Microstructures and mechanical properties of bonding layers between low carbon steel and alloy 625 processed by gas tungsten arc welding

• Published in: Metals and materials international Vol. 23; no. 6; pp. 1168 - 1175
• Main Authors: Lou, Shuai, Lee, Seul Bi, Nam, Dae-Geun, Choi, Yoon Suk
• Format: Journal Article
• Language: English
• Published: Seoul The Korean Institute of Metals and Materials 01.11.2017; Springer Nature B.V; 대한금속·재료학회
• Subjects: Base metal; Characterization and Evaluation of Materials; Chemistry and Materials Science; Dilution; Engineering Thermodynamics; Filler metals; Gas tungsten arc welding; Heat affected zone; Heat and Mass Transfer; Heat treating; Low carbon steels; Machines; Magnetic Materials; Magnetism; Manufacturing; Martensite; Materials Science; Mechanical properties; Metallic Materials; Metals; Processes; Research Paper; Solid Mechanics; Tensile properties; Welding parameters; Wire; 재료공학; alloys; welding; microstructure; scanning electron microscopy (SEM); mechanical properties
• ISSN: 1598-9623; 2005-4149
• DOI: 10.1007/s12540-017-7167-x

A filler metal wire, Alloy 625, was cladded on a plate of a low carbon streel, SS400, by gas tungsten arc welding, and the morphology of the weld bead and resulting dilution ratio were investigated under different welding parameter values (the input current, weld speed and wire feed speed). The wire feed speed was found to be most influential in controlling the dilution ratio of the weld bead, and seemed to limit the influence of other welding parameters. Two extreme welding conditions (with the minimum and maximum dilution ratios) were identified, and the corresponding microstructures, hardness and tensile properties near the bond line were compared between the two cases. The weld bead with the minimum dilution ratio showed superior hardness and tensile properties, while the formation lath martensite (due to relatively fast cooling) affected mechanical properties in the heat affected zone of the base metal with the maximum dilution ratio.