船用钢/铝爆炸焊过渡接头的疲劳试验

Fatigue Test of Ship Steel/Aluminum Explosive Welding Transition Joints

为了测试船用钢/铝爆炸焊过渡接头的疲劳性能,基于有限元方法,以钢/铝过渡接头为研究对象,重点研究过渡接头结合界面的疲劳强度,设计由3种材料组成的爆炸焊过渡接头试样,并结合数值仿真,对过渡接头试样在试验载荷下的受力进行分析,得到应力集中和容易疲劳失效的位置。结合试验研究,开展不同应力等级下过渡接头的疲劳试验,获取试样疲劳断裂数据,结合数值仿真和试验研究得到爆炸复合过渡接头整体应力分布和失效部位。通过疲劳试验发现试样断裂面均出现在铝合金和纯铝的界面处;通过试样疲劳循环次数拟合得到了名义应力的S-N曲线。该研究成果可用于指导船用爆炸复合结构的疲劳寿命预报,为船舶轻量化设计提供参考。

In order to test the fatigue performance of ship steel/aluminum explosive welding transition joints.Based on the finite element method(FEM),the steel/aluminum transition joint is taken as the research object,with a focus on the fatigue strength of the transition joint interface.An explosive welding transition joint specimen composed of three materials has been designed.And combined with numerical simulation,analyze the stress of the transition joint specimen under test load,and obtain the location of stress concentration and easy fatigue failure.Based on experimental research,fatigue tests were conducted on transition joints under different stress levels to obtain fatigue fracture data of the specimens.The overall stress distribution and failure location of the explosive composite transition joint were obtained through numerical simulation and experimental research.Through fatigue testing,it was found that the fracture surface of the specimen appeared at the interface between aluminum alloy and pure aluminum;the S-N curve of nominal stress was obtained by fitting the number of fatigue cycles of the specimen.This research result can be used to guide the fatigue life prediction of ship explosive composite structures and provide reference for lightweight design of ships.