Characterization of Mechanical Properties in the Heat Affected Zones of Alloy 82/182 Dissimilar Metal Weld Joint

Alloy 82/182 이종금속 용접부 열영향부의 계계적물성치 파악

  • Published : 2008.12.31

Abstract

This paper presents the characteristics of mechanical properties within the heat affected zones(HAZs) of dissimilar metal weld joint between SA508 Gr.1a and F3l6 stainless steel(SS) with Alloy 82/182 filler metal. Tensile tests were performed using small-size specimens taken from the heat affected regions close to both fusion lines of weld, and the micro-structures were examined using optical microscope(OM) and transmission microscope(TEM). The results showed that significant gradients of the yield stress(YS), ultimate tensile stress(UTS), and elongations were observed within the HAZ of SA508 Gr.1a. This was attributed to the different microstructures within the HAZ developed during the welding process. In the HAZ of F316 SS, however, the welding effect dominated the YS and elongation rather than UTS. TEM micrographs demonstrated these characteristics of the HAZ of F316 SS was associated with a dislocation-induced strain hardening.

Keywords

heat affected zone;dissimilar metal weld;alloy 82/182;mechanical properties

References

  1. J.W. Kim, J.H. Lee, J.S. Kim, and T.E. Jin, "Evaluation of Local Tensile Properties of Dissimilar Metal Weld Joint at Ambient and Operating Temperatures", Proc. of KNS spring meeting, 2007
  2. J.W. Kim, J.S. Kim, K.S. Lee, and T.S. Byun, "Local mechanical properties of Alloy 82/182 dissimilar weld joint between SA508 Gr.1a and F316 SS at RT and $320^{\circ}C$", J. of Nucl. Materials, submitted, 2008
  3. T.S. Byun and K. Farrell, "Temperature dependence of strain hardening and plastic instability behaviors in austenitic stainless steels", Acta Materialia, Vol. 52, pp. 1597-1608, 2004 https://doi.org/10.1016/j.actamat.2003.12.023
  4. USNRC, "Information Notice 2000-17, "Crack in weld area of reactor coolant system hot leg piping at V.C. summer", Oct.18, 2000
  5. C. Jang, J. Lee, J.S. Kim, and T.E. Jin, "Mechanical property variation within Inconel 82/182 dissimilar metal weld between low alloy steel and 316 stainless steel", Int J. of Pres Vess. & Piping, Vol. 85, pp. 635-641, 2008 https://doi.org/10.1016/j.ijpvp.2007.08.004
  6. A. Celik, A. Alsaran, "Mechanical and structural properties of similar and dissimilar steel joints," Mater. Characterization", Mater. Characterization, Vol. 43, pp. 311-318, 1999 https://doi.org/10.1016/S1044-5803(99)00045-5
  7. M. Sireesha, S.K. Albert, V. Shankar, and S. Sundaresan, "A comparative evaluation of welding consumables for dissimilar welds between 316LN austenitic stainless steel and Alloy 800", J. of Nucl. Materials, Vol. 279, pp. 65-76, 2000 https://doi.org/10.1016/S0022-3115(99)00275-5
  8. A. Laukkanen, P. Nevasmaa, U. Ehrnsten, R. Rintamaa, "Characteristics relevant to ductile failure of bimetallic welds and evaluation of transferability of fracture properties", Nucl. Eng. & Design, Vol. 237, pp. 1-15, 2007 https://doi.org/10.1016/j.nucengdes.2006.03.022
  9. R. Stoenescu, R. Schaeublin, D. Gavillet, N. Baluc, "Mechanical properties-microstructure correlation in neutron irradiated heat-affected zones of austenitic stainless steels", J. of Nucl. Materials, Vol. 362, pp. 287-292, 2007 https://doi.org/10.1016/j.jnucmat.2007.01.251
  10. J. I. Bennetch, G. E. Modzelewski, L. L. Spain, and G. V. Rao, "Root cause evaluation and repair of alloy 82/182 J-groove weld cracking of reactor pressure vessel head penetrations at North Anna Unit 2", PVP-Vol. 437, ASME 2002, P.S. Lam, ed., ASME, New York, pp. 179-185, 2002
  11. W.D. Callister, Jr., "Materials Science and Engineering: An Introduction", 6th ed., John Wiley & Sons, Inc., 2003