Creep behavior and microstructural damage of martensitic P92 steel weldment

Creep rupture and creep crack growth of the heat-affected zones (HAZs) of P92(9Cr–2W) steel weldment are compared with those of base metal. From metallurgical investigation, creep cavities were observed at intercritical HAZs. The strain rate of the HAZ was faster than that of the base metal. The crack growth rate of the HAZ was faster than that of base metal. In the creep rupture test, the failure part was the intercritical HAZ but, in the creep crack growth test, the crack grew along the coarse-grained HAZ region of the fusion line.