Quantitative characterization on fatigue fracture features of A6005 aluminum alloy welded joints

Fatigue performance is important for materials and welded joints in engineering structures. A fatigue test of A6005 aluminum alloy welded joints was conducted. When confidence level was 50%, fatigue lives were reliable for reliability levels of 50% and 97.7%. Statistical F-test evaluation proved that the linear fatigue stress-life model was rational. Metallic oxides or discrete barlike materials led to crack nucleation. Fractal dimension characterized the fracture features, initially increased and then decreased at all stress levels. However, crack propagation rates were inversely proportional to fractal dimension. Further, fractal dimension integration equalled the fatigue life. A linear relationship was established with a good R2 obtained 0.978.

Automated summary

Fatigue performance is crucial for materials and welded joints in engineering structures. The study on A6005 aluminum alloy welded joints revealed that the linear fatigue stress-life model was rational, and the presence of metallic oxides or discrete barlike materials could lead to crack nucleation.