Letter | Published:

Change of Length during Transformation of Iron under Stress


IT is well known1 that various metallic materials are mechanically weak while being transformed into another allotropic modification. We measured the change of length of specimens of pure iron2 while the metal, kept under tensile stress, was heated through the transformation temperature at 910° C. In Fig. 1 the change of length for fine-grained iron has been plotted for one α–γ transformation, one γ–α transformation and for a complete α–γ–α cycle as a function of stress. The resultant strain for the complete cycle gives a straight line through the origin. The fine-grained material for these experiments was obtained by loading the iron with a small amount (0.008 per cent by weight) of nitrogen3. All measurements were made in vacuo. An iron–carbon alloy containing 0.2 per cent by weight of carbon behaves in essentially the same way when given a temperature cycle through the two-phase field α + γ.

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  1. 1

    Sauveur, A., Iron Age, 113, 581 (1924). Scheil, E., Z. anorg. allg. Chem., 207, 21 (1932). Wassermann, G., Arch. Eisenhüttenw., 6, 347 (1933); 10, 321 (1937); 11, 89 (1937).

  2. 2

    Fast, J. D., and Luteyn, A. I., Philips Tech. Rev., 15, 73 (1949).

  3. 3

    de Jong, M., and Rathenau, G. W., Acta Metall., 5, 679 (1957).

  4. 4

    Bibring, H., and Sebilleau, F., C.R. Acad. Sci., Paris, 244, 1496 (1957).

  5. 5

    Basinski, Z. S., and Hume-Rothery, W., Proc. Roy. Soc., A, 229, 459 (1955).

  6. 6

    Lehr, P., C.R. Acad. Sci., Paris, 242, 1172 (1956).

  7. 7

    Bowles, J. S., and Barrett, C. S., “Progress in Metal Physics”, 3, 2 (London, 1952).

  8. 8

    Wechsler, M. S., Liebermann, D. S., and Read, T. A., Trans. Amer. Inst. Min. Met. Eng., 197, 1503 (1953). Chang, L. C., and Read, T. A., ibid., 189, 47 (1951). Burkart, M. W., and Read, T. A., ibid., 197, 1516 (1953).

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