抄録
Recently, some welded joints are designed to require a partial joint penetration part for the purpose of optimal design. So, it is very important to evaluate the fatigue crack initiation life at the root of partial joint penetration area. In the present study, the fatigue life prediction for such a welded joint was investigated by paying attention to the crack initiation at the root of partial joint penetration area using compact tension type specimens extracted from the partial joint penetration part of thick plates.
The experimental results indicated that the stress ration (R) and the root gap (Gap) did not affect the fatigue crack initiation life of welded joints with partial joint penetration in the range of 0<R≤0.75, 0≤Gap≤1.5mm. It means that the short fatigue cracks growing from the root of partial joint penetration area do not close in the loading range of this study.
From an engineering point of view, the fatigue crack initiation life of welded joints with partial joint penetration can be estimated by the linear fracture mechanics analysis based on the effective range of stress intensity factor.
