Abstract
The structure and mechanical properties of tempered martensite and lower bainite were investigated in a series of high purity 0.25 pct C steels with varying amounts of nickel and manganese. The martensites in 0.25 C-5 Ni−Fe and 0.25 C-3 Mn−Fe alloys were mainly untwinned, while those in 0.25 C-5 Ni-7 Mn−Fe and 0.25 C-7 Mn−Fe alloys were heavily twinned. Manganese appears to promote carbide precipitation along the lath boundaries in tempered martensite. At equivalent yield and ultimate tensile strength levels, the tempered martensite of lower manganese steels showed better impact toughness than the tempered martensite of higher manganese steels. The impact toughness (compared at similar strength levels) of untwinned tempered martensite of 0.25 pct C steel with Widmanstatten precipitation of carbide was higher than that of lower bainite, which showed unidirectional carbides. The reasons for the difference in impact toughness between the alloys, and also between the structures are rationalized in terms of internal twinning, grain boundary precipitation and carbide morphology together with other microstructural features.
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J. H. Holloman, L. D. Jaffe, D. E. McCarthy, and M. R. Norton:Trans. ASM, 1947, vol. 38, p. 807.
S. A. Herres and C. H. Lorig:Trans. ASM, 1948, vol. 40, p. 775.
W. T. Griffiths, L. B. Pfeil, and N. P. Allen:J. Iron Steel Inst., 1939, vol. 12, p. 343.
G. Sachs, L. J. Ebert, and W. F. Brown:Trans. AIME, 1948, vol. 176, p. 424.
E. F. Bailey:Trans. ASM, 1954, vol. 46, p. 830.
E. S. Davenport, E. L. Roff, and E. C. Bain:Trans. ASM, 1934, vol. 22, p. 289.
L. J. Klinger, W. J. Barnett, R. P. Frohmberg, and A. R. Troiano:Trans. ASM, 1954, vol. 46, p. 1557.
R. F. Hehemann, V. J. Luhan, and A. R. Troiano:Trans. ASM, 1957, vol. 49, p. 409.
B. J. Waterhouse: Spec. Rept. No. 93, 1965, p. 151, The Iron and Steel Institute, London.
K. J. Irvine and F. B. Pickering:J. Iron Steel Inst., 1963, vol. 201, p. 518.
J. S. Pascover and S. J. Matas: ASTM Spec. Tech. Publ. No. 370, 1963, p. 30.
Y. H. Liu:Trans. ASM, 1969, vol. 62, p. 55.
G. Thomas, D. Schmatz, and W. Gerberich:High Strength Materials, V. F. Zackay, ed., p. 324, John Wiley and Sons, New York, 1965.
P. M. Kelly and J. Nutting:J. Iron Steel Inst., 1961, vol. 197, p. 199.
S. Das and G. Thomas:Trans. ASM, 1969, vol. 62, p. 659.
R. L. Patterson and C. M. Wayman:Acta Met., 1964, vol. 12, p. 1306.
O. Johari and G. Thomas:Acta Met., 1965, vol. 13, p. 1211.
T. Boniszewski: Spec. Rept. No. 93, 1965, p. 22, The Iron and Steel Institute, London.
W. Jolley:J. Iron Steel Inst., 1968, vol. 206, p. 170.
W. Barr and A. J. K. Honeyman:J. Iron Steel Inst., 1947, vol. 157, p. 239.
J. Gorrissen:J. Iron Steel Inst., 1949, vol. 162, p. 16.
F. W. Bouger and R. H. Frazier:Trans. AIME, 1954, vol. 200, p. 645.
J. Heslop and N. J. Petch:Phil. Mag., 1957, vol. 2, p. 649.
R. F. Decker, J. T. Eash, and A. J. Goldman:Trans. ASM, 1962, vol. 55, p. 58.
W. R. Patterson and L. S. Richardson:Trans. ASM, 1966, vol. 59, p. 71.
P. Payson:Trans. AIME, 1954, vol. 200, p. 1242.
R. W. Messler, Jr., G. S. Ansell, and V. I. Lizvnov:Trans. ASM, 1969, vol. 62, p. 362.
S. Das and G. Thomas:Met. Trans., 1970, vol. 1, p. 325.
J. W. Christian: Spec. Rept. No. 93, 1965, p. 1, The Iron and Steel Institute, London.
E. Tekin and P. M. Kelly:Precipitation from Iron-Base Alloys, G. R. Speich and J. B. Clark, eds., p. 173, Gordon and Breach, New York, 1963.
P. M. Kelly and J. Nutting:Proc. Royal Soc., 1960, vol (A) 259, p. 45.
ASTM Proc., 1952, vol. 52, p. 543.
D. N. Shackleton and P. M. Kelly: Spec. Rept. No. 93, 1965, p. 126, The Iron and Steel Institute, London.
A. J. Baker, P. M. Kelly, and J. Nutting:Electron Microscopy and Strength of Crystals, G. Thomas and J. Washburn, eds., p. 899, Interscience, J. Wiley and Sons, New York, 1963.
F. B. Pickering: Symposium: Transformation and Hardenability in Steels, p. 109, Climax Molybdenum Co., 1967.
C. D. Beachem: U. S. Naval Res. Lab., Rept. of NRL Progress, January 1967, p. 28.
J. R. Low, Jr:Fracture, B. L. Averbachet al., eds., p. 68, M.I.T. Press, Cambridge, Mass., 1959.
A. R. Marder and G. Krauss:Trans. ASM, 1967, vol. 60, p. 651.
A. Gilbert, G. T. Hahn, C. N. Reid, and B. A. Wilcox:Acta Met., 1964, vol. 12, p. 754.
G. Krauss and W. Pitsch:Acta Met., 1964, vol. 12 p. 278.
M. Bevis, P. C. Rowlands, and A. F. Acton:Trans. TMS-AIME, 1968, vol. 242, p. 1555.
G. Thomas:Electron Microscopy Investigation of Martensite Formation and Substructure, AIME Symposium on Martensite, Las Vegas, May 1970, in press.
K. W. Andrews:J. Iron Steel Inst., 1965, vol. 203, p. 721.
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Huang, DH., Thomas, G. Structure and mechanical properties of tempered martensite and lower bainite in Fe−Ni−Mn−C steels. Metall Trans 2, 1587–1598 (1971). https://doi.org/10.1007/BF02913881
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DOI: https://doi.org/10.1007/BF02913881