Accession Number : AD0818427

Title :   FIBER REINFORCED NI-CR ALLOYS FOR HIGH TEMPERATURE-HIGH STRENGTH APPLICATIONS.

Descriptive Note : Final rept. 1 Jul 65-30 Nov 66,

Corporate Author : TYCO LABS INC WALTHAM MA

Personal Author(s) : Bates, Herbert E. ; Wald, Fritz ; Weinstein, Martin

Report Date : JAN 1967

Pagination or Media Count : 93

Abstract : The object of this program was to investigate the factors involved in the preparation of fiber-reinforced Ni-Cr alloys by controlled precipitation from the melt. The mechanical properties of Ni-Cr matrix composites prepared by controlled solidification were also studied. Preparation of fiber-reinforced composite structures by controlled precipitation in situ of the reinforcing phase has several inherent advantages over such methods as liquid infiltration or thermomechanical processes. Problems of wetting, compatibility, and fiber distribution are essentially already solved in a workable system. Thus, if the reinforcing phase precipitates from the liquid, it can be expected to be chemically stable in the solid. The precipitation process ensures an interface between fiber and matrix which is strongly adherent, and the solidification kinetics tend to produce a regular array of precipitates of a size and spacing which is dependent on the solidification rate. The Ni-Cr matrix was selected for its high temperature strength, ductility, and oxidation resistance, while Cr3C2 was a desirable reinforcing phase on the basis of its high strength and modulus, relatively low density, and anisotropic growth habit. (Author)

Descriptors :   *CHROMIUM ALLOYS), *SOLID SOLUTIONS), *DISPERSION HARDENING), (*NICKEL ALLOYS, (*REINFORCING MATERIALS, (*CARBIDES, HARDNESS, SILICONES, DUCTILITY, MECHANICAL PROPERTIES, TENSILE PROPERTIES, ELONGATION, OXIDATION, DENSITY, SOLUBILITY, SHEAR STRESSES, STRENGTH(PHYSIOLOGY), COMPOSITE MATERIALS, ANISOTROPY, HIGH TEMPERATURE, ETCHING, ELECTRON MICROSCOPY, X RAY DIFFRACTION, WHISKERS(CRYSTALS).

Subject Categories : Laminates and Composite Materials
      Fabrication Metallurgy

Distribution Statement : APPROVED FOR PUBLIC RELEASE