It is very important to evaluate fatigue crack growth in partial penetrated welded joints where the unwelded part can be regarded as a crack-line defect.
Fatigue crack growth tests were performed for base metals and transverse welding beads of two kinds of aluminum alloys, namely, 5083-H113 and 7039-T61, and also for a partial penetrated welded joint of 5083-H113 aluminum alloy. Through the tests fatigue crack closure behavior was monitored by the unloading elastic compliance technique using a personal computer system. Fatigue crack growth rates were well expressed by the effective stress intensity factor range based on crack closure measurements.
From the experiment's results, the fatigue crack growth behavior of partial penetrated welded joint is well predicted by the fatigue crack growth rates of transverse welded metal, taking into account the effective stress intensity factor range $ΔK_eff$.