The effects of weldment fatigue life improvement procedures are surveyed using an IP model computer simulation of weldment fatigue strength for a typical mild-steel structural weldment, a non-load-carrying cruciform weldment. The IP model combines estimates of crack initiation life or 'I' with the LEFM model estimates of the crack propagation life or 'P'. The life improvement strategies considered include: toe grinding, over stressing, weld profile improvement, and post-weld heat treatment. The effects of weldment fatigue life improvement procedures on the fatigue life of 'Nominal' and 'Ideal' weldments, that is, weldments with and without a 0.1 in. (2.5 mm) weld discontinuity at the weld toe, are compared. The 'Nominal' weldment is taken to be the appropriate paradigm when failure would be catastrophic or when one is forced to use standard welding procedures. The 'Ideal' weldment is suggested as an appropriate paradigm for manufacturers who have the goal of producing high-fatigue-performance weldments.
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