalent initial flaw size. The rated equivalent initial flaw size was then determined. Referring to a designated economic repair size, the economic repair life with the re- liability of 95% was obtained using the theory of probabilistie fracture mechanics. This work provided a theoretical guidance on the economic repair of structures containing cold expanded holes.
出处
《机械科学与技术》
CSCD
北大核心
2012年第10期1601-1604,共4页
Mechanical Science and Technology for Aerospace Engineering
基金
高等学校学科创新引智计划项目(B07050)
先进设计与智能计算省部共建教育部重点实验室开放课题项目(AD-IC2010007)资助
关键词
钛合金
原始疲劳质量
裂纹萌生时间
当量初始缺陷尺寸
概率断裂力学
titanium alloy
initial fatigue quality
equivalent initial flaw size （EIFS）
probabilistic fracture me- chanics approach
