Weldability of 9Cr-ODS and JLF-1 Steels for Dissimilar Joining with Hot Isostatic Pressing and Electron Beam Welding

Dissimilar joints between 9Cr-ODS and JLF-1 were fabricated by hot isostatic pressing (HIP) and by electron beam welding (EBW), respectively. Compared to the HIP at 1000◦C, HIP at higher temperatures of 1050◦C and 1100◦C is effective to improve the joining strength of the joints. All the as-HIPed joints fractured at the interface during tensile tests. 1050◦C-HIP showed the best joining strength and reduction of area. Post-weld heat treatment (PWHT) with normalization and tempering (N&T) could further improve the joining properties of the HIPed joints. The joints fractured outside the interface at the JLF-1 base metals. EBW showed better weld-ability than HIP, because the joint made by EBW did not fracture at the weld metal during tensile tests, but always fractured at JLF-1 side. However, the properties of the HIPed joints were improved after PWHT with N&T, and were comparable to that made by EBW.