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Welding in the World

, Volume 61, Issue 6, pp 1275–1285 | Cite as

Mechanisms of weld pool flow and slag formation location in cold metal transfer (CMT) gas metal arc welding (GMAW)

  • Md. R . U. Ahsan
  • Muralimohan Cheepu
  • Rouholah Ashiri
  • Tae-Hoon Kim
  • Chanyoung Jeong
  • Yeong -Do Park
Research Paper
  • 548 Downloads

Abstract

This work investigates the weld pool flow behavior by observing the flow pattern of floating slag particles for cold metal transfer (CMT) gas metal arc welding (GMAW) using three different welding wires. These wires contain different amount of deoxidizers in the form of silicon and manganese. In situ high-speed videography shows that for the wire containing a high amount of deoxidizer, the weld pool flows from the center towards the toe. With the presence of a lower amount of deoxidizers, it flows from the toe towards the center. Besides, a higher amount of CO2 in the shielding gas changes the amount and location of slag formation. Chemical composition analysis of weld metals relates the weld pool flow behavior with the amount of dissolved oxygen (surface active element). The presence of adequate amount of oxygen in the weld pool can alter the weld pool flow pattern, which changes with the amount of deoxidizers present in the materials and the amount of oxygen supplied through the shielding gas. Based on this concept, the mechanisms involved in weld pool flow pattern and slag formation location for different composition of the consumables are disclosed to improve weld quality and productivity through the selection of the proper welding consumables in CMT-GMAW.

Keywords (IIW Thesaurus)

Marangoni convection Surface active elements Flow visualization Slag Cold metal transfer (CMT) Gas metal arc welding (GMAW) 

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Copyright information

© International Institute of Welding 2017
corrected publication August 2017

Authors and Affiliations

  • Md. R . U. Ahsan
    • 1
    • 2
  • Muralimohan Cheepu
    • 3
  • Rouholah Ashiri
    • 2
    • 4
  • Tae-Hoon Kim
    • 5
  • Chanyoung Jeong
    • 2
  • Yeong -Do Park
    • 2
    • 3
  1. 1.Department of Mechanical EngineeringInternational University of Business, Agriculture and TechnologyDhakaBangladesh
  2. 2.Department of Advanced Materials EngineeringDong-Eui UniversityBusanRepublic of Korea
  3. 3.Department of Advanced Materials and Industrial Management EngineeringDong-Eui UniversityBusanRepublic of Korea
  4. 4.Department of Materials EngineeringIsfahan University of TechnologyIsfahanIran
  5. 5.R&D Center, Kiswel Co. LtdChangwonRepublic of Korea

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