Creep property of the Hastelloy X weld metals obtained by filler metals with minor elements.

To improve the creep property of Hastelloy X TIG welded joints, some filler metals were developed with addition of several minor elements, such as, boron, rare earth metals and zirconium. The weld metals and weld joints obtained by the developed filler metals were subjected to the uniaxial creep testing at 900°C. Some of them showed excellent creep strength and rupture ductility. Among of the additions in the filler metals, boron was most effective for improvement of creep property, rare earth metal fairly effective, but zirconium little effective. Filler metals selected by the uniaxial creep testing were applied to weld the cylindrical specimens circumferentially and longitudinally, the weld metals were subjected to the creep testing with internal pressure at 900°C to investigates the integrities of the welded structure. As a result, the creep rupture life of some welded cylinders was longer than that of non-welded cylinder.