The development of macrostructure in ingots of increasing size

Springer Science and Business Media LLC - Tập 1 - Trang 1407-1412 - 1970
R. Morando1, H. Biloni1, G. S. Cole2, G. F. Bulling2
1Department of Metallurgy, Atomic Energy Commission, Buenos Aires, Argentina
2Ford Motor Co., Dearborn

Tóm tắt

A series of Al-Cu ingots ranging in volume from approximately 50 to 500 and to 5000 cc has been conventionally prepared in two ways, by normal chill casting or by using a magnetic field to control the convective currents. Comparisons allow us to differentiate among the various mechanisms proposed for the origin of equiaxed grains and for the columnar-to-equiaxed transition in castings: i) In normal casting, with the natural convection associated with standard superheats, the majority of grains is provided by the mechanism suggested by Chalmers (and also known as the Big Bang), or by crystal settling from a free surface as suggested by Southin. ii) If new grains, no matter how they may form, are inhibited from mixing with the rest of the liquid, no significant equiaxed structure appears. iii) Unless some special or preselected conditions prevail, other mechanisms such as those involving constitutional supercooling or dendrite remelting, do not seem operative in the formation of a central equiaxed zone.

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Tài liệu tham khảo

J. L. Walker: Liquids Metals and Solidification, ASM Seminar, 1958, p. 319.

R. W. Ruddle:The Solidification of Casting, Inst. of Metals, 1957.

W. C. Winegard:An Introduction to the Solidification of Metals, Inst. of Metals, 1964.

B. Chalmers:Principles of Solidification, John Wiley & Sons, New York, 1964.

Iron and Steel Inst. Publ. No. 110, London; The Brighton Conference, 1967.

T. F. Bower and M. C. Flemings:Trans. TMS-AIME, 1967, vol. 239, p. 216.

H. Biloni and R. Morando:Trans. TMS-AIME, 1968, vol. 242, p. 1121.

D. Walton and B. Chalmers:Trans. TMS-AIME, 1959, vol. 215, p. 447.

W. C. Winegard and B. Chalmers:Trans. ASM, 1954, vol. 46, p. 1214.

B. Chalmers:J. Australian Inst. Metals, 1963, vol. 8, p. 255.

K. A. Jackson, J. D. Hunt, D. R. Uhlmann, T. P. Sward, III:Trans. TMS-AIME, 1966, vol. 236, p. 149.

S. O’Hara and W. A. Tiller:Trans. TMS-AIME, 1967, vol. 239, p. 497.

R. T. Southin:Trans. TMS-AIME, 1967, vol. 239, p. 220.

G. S. Cole and G. F. Boiling:Trans. TMS-AIME, 1965, vol. 233, p. 1568.

G. S. Cole and G. F. Bolling:Trans. TMS-AIME, 1967, vol. 239, p. 1824.

D. R. Uhlmann, T. P. Seward, III, and B. Chalmers:Trans. TMS-AIME, 1966, vol. 236, p. 527.

H. Biloni and B. Chalmers:Trans. TMS-AIME, 1965, vol. 233, p. 373.

H. Biloni and B. Chalmers:J. Mater. Sci., 1968, vol. 3, p. 139.

J. A. Spittle, R. W. Smith, and G. W. Delamore: Iron and Steel Inst. Publ. No. 110, 1967, p. 138.

G. S. Cole and G. F. Boiling: Iron and Steel Inst. Publ. No. 110, 1967, p. 323.

G.S. Cole and G. F. Boiling:Trans. TMS-AIME, 1969, vol. 245, p. 725.

G. S. Cole and W. C. Winegard:J. Inst. Metals, 1964-65, vol. 93, p. 153.

H. Biloni and R. Morando: U.S. Army Contract DA-HC-19-68-G-0014; Report No. 3, March 1969.

S. Wojciechowski and B. Chalmers:Trans. TMS-AIME, 1968, vol. 242, p. 690.

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