Determination of Creep Properties for P91 Weldment Materials at 625c

The work presented in this paper is related to the determination of the creep properties for a P91 pipe weldment at 625 C, which forms part of a collaborative European project (Weldon). A Kachanov type, one damage variable, multi-axial material behaviour model was used to represent the material creep behaviour. The uniaxial material constants for the parent material and weld metal were determined from conventional uniaxial creep test data, while the tri-axial stress state parameters for parent and weld materials were determined from the notched bar rupture test results. For the heat-affected zone (HAZ) material, the full set of material constants in the material behaviour model were determined from the results of impression creep tests of the HAZ material, in conjunction with the creep damage modelling of creep rupture tests of cross-weld specimens.