制孔工艺对紧固孔疲劳性能的影响  

Effect of Drilling Processes on Fatigue Performance for Fasten Holes

作　　者：徐红炉[1] 刘军[1] 章刚[1] 岳珠峰[1] 

机构地区：[1]西北工业大学力学与土木建筑学院,陕西西安710072

出　　处：《飞机设计》2008年第3期25-30,共6页Aircraft Design

基　　金：国家自然科学基金项目(50375124;10472094);国家863计划项目(2007AA04Z404)

摘　　要：分别在传统制孔工艺和Winslow制孔工艺下,对7050T7351铝合金材料的双犬骨连接件疲劳试验结果进行对比与可靠性分析;基于当量初始裂纹(EIFS)理论和符合性判据,计算不同制孔工艺下的原始疲劳质量;采用体视显微镜和扫描电镜对疲劳断口进行分析;对Winslow制孔工艺强化机理进行了定性的探讨。研究表明:改进工艺后,紧固孔的疲劳寿命均有所提高,分散性降低,疲劳强度增加;紧固孔的当量初始裂纹小于0.125 mm,符合抗疲劳耐久性设计的要求;裂纹形核的位置不变,裂纹扩展区疲劳条带变窄。The fatigue experimental results of dog-bone mechanical joint for 7050T7351 aluminum alloy material are compared and the reliability analysis of fatigue life was carried out under the traditional and Winslow drilling processes in fastener holes. Based on the equivalent initial flaw size method and the eoineidenee criterion, the initial fatigue quality of two different drilling processes is calculated. Fatigue fractures are analyzed using stereomieroseope and scanning electron microscopy. The reasons that Winslow drilling process can improve the fatigue performance of fasten hole are discussed qualitatively. The results show that： With the Winslow drilling process, the fatigue life and the fatigue strength of fasten hole increases. At the same time the dispersibility decreases. Equivalent initial flaw size is smaller than 0. 125 millimeter that can meet the requirement of coincidence criterion, The location of crack nucleation is unchanged and fatigue striations become narrow at the crack extended area.

关 键 词：Winslow制孔工艺 疲劳寿命 细节疲劳额定值 原始疲劳质量 疲劳断口 

分 类 号：TH161.14[机械工程—机械制造及自动化]