Accession Number : AD0781320

Title :   Directional Solidification of Ni3Cb Reinforced Eutectic Turbine Blades.

Descriptive Note : Final rept. 16 Mar 73-15 Mar 74,


Personal Author(s) : Curran,Patrick M. ; Erickson,John S.

Report Date : MAY 1974

Pagination or Media Count : 124

Abstract : The purpose of this program was to investigate the solidification processing techniques required to produce directionally solidified eutectics in turbine blade form for airfoils. Three directional solidification investment castings processes, namely, the modified Bridgman, commercial withdrawal and liquid metal cooling techniques were evaluated for casting eutectic turbine blades. It was determined that the liquid metal cooling process offered the highest temperature gradient capability of the three processes evaluated and therefore primary emphasis was placed on evaluating this solidification technique. Fully lamellar microstructures achieved in gamma prime + delta eutectic turbine blades made by the liquid metal cooling process exhibited creep rupture properties at 1800F equivalent to laboratory grown material, thereby establishing the viability of fabricating eutectic turbine blades by this method. A one dimensional heat transfer model was successfully used to indicate directions for improving process temperature gradient. (Modified author abstract)

Descriptors :   *Turbine blades, *Nickel alloys, *Niobium alloys, *Casting, Solidification, Eutectics, Airfoils, Cooling, Microstructure, Creep strength, Composite materials, Control, Fiber metallurgy, Heat resistant alloys, Directional, Aluminum alloys

Subject Categories : Properties of Metals and Alloys
      Jet and Gas Turbine Engines

Distribution Statement : APPROVED FOR PUBLIC RELEASE