Creep failure prediction of brazing joints with double notches

摘要

This paper predicts the creep ductile failure of brazing joints with three different types of double notches by continuum damage mechanics simulation, and the effects of distance between the double notches (notch distance) and inside notch radius have been discussed. The results show that the different double notches have different creep failure lives and notch sensitivity effects due to the different notch strength ratios. For the notches in the surface of base metal and filler metal, the creep failure time decreases with the notch distance increases. Compared with single notch, the smaller notch distance shows a strengthening effect because of the larger notch strength ratio, otherwise it is a weakening effect. For the notches in the surface and center of filler metal, the creep failure time increases firstly then decreases with the increase of inside notch radius. Opposite to the notch distance effect, the smaller inside notch radius shows a weakening effect, while the bigger inside notch radius shows a strengthening effect. As the notch radius increases, the strengthening effect becomes not obvious. For the notches in the center of filler metal and the surface of base metal, the creep failure location moves from base metal to filler metal, and the failure time decreases with the increase of inside notch radius. The creep life of smaller inside notch radius is the same as single base notch, showing an insensitive effect. Nevertheless, it is a weakening effect for the bigger inside notch radius. (C) 2016 Elsevier Ltd. All rights reserved.