Fatigue properties and fracture mechanism of load carrying type fillet joints with one-sided welding
Journal Title: Frattura ed Integrità Strutturale - Year 2016, Vol 10, Issue 35
Abstract
The structures of the hydraulic excavator and the crane have numerous one-sided welded joints. However, attachments with box like structures are difficult to weld at both sides. Therefore, high accurate evaluation method is needed. 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 results. As the results, fatigue cracks in the test piece initiated from the tip of the unwelded portion and propagated into the welding materials. Multiple welding defects were observed in the unwelded portion, but did not appear to be crack origins. Although these welding defects affected the direction of crack propagation they exerted minimal influence. The three-dimensional observations revealed that fatigue cracks initiate at an early stage of the fatigue development. We infer that the fatigue lifetime is chiefly governed by the crack propagation lifetime. Cracks were initiated at multiple sites in the test piece. As the number of cycles increased, these cracks propagated and combined. So considering the combination of cracks from multiple crack origins is important for a precise evaluation of fatigue damage.
Authors and Affiliations
Takamasa Abe, Hiroyuki Akebono, Masahiko Kato, Atsushi Sugeta
Keywords
Related Articles
- EP ID EP106777
- DOI 10.3221/IGF-ESIS.35.48
- Views 49
- Downloads 0
Effects of large amounts of hydrogen on the fatigue crack growth behavior of torsional prestrained carbon steel
The effects of large amounts of hydrogen on the fatigue crack growth properties of torsional prestrained ferritic–pearlitic low-carbon steel were investigated. Hydrogen-precharged specimens were produced by c...
Crack mode and life of Ti-6Al-4V under multiaxial low cycle fatigue
This paper studies multiaxial low cycle fatigue crack mode and failure life of Ti-6Al-4V. Stress controlled fatigue tests were carried out using a hollow cylinder specimen under multiaxial loadings of λ=0, 0.4,&nb...
Research on borehole stability of shale based on seepage-stress-damage coupling model
In oil drilling, one of the most complicated problems is borehole stability of shale. Based on the theory of continuum damage mechanics, a modified Mohr-Coulomb failure criterion according to plastic damage evoluti...
Implementation of a damage model in a finite element program for computation of structures under dynamic loading
This work is a numerical simulation of nonlinear problems of the damage process and fracture of quasi-brittle materials especially concrete. In this study, we model the macroscopic behavior of concrete material,...
Some relationships between the peak stresses and the local strain energy density for cracks subjected to mixed-mode (I+II) loading
In this work, a link between the averaged strain energy density (SED) approach and the peak stress method in the case of cracks subjected to mixed mode (I+II) loading has been investigated. Some closed-form expre...