Analysing the influences of weld size on fatigue life prediction of FCAW cruciform joints by strain energy concept

The effect of weld size on fatigue life of flux cored arc welded (FCAW) cruciform joints containing lack of penetration (LOP) defect has been analysed by using the strain energy density factor (SEDF) concept. Moreover, new fracture mechanics equations have been developed to predict the fatigue life of the cruciform joints. Load carrying cruciform joints were fabricated from ASTM 517 'F' grade steel. Fatigue crack growth experiments were carried out in a vertical pulsar (SCHENCK 200 kN capacity) with a frequency of 30 Hz under a constant amplitude loading (R = O). It was found that the crack growth rates were relatively lower in the larger welds fabricated by the multipass welding technique than the smaller welds fabricated by the single pass welding technique.