用于铝合金车体外壳焊缝的疲劳设计图

为了开发疲劳强度设计图,作者对铝合金车体外壳焊缝进行疲劳试验。选用组成双层外壳的中空挤压型材焊缝和2种单层外壳补强焊缝作为车体外壳焊缝,通过对小尺寸和全尺寸试样的疲劳试验获得S-N曲线,采用统计处理方式,得出用于中空挤压型材焊缝的疲劳设计图。同样,用全尺寸试样开发了2种单层外壳补强焊缝通用的疲劳设计图。该图适用于评估焊缝附近材料应力范围内的疲劳强度。

Fatigue Design Diagram for Weld Joints on Aluminum Alloy Carbody Shells

In order to develop some fatigue design diagrams,the authors carried out weld joint fatigue tests for an aluminum alloy carbody shell.The hollow extrusion weld joints of a doubled-skinned and two types of reinforced weld joints of a single-skinned shell were selected as being representative of carbody shell weld joints.The authors created a fatigue design diagram for the hollow extrusion weld joints by means of a statistical treatment of an S-N curve obtained from the fatigue tests using both small-size and full-scale test specimens.In addition,they used the full-scale test specimens in the same manner to develop a common diagram for two kinds of reinforced welds used on single-skinned shells.The diagrams were valid for evaluating fatigue strength from the stress range of materials near the weld joints.