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Engineering topics

Griesenauer, N. M.

Publications and source records attributed to Griesenauer, N. M..

Undercooling of materials during solidification in space

The theoretical and actual effect of undercooling on molten materials below the equilibrium solid us temperature was studied. Materials in the categories of pure metals, alloys, and compounds were examined: their commercial and scientific value and past experience in their undercooling were considered. The material properties influencing undercooling behavior are reviewed, specified, and categorized. The effects of gravity and its absence are investigated. It is shown that presence of heterogeneous nucleating agents is the main obstacle to achieving a large degree of undercooling.

Moak, D. P.↗

Single crystals of metal solid solutions

The following definitions were sought in the research on single crystals of metal solid solutions: (1) the influence of convection and/or gravity present during crystallization on the substructure of a metal solid solution; (2) the influence of a magnetic field applied during crystallization on the substructure of a metal solid solution; and (3) requirements for a space flight experiment to verify the results. Growth conditions for the selected silver-zinc alloy system are described, along with pertinent technical and experimental details of the project.

Miller, J. F.↗