Composite single crystal article

1528637 Turbine blades UNITED TECHNOLOGIES CORP 19 Dec 1975 [23 Dec 1974] 52157/75 Heading F1T [Also in Division B3] A turbine blade 30 is produced by diffusion bonding (Division B3) of single crystal elements 31-34, 39, the elements having a maximum difference between their lattice parameters of 5% and the total maximum mismatch about the three orthogonal axes being less than 10 degrees, the core 31 (e.g. Co or Ni superalloys) exhibiting high strength at elevated temperatures and the face elements 32, 33 corrosion and oxidation resistance. One or more of the elements 31-34, 39 may be poly-crystalline and the core element 31 may consist of a ceramic body having a plurality of single crystal rods passing through the body bonded to the elements 34, 39. Air cooling channels 45, 46 are provided in the blade.