The establishing of the susceptability of the fusion metal of austenitic submerged arc weld deposits to crack formation

The susceptability of the fusion metal of fully austenitic submerged arc weld deposits and - by comparison - of that of submerged arc weld deposits containing delta ferrite, having various chemical compositions, to the formation of cracks as the result of hot tensile testing during the course of a simulated welding temperature cycle. The results obtained indicated the thermal crack resistant effect of the delta ferrite as well as the beneficial effects of increased manganese and molybdenum contents. By means of photo-optical and raster screen electron microscopic methods it was possible to demonstrate that the orientation boundaries of cells were the most likely place for cracks to form and that liquid phases were the cause. The results obtained were also applied to actual multiple pass welds. (orig.)