Factors affecting creep damage accumulation and mechanical properties of 316 stainless steel weldments.

摘要

he creep deformation and mechanical properties of 316 stainless steel weldments with E316 and E1682 filler metals (316W and 16-8-2 welds, respectively) were studied. Three related studies were carried out in this dissertation.;In Part A, the mechanical property degradation of 316 weldments due to creep and thermal aging was studied. Oversize specimens with two welds inside the gage length were creep tested at 650;The difference in creep strength between the base metal and welds produced a multiaxial stress state around the weld after creep. The multiaxial stress distributions in oversize weldments were simulated by the finite element method. Three stress parameters were used to correlate the multiaxial stresses with creep damage distributions. Metallographic examination showed that the principal facet stress parameter gave the best prediction of the creep damage distribution produced by the multiaxial stress state. This is covered in Part B.;Part C focuses on the effect of solidification microstructures on the mechanical and creep properties of 316 welds. Factors affecting the deformation anisotropy of welds were studied. Columnar grains with