Accession Number : ADD013667

Title :   Apparatus for Casting Directionally Solidified Articles.

Descriptive Note : Patent, Filed 14 Oct 86, patented 15 Dec 87,

Corporate Author : DEPARTMENT OF THE AIR FORCE WASHINGTON DC

Personal Author(s) : Sawyer, Thomas F

Report Date : 15 Dec 1987

Pagination or Media Count : 7

Abstract : A furnace assembly for casting directionally solidified articles, such as turbine blades. A pair of tunnels feed blanket insulative material towards the bottom of the heating chamber to engulf the mold as it exits the chamber atop a water cooled pull rod. It is therefore the primary object of the present invention to provide an improved furnace assembly for producing directionally solidified articles from eutectic superalloy compositions. The improved furnace assembly basically comprises a heating chamber of substantially cylindrical shape adapted to accept a mold. The bottom of the mold rests on a pull rod, and a susceptor of substantially cylindrical cross-section surrounds the mold and is spaced therefrom to permit a downward vertical movement of the mold. The exterior of the susceptor is surrounded by insulative material and an RF coil which inductively heats the susceptor. The pull rod provides a means for lowering the mold out of the heating zone and preferrably has a coolant fluid pumped therein to provide a chilling surface at the end of the pull rod in contact with the base of the mold. Positioned immediately below the bottom of the heating chamber and surrounding the pull rod are a pair of diametrically opposed tunnels having plunger means at the distant ends thereof for forcing a blanket type alumina insulation material against the mold as it exits the bottom of the furnace. The blanket insulation envelops the mold and forms a continuous heat barrier around the mold as it descends out of the heating chamber of the furnace assembly whereby lateral heat transfer is prevented.

Descriptors :   *SUPERALLOYS, *GAS TURBINE BLADES, *CASTING, *PATENTS, BARRIERS, BOTTOM, COMPOSITION(PROPERTY), COOLANTS, CROSS SECTIONS, CYLINDRICAL BODIES, EUTECTICS, FLUIDS, FURNACES, HEAT, INSULATION, MOLDS(FORMS), PUMPING, RADIOFREQUENCY, SHAPE, VERTICAL ORIENTATION, WATER COOLING, NICKEL, COBALT, IRON

Subject Categories : Properties of Metals and Alloys
      Hydraulic and Pneumatic Equipment

Distribution Statement : APPROVED FOR PUBLIC RELEASE