Abstract
In order to examine the difference between the sensitivity of Charpy absorbed energy, VE, and critical CTOD, δcr, to strength mismatch in welds, the numerical analysis was conducted. This study adopted the evaluation method based on the Weibull stress criterion for calculation of VE and δcr assuming that the critical Weibull stress at brittle fracture is independent of the strength mismatch as well as the loading rate. This analysis showed that the VE and δcr decreased as the location of the V-notch or crack approached welded interface. The change in VE was larger than that in δcr, because the strength mismatch caused acceleration of strain rate and decrease in temperature rise near the V-notch as well as plastic constraint. This result indicates that the sensitivity of the VE and δcr to strength mismatch is different depending on the loading rate.
