A study of the high‐pressure transformation in iron using an opposed‐anvil x‐ray diffraction apparatus and high‐pressure light metallography has shown that the 130‐kbar transformation is martensitic. The bcc and hcp phases were found to coexist over a large pressure range, and there is a large hysteresis between the forward and reverse transformation‐start pressures. A room‐temperature equilibrium pressure for the bcc and hcp phases of 107 ± 8 kbar is proposed, and discrepancies in the current P‐T equilibrium diagram for iron are discussed.
REFERENCES
1.
D.
Bancroft
, E. L.
Peterson
, and S.
Minshall
, J. Appl. Phys.
27
, 291
(1956
).2.
3.
4.
5.
R. L.
Clendenen
and H. G.
Drickamer
, J. Phys. Chem. Solids
25
, 865
(1964
).6.
H.
Mao
, W. A.
Bassett
, and T.
Takahashi
, J. Appl. Phys.
38
, 272
(1967
).7.
8.
9.
10.
P. M. Giles and M. H. Longenbach, Proceedings of the Second Annual Meeting of the International Metallographic Society, 1969, p. 111.
11.
C. E. Weir, A. VanValkenberg, and E. Lippincott, in Modern Very High Pressure Techniques, edited by R. H. Wentdorf (Butterworths, Washington, D.C., 1962), p. 51. p. 51.
12.
T.
Takahashi
, W. A.
Bassett
, and H. K.
Mao
, J. Geophys. Res.
73
, 4717
(1968
).13.
J. C. Jamieson in discussion of a paper by E. V. Clougherty and L. Kaufman, in High Pressure Measurements, edited by A. A. Giardini and E. C. Lloyd (Butterworths, Washington, D.C., 1963), p. 165.
14.
15.
16.
A. VanValkenberg, in High Pressure Measurements, edited by A. A. Giardini and E. C. Lloyd (Butterworths, Washington, D.C., 1963), p. 87.
17.
18.
L. Kaufman and M. Cohen, in Progress in Metal Physics, edited by B. Chalmers and R. King (Pergammon, London, 1958), Vol. 7, p. 165.
19.
L. D.
Blackburn
, L.
Kaufman
, and M.
Cohen
, Acta Met.
13
, 533
(1965
).20.
P. C.
Johnson
, B. A.
Stein
, and R. S.
Davis
, J. Appl. Phys.
33
, 557
(1962
).21.
22.
G. C. Kennedy and R. C. Newton, in Solids Under pressure, edited W. Paul and D. M. Warshauer (McGraw‐Hill, New York, 1962), p. 463.
23.
24.
E. V. Clougherty and L. Kaufman, in High Pressure Measurements, edited by A. A. Giardini and E. C. Lloyd (Butterworths, Washington, 1963), p. 152.
25.
This content is only available via PDF.
© 1971 The American Institute of Physics.
1971
The American Institute of Physics
You do not currently have access to this content.