Effects of flux composition on the element transfer and mechanical properties of weld metal in submerged arc welding

• Published in: Metals and materials international Vol. 15; no. 3; pp. 471 - 477
• Main Authors: Bang, Kook-soo, Park, Chan, Jung, Hong-chul, Lee, Jong-bong
• Format: Journal Article
• Language: English
• Published: Springer The Korean Institute of Metals and Materials 01.06.2009; Springer Nature B.V; 대한금속·재료학회
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Engineering Thermodynamics; Flux; Heat and Mass Transfer; Machines; Magnetic Materials; Magnetism; Manganese; Manufacturing; Materials Science; Metallic Materials; Processes; Silicon; Slags; Solid Mechanics; Submerged arc welding; Titanium dioxide; Weld metal; Welding; Wire; 재료공학; flux; submerged arc welding; metal-cored wire; element transfer; weld metal mechanical properties
• ISSN: 1598-9623; 2005-4149
• DOI: 10.1007/s12540-009-0471-3

Submerged arc welding was performed using metal-cored wires and fluxes with different compositions. The effects of wire/flux combination on the chemical composition, tensile strength, and impact toughness of the weld metal were investigated and interpreted in terms of element transfer between the slag and the weld metal, i.e. , Δ quantity. Both carbon and manganese show negative Δ quantity in most combinations, indicating the transfer of the elements from the weld metal to the slag during welding. The amount of transfer, however, is different depending on the flux composition. More basic fluxes yield less negative Δ C and Δ Mn through the reduction of oxygen content in the weld metal and presumably higher Mn activity in the slag, respectively. The transfer of silicon, however, is influenced by Al 2 O 3 , TiO 2 and ZrO 2 contents in the flux. Δ Si becomes less negative and reaches a positive value of 0.044 as the oxides contents increase. This is because Al, Ti, and Zr could replace Si in the SiO 2 network, leaving more Si free to transfer from the slag to the weld metal. Accordingly, the Pcm index of weld metals calculated from chemical compositions varies from 0.153 to 0.196 depending on the wire/flux combination, and it almost has a linear relationship with the tensile strength of the weld metal.