Nanoindentation investigation on the creep behavior of P92 steel weld joint after creep-fatigue loading

摘要

Using nanoindentation technology, the creep behavior of P92 steel welded joint that had experienced creep-fatigue (CF) loading was studied at the nanoscale. In both as-welded and CF samples, the fine-grain heat affected zone region exhibited relatively lower hardness and lower creep resistance than other regions of the welded joint. Compared to the as-welded sample, enhanced creep deformation and reduced hardness were observed in the CF sample. The strain rate sensitivity was in the range from 0.010 to 0.035 for as-welded sample and 0.052 to 0.082 for the CF sample, as the measurement region changed from base metal to weld metal regions.