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Quantitative Analysis on the Effects of Welding Parameters on Diffusible Hydrogen Contents in Weld Metal Produced by FCAW Process

FCAW에서 용접금속 확산성수소량에 미치는 용접변수 영향의 정량적 해석

  • Received : 2009.11.23
  • Accepted : 2010.01.28
  • Published : 2010.04.30

Abstract

The effects of welding parameters such as contact tip-to-work distance (CTWD), voltage, and current on the weld metal diffusible hydrogen contents (HD) were investigated and rationalized by the calculation of heating time and amount of heat generated in the extension length of flux cored wire. As CTWD increased from 15 to 25mm, HD decreased from 8.46 to 5.45mL/100g deposited metal. Calculations showed that, with an increase of CTWD, the amount of heat generated increased from 46 to 92J in addition to an increase of heating time. Increase of current from 250 to 320A, however, gave little variation of HD. It showed that no significant change in the amount of heat generated was found, and heating time was decreased with an increase of current. It also showed that CTWD is more influential than voltage in relatively lower heat input ranges, while voltage is more in higher input ranges

Keywords

References

  1. M. Matsushita and S. Liu : Hydrogen control in weld metal by means of fluoride additions in welding flux, Welding Journal, 71-6 (2000), 295s-303s
  2. D. White, G. Pollard and R. Gee : The effect of welding parameters on diffusible hydrogen levels in cored wire welding, Welding & Metal Fabrication, 60-6 (1992), 209-216
  3. B. Dixon and K. Hakansson : Effects of welding parameters on weld zone toughness and hardness in 690MPa steel, Welding Journal, 74-4 (1995), 122s-132s
  4. D. D. Harwig, D. P. Longenecker and J. H. Cruz : Effects of welding parameters and electrode atmospheric exposure on the diffusible hydrogen content of gas shielded flux cored, Welding Journal, 78-9 (1999), 314s-321s
  5. J. H. Kiefer : Effects of moisture contamination and welding parameters on diffusible hydrogen, Welding Journal, 75-5 (1996), 155s-161s
  6. ANSI/AWS A4.3-86 : Standard methods for determination of diffusible hydrogen content of martensitic, bainitic, and ferritic weld metal produces by arc welding, American Welding Society, (1985)
  7. Miroslav Pitrun : The effect of welding parameters on levels of diffusible hydrogen in weld metal deposited using gas shielded rutile flux cored wires, Ph.D thesis, The University of Wollongong, (2004)