Accession Number : AD0631928

Title :   EFFECT OF FLUID FLOW ON SOLIDIFICATION STRUCTURE.

Descriptive Note : Technical rept.,

Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF METALLURGY

Personal Author(s) : Flemings,M. C. ; Utech,H. P. ; Miksch,E. S.

Report Date : MAR 1966

Pagination or Media Count : 73

Abstract : Samples of tellurium-doped indium antimonide that exhibited solute banding when solidified in a horizontal boat under ordinary conditions showed no bands when solidified in the presence of a vertical DC magnetic field. In crystal growth of tin, as of indium antimonide, marked thermal fluctuations occur in the liquid during growth as a result of thermal convection. Effects are examined here of growth parameters on these fluctuations. A dilute aluminum-copper alloy that exhibited solute banding when solidified in a horizontal crystal growing boat showed no bands when solidified in the presence of the magnetic field. The morphology and kinetics of ice grown in supercooled water are markedly affected by convection of the water. Brief consideration is given the problem of analysis of effect of fluid flow on dendritic growth in undercooled melts, employing the idealized 'Fisher dendrite'. The analysis is then extended to growth of dendrites in non-undercooled alloy melts and it is shown that similar effects are to be expected.

Descriptors :   (*CRYSTAL GROWTH, *FLUID FLOW), FREEZING, GRAIN STRUCTURES(METALLURGY), INDIUM ALLOYS, ANTIMONY, TIN, ALUMINUM ALLOYS, COPPER ALLOYS, ICE, MAGNETIC FIELDS, SUPERCOOLING, HEAT TRANSFER

Subject Categories : Metallurgy and Metallography
      Crystallography
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE