Creep constitutive equations of P92 steel welded joint

The welding heat thermal cycle was simulated through the heat treating method, and the simulated microstructures of the coarse grain heat-affected zone(CGHAZ), fine grain heat-affected zone(FGHAZ) and intercritical heat-affected zone(ICHAZ) of P92 steel were prepared by using a furnace at 3.53 K/s of heating rate.The uniaxial creep data of the base metal, deposited metal and simulated CGHAZ, FGHAZ and ICHAZ specimens were obtained through the creep tests under the temperature of 923 K, and the creep constitutive equations of each material were obtained too.The result shows that the creep strain rate of FGHAZ is higher than the other zones of the welded joint under the low stress.So the creep rupture is easy to occur in the FGHAZ.In addition, the creep properties are obviously different among the CGHAZ, FGHAZ and ICHAZ, which indicate the HAZ has the obvious material heterogeneity.