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ork has been carried out as a part of the Steam Generator Materials Project under the Nuclear R&D Program by MOST in Korea. REFERENCES 1. Y.S. Lim, J.H. Suh, I.H. Kuk, and J.S. Kim: Metall. Mater. Trans. A, 1997, vol. 28A, pp. 1223-31. 2. P.L. Threadgill and B. Wilshire: Met. Sci., 1974, vol. 8, pp. 117-24. 3. S.C. Srivastava and M.B. Ives: Corrosion, 1989, vol. 45, pp. 488-93. 4. W.W. Mullins and R.F. Sekerka: J. Appl. Phys., 1964, vol. 35, pp. 444-51. 5. B. Chalmers: Trans. AIME, 1954, vol. 200, pp. 519-32. 6. W. Primak, H. Howie, and R. Ward: J. Am. Chem. Soc., 1948, vol. 70, pp. 2043-46. 7. P. Hirsch, A. Howie, R.B. Nicholson, D.W. Pashley, and M.J. Whelan: Electron Microscopy of Thin Crystals, 2nd ed., Robert E. Krieger Publishing Co., New York, NY, 1977, pp. 357-65. 8. T. DebRoy and S.A. David: Rev. Modern Phys., 1995, vol. 67, pp. 85-112. 9. Binary Phase Diagram, 1st ed., T.B. Massalski, J.L. Murray, L.H. Bennett, H. Baker, and L. Kacprzak, eds., ASM, Metals Park, OH, 1986, vol. 2, p. 1529 (Mg-Ni) and p. 1751 (Ni-S). 10. L.M. Litz and J.L. Blocher: in High-Temperature Materials and Technology, I.E. Campbell and E.M. Sherwood, eds., John Wiley & Sons, Inc., New York, NY, 1967, pp. 431-54.

Effect of Growth Velocity on the Growth Temperature of the Al-AlxFe Eutectic in Al-2.85Fe-0.12V Alloy Y. WANG and H. JONES Binary Al-rich Al-Fe alloys exhibit several alternatives to the equilibrium Al-Al3Fe eutectic in their solidification microstructures. These include Al-Al6Fe, Al-AlmFe, and AlAlxFe eutectics, where Al6Fe, AlmFe, and AlxFe are metastable in the binary and can displace Al3Fe at increasing growth

Fig. 6—SEM micrographs showing the particle distributions in the CDSRs of (a) 600H and (b) 600L specimens. METALLURGICAL AND MATERIALS TRANSACTIONS A

Y. WANG, Postdoctoral Research Associate, and H. JONES, Professor, are with the Department of Engineering Materials, University of Sheffield, Sheffield S1 3JD, United Kingdom. Manuscript submitted August 10, 2000. VOLUME 32A, MAY 2001—1251

Table I. Measured Growth Temperature TG vs Growth Velocity V(␮m/s) for ␣Al-AlxFe Eutectic from the Present Work V, ␮m/s

100

200

300

340

510

710

TG1, ⬚C TG2, ⬚C

645.0 ⫾ 0.7 645.3 ⫾ 0.6

647.5 ⫾ 0.7 644.6 ⫾ 0.3

643.6 ⫾ 0.4 643.8 ⫾ 0.4

639.7 ⫾ 0.5 643.2 ⫾ 0.5

637.8 ⫾ 0.9 642.7 ⫾ 0.7

640.6 ⫾ 0.9 639.6 ⫾ 0.4

Note: TG1 is from the thermocouple nearest to the quenched front; and TG2 is from the more distant thermocouple. Each value tabulated is the mean of three separate measurements, and the standard deviation of these measurements is indicated.

Table II. Reported Values of Eutectic Temperatures TEU and Eutectic Growth Parameters BEU for Competing Eutectics in the Al-Fe and Related Systems From V Dependence of TG Eutectic

TEU , ⬚C

BEU , K (s/␮m)

1/2

Data for Comparison Reference

Al-Al3Fe

655.1 ⫾ 0.1

0.41 ⫾ 0.03

Liang and Jones[8]*

Al-Al6Fe

652.9 ⫾ 0.2

0.20 ⫾ 0.01

Liang and Jones[8]*

Al-AlxFe Al-Al11La3 Al-Al11Ce3 Al-Al3Ni Al-Al2Cu Al-Si

649.0 ⫾ 1.0 636.7 ⫾ 0.1 633.9 ⫾ 0.2 639.8 ⫾ 0.4 548.3 ⫾ 0.1 577.2

0.32