Abstract
The objective of this study, based on the concept of fitness-for-purpose, is to evaluate the fracture toughness in X-grooved weld HAZ(heat-affected zone) of QLT(quenching, lamellarizing and tempering)-processed 9% Ni steel, qualitatively and quantitatively, and analyze the relation between the fracture toughness and microstructure. In general, CTOD test is widely used to determine the fracture toughness of steel weldments. But several problems of accuracy have been brought up. To avoid those, in this paper, modified CTOD testing method is proposed and used for weld HAZ for 9% Ni steel. In addition, microstructure of HAZ is observed and analyzed by OM, SEM and XRD.
From the results, HAZ toughness of QLT-9% Ni steel decreased as the evaluated region approaches the fusion line from base metal. The decrease in toughness was apparently partly caused by the reduction of the retained austenite content resulting from the decrease in nucleation sites for α→γ reverse transformation due to the increasing fraction of coarse-grained region. On the other hand, due to the poor stability of retained austenite in the mixed zone of weld metal/base metal, toughness drop in F. L.~F. L.+3mm was larger than that in F. L.+5mm and F.L.+7mm with decreasing test temperature.
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References
H.T. Tamura, G. Onzawa, and S. Uematsu, J Japanese Welding Soc., 49: 854 (1980)
E.F. Nippes and J.P. Balaguer, Welding Journal, 65:237-s (1986)
Consortium of five Japanese company, GRI report,GRI. 86–0007 (1986)
British Standard BS 5762 (1979)
British Standard BS 7448 (1991)
ASTM Standard E 1290 (1989)
S.J. Squrrel, H.G. Pisarski, and M.G. Dawes, BSIISM/4/4, Working Party Report (1986)
ASTM E24 Committee, Draft ASTM Test Standard for Fracture Toughness Testing of Weldments, ASTM E24. 06. 05. (1991)
M. Toyoda, IIW Doc., X-1217–91 (1991)
H.G. Pisarski and M.G. Dawes, Measurement of COD in Weldment with Particular Reference to Offshore Structures, 111 (1980)
ASTM standard E1304 (1989)
K. Kajimoto, M. Tani, and N. Ikutoh, Quartely J. Japanese Welding Soc., 4: 182 (1983)
K. Arimochi, M. Nakanishi, S. Satoh, F. Minami, M. Toyoda and K. Satoh, J. Japanese Welding Soc., 52: 148 (1983)
F. Minami, M. Toyoda, C. Thaulow and M. hauge, Quarterly.l. ofJapanese Welding Soc., 13: 508 (1995)
API RP 2Z, “Recommended Practice for Preproduction Qualification for Steel Plates for Offshore Structures” (1987)
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© 1998 Springer Science+Business Media New York
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Jang, J., Yang, Y., Kim, W., Kwon, D. (1998). A Study of Fracture Toughness and Microstructures in the Weld Heat-Affected Zone of QLT-Processed 9% Ni Steel. In: Balachandran, U.B., Gubser, D.G., Hartwig, K.T., Reed, R.P., Warnes, W.H., Bardos, V.A. (eds) Advances in Cryogenic Engineering Materials . Advances in Cryogenic Engineering, vol 44. Springer, Boston, MA. https://doi.org/10.1007/978-1-4757-9056-6_6
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DOI: https://doi.org/10.1007/978-1-4757-9056-6_6
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