PREPARATION OF IN SITU COMPOSITES BY EDGE-DEFINED, FILM-FED GROWTH (EFG) DIRECTIONAL SOLIDIFICATION.
A novel form of crystal growth called edge-defined, film-fed growth (EFG) has been applied to the directional solidification of Cu/ZrCu//3, CaF//2/LiF, Al//2O//3/ZrO//2 and Al//2O//3/UO//2 eutectic materials. This method allows the continuous solidification of eutectic materials as solid bodies having any constant cross-sectional shape. In particular, it is possible to grow filaments continuously, and lengths of Al//2O//3/UO//2 and Al//2O//3/ZrO//2 eutectic filaments, 10 mils in diameter and over 50 ft long have been produced. Such filaments have been found to show strengths in excess of 65,000 psi at 1620 degree C. There is no obstacle to the directional solidification of other shapes of constant cross section, such as ribbons or twisted ribbons which might be required for such applications as turbine blades.