Stress state of dissimilar welded joints tensile loaded in creep conditions
The difference in the creep rates of the dissimilar metals in their fusion zone results in a strain constraint which leads to the formation of a heterogeneous stress state in the areas in the vicinity of the interface.
The normal stresses reach the maximum in the central part of the fusion zone, and the tangential stresses and the stress intensity are maximum at the periphery of the zone. The level of the maximum stresses is higher than the corresponding nominal stresses.
The area and nature of failure of the dissimilar welded joints in the creep conditions show that the formation of cracks is caused by the deviator components of the stress state τxy and σi whose magnitude can be determined from Eqs. (17) and (18).
The local stresses in the fusion zone depend on the creep factor and increase with a reduction in its value.
KeywordsStress State Stress Intensity Normal Stress Maximum Stress Creep Rate
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