Microstructural Evolution and Mechanical Properties of FCAW Joints in 9% Ni Steel Prepared with Two Types of Ni-Based Weld Metals

The microstructural and mechanical evaluation of 9% Ni steel with flux-cored arc welding (FCAW) was performed two different Ni-based weld metals: Inconel 625 Hastelloy 609. metals showed changes depending on the temperature gradient crystal growth rate for each region during cooling after welding. A cellular/planar exhibited at bottom metal, which rapidly cooled in contact cold base metal. Columnar dendrites were central that relatively slowly, precipitates observed interdendritic region. joints between metal have a compositional transition due to dilution. comprised martensite layer γ-phase layer, according distribution. In low-temperature toughness test, absorbed impact energies 89 55 J 609, respectively. When is used as compared high content γ-stabilizer start decreasing elements leads formation thicker thinner addition, these suppresses transformation maintains stability joint interface even low temperatures, resulting higher energy. microstructure its influences properties help improve practical application FCAW.