A Study on Corrosion Properties of welded Alloy 625 for Ship Structure by Shielding Gases Composite Ratio

선체 구조용 Alloy 625의 용접시 보호가스 조성비에 따른 부식특성에 관한 연구

  • 안재필 (부경대학교 대학원 기계공학부) ;
  • 박경동 (부경대학교 기계공학부)
  • Published : 2005.05.01

Abstract

Alloy 625 is used widely in industrial applications such as aeronautical aerospace, chemical, petrochemical and marine applications. Because of a good combination of yield strength. tensile strength, creep strength, excellent fabricability, weldability and good resistance to high temperature corrosion on prolonged exposure to aggressive environments. High qualify weldments for this material are readily produced by commonly used processes. But all of processes are not applicable to this material by reason of unavailability of matching, position or suitable welding filler metals and fluxes may limit the choice of welding processes. Recently, the flux cored wire is developed and applied for the better productivity in several welding position including the vortical position. In this study. the weldability and weldment characteristics of Alloy 625 are evaluated in FCAW weld associated with the several shielding gases($80\%Ar+20\%\;CO_2,\;50\%Ar+50\%\;CO_2.\;100\%\;CO_2$) in viewpoint of welding productivity. The results of the experimental study on corrosive characteristics of Alloy 625 are as follows; There is no remarkable difference among shielding gases. however they has a striking difference among corrosive solutions by results of distinguished density and time of corrosive solution. Generally, the shielding gases($80\%Ar+20\%\;CO_2$) was superior to the other gases on high temperature tensile and a low temperature impact. but all of the shield gases were making satisfactory results on corrosion test.

Keywords

References

  1. The ASM International Handbook Committee. 'Heat-Resistant Materials', ASM International, pp. 222-225. 1997
  2. C. T. Sims et al, Superalloy II. John Wiley & Sons, pp.3-26. 97-133. 165-188. 1987
  3. M. McLean, High -Temperature structure materials, Chapman & Hall, pp 1-15, 1996
  4. Hujita, Sibata, 'A Role of Metallic Element for Ni-Base Alloy', The japan institute of Metals, Vol. 16, No. 4, pp331-339, 1977
  5. 대한용접학회. 용접. 접합 편람, pp.3-45, 203-241, 1998
  6. M. J. Cieslak, T. J. Headley and R. B. Frank, 'The Welding Metallurgy of Custom Age 625 PLUS Alloy', Welding Journal, Vol, 68, No. 12. pp 473-482, 1989
  7. M. J. Cieslak, 'The Welding and Solidification Metallurgy of Alloy 625', Welding Journal, Vol. 70, No. 2, pp.49-56, 1991
  8. J. N. Dupont, 'Solidification and Welding Metallurgy of Experimental Ni Base and Fe Base Alloys Containing Nb, Si and C', Ph.D. Thesis Lehigh University, pp6-12, 1997
  9. 정호신, '용융용접의 기초와 실제(II)-아크용접용의 보호가스,' 대한용접학회, 제12권 제2호, pp138-141. 2001
  10. D. A. Jones. Principle and Prevention of Corrosion, Prentice Hall, New Jersey, 1996
  11. D. Choi and G. S. Was, 'Corrosion,' Vol 46 , pp100, 1990