Tungsten/Kanthal composites containing 10, 20, 30, and 70 vol.%, 200 μm diameter GE 218 tungsten fibers were fabricated at NASA Lewis Research Center using the arc-spray method. The tapes containing unidirectional fibers were hot pressed at 1338K for 1 hour before being cooled to room temperature. Addition of tungsten fibers to the (Fe-Cr-Al) Kanthal alloy provides a composite with excellent strength for corrosion resistant, structural high temperature applications. However the mismatch in coefficients of thermal expansion between the Kanthal matrix (9.58 10~(-6) / K) and tungsten fibers (4.4 10~(-6) /K) generates strains. This paper contrasts results from neutron diffraction and crack compliance studies with preliminary results from numerical predictions by concentric cylinder and finite element models.
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