荷重伝達型片側すみ肉溶接継手における疲労き裂進展強度の解析的検討

抄録

Hydraulic excavators and cranes are major heavy equipment with numerous one-sided welded joints. Although fillet welded joints are easily implemented and economical, the unwelded portion frequently initiates crack propagation. Because of this problem, high evaluation method is needed for the unwelded area. In this study, the fatigue properties and the fracture mechanism of the load carrying type fillet joints with one-sided welding were investigated experimentally to evaluate its fatigue damage with high accuracy based on the experimental and analysis results. As the results, there was little crack start. Almost the all lifetime is crack propagation. Cracks were initiated at multiple sites in the test piece. As the number of cycles increased, these cracks propagated and combined, and we confirmed these behaviors using FEM analysis. In addition, because analysis crack propagation parameters are important, we performed CT test, and analyzed using acquired values. We found crack propagation parameter between standard values (wes2805-1) and tested values are different.