北京航空航天大学学报 ›› 2013, Vol. 39 ›› Issue (9): 1218-1221,1227.

• 论文 • 上一篇    下一篇

航空铝合金弹塑性状态疲劳裂纹扩展速率试验

张纪奎1, 吴烈苏1, 马少俊2, 刘建中2   

  1. 1. 北京航空航天大学 航空科学与工程学院, 北京 100191;
    2. 北京航空材料研究院, 北京 100095
  • 收稿日期:2012-10-22 出版日期:2013-09-30 发布日期:2013-10-13
  • 作者简介:张纪奎(1979-),男,陕西大荔人,讲师,zjk@buaa.edu.cn.
  • 基金资助:

    国家自然科学青年基金资助项目(50903002)

Experimental studies on fatigue crack growth rate at elastic-plastic state of aeronautical aluminum alloy

Zhang Jikui1, Wu Liesu1, Ma Shaojun2, Liu Jianzhong2   

  1. 1. School of Aeronautic Science and Engineering, Beijing University of Aeronautics and Astronautics, Beijing 100191, China;
    2. Beijing Institute of Aeronautical Materials, Beijing 100095, China
  • Received:2012-10-22 Online:2013-09-30 Published:2013-10-13

摘要: 研究含长裂纹薄壁结构弹塑性状态下的裂纹扩展规律对于保证机体结构安全具有重要意义.设计了民机用铝合金大宽板裂纹扩展速率测试用试验件和夹具,进行了2024-T3和7075-T6两种铝合金大宽板弹塑性状态下裂纹扩展速率测试.讨论了应力强度因子变程(ΔK)和裂纹中心线处的张开位移变程(Δδ)作为弹塑性状态下裂纹扩展速率表征参量的适用性.研究结果表明:中、高级应力水平作用下,含长裂纹铝合金大宽板裂纹进入快速扩展阶段,裂纹扩展ΔK~da/dN曲线发生明显转折,不能用Paris公式拟合.在裂纹扩展后期,Δδ~da/dN曲线在双对数坐标下呈线性关系,可用Δδ~da/dN关系曲线来表征弹塑性状态下铝合金的裂纹扩展速率.

Abstract: Studying the crack propagation behavior of the thin-walled structure with long cracks is very significant for ensuring the safety of the airframe. The specimen and fixture of aluminum alloy wide plate was designed for fatigue crack propagation rate (da/dN) testing. The fatigue crack growth rate was tested for 2024-T3 and 7075-T6 aluminum alloy at elastic-plastic state. The relationship between the range of stress intensity factor (ΔK) or crack central line displacement (Δδ) and da/dn was discussed to describe the crack propagation behavior of aluminum alloy. The experimental results show that under medium-high loading, the long crack of wide plate grows quickly; the da/dNK curve turns obviously at this stage; the crack growth behavior cannot be expressed as Paris law. At the final stage, there is a linear relationship between Δδ and da/dn in the logarithm coordinate. The crack propagation behavior of aluminum alloy at elastic-plastic could be described by Δδ~da/dN curve.

中图分类号: 


版权所有 © 《北京航空航天大学学报》编辑部
通讯地址:北京市海淀区学院路37号 北京航空航天大学学报编辑部 邮编:100191 E-mail:jbuaa@buaa.edu.cn
本系统由北京玛格泰克科技发展有限公司设计开发