Abstract
The behavior of the thermally stable austenite in the ductile fracture surface layer of a grain-refined and tempered 9Ni steel broken at 77 K was studied through use of Möss-bauer spectroscopy and transmission electron microscopy. Thin foils revealing the mi-crostructural profile of the fracture surface layer were prepared by electroplating a thick pure iron layer on the fresh fracture surface, then thinning a profile sample through a combination of conventional twin-jet electropolishing and ion milling techniques. The re-sults of both Mössbauer spectroscopy and TEM studies showed that the thermally stable austenite transforms to a dislocated martensite in the deformed zone adjacent to the duc-tile fracture surface. This result suggests that transformation of the retained austenite present in tempered 9Ni steel is compatible with low temperature toughness, at least when the transformation product is a ductile martensite.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
S. Nagashima, T. Ooka, S. Sekino, H. Mimura,T. Fujishima, S. Yno, and H. Sakurai:Trans. Iron Steel Inst. Japan, 1971, vol. 2, p.402.
T. Ooka, H. Mimura, S. Yano, K. Sugino, and T. Toizumi:J. Jap. Inst. Metals, 1966,vol. 30, p. 442.
C. W. Marshall, R. F. Heheman, and A. R. Troiano:Trans ASM, 1962, vol 55, p.135.
D. Hardwick:Iron Steel, 1961, vol. 34, p. 414.
C. A. Pampillo and H. W. Paxton:Met. Trans., 1972, vol. 3, p. 2895.
T. Ooka and K. Sugino:J. Jap. Inst. Metals, 1966, vol. 30, p. 435.
M. Kron, A. Constant, A. Clerc, J. Plateau, G. Henry, M. Robert, and C. Crussard: Mémoires Scientifiques Rev. Metallurg., 1961, vol. 58, p. 901.
H. Haga:Trans. Iron Steel Inst. Japan, 1973, vol. 13, p.141.
K. J. Kim and L. H. Schwartz:Mater. Sci. Eng., 1978, vol. 33, p. 5.
B. Fultz: unpublished results, Dept. Materials Science and Engineering, Uni-versity of California at Berkeley, Berkeley, CA, 1977.
C. K. Syn, S. Jin, and J. W. Morris, Jr.:Met. Trans. A, 1976, vol. 7A, p. 1827.
O. J. Klingenmaier:Modem Electroplating, 3rd ed., F. A. Lowenheim, ed., Chapter 10, John Wiley and Sons, New York, 1974.
See for example R. W.Hertzberg:Deformation and Fracture Mechanics of Engineering Materials, Chapter 8, John Wiley and Sons, New York, 1977.
K. R. Swanson and J. J. Spijkerman:J. Appl. Phys., 1970, vol. 41, p. 3155.
H. K. Chow, R. F. Weise, and P. A. Flinn: USAEC Report NSEC4023-1,1969.
L.H. Schwartz and K.J. Kim:Met. Trans. A, 1976, vol. 7A, p. 1567.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Syn, C.K., Fultz, B. & Morris, J.W. Mechanical stability of retained austenite in tempered 9Ni steel. Metall Trans A 9, 1635–1640 (1978). https://doi.org/10.1007/BF02661946
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF02661946