Abstract
At temperatures below about 375 K, liquid-phase sintered tungsten base composites fail by cleavage of the tungsten spheroids. Alloying additions or heat treatments have not improved the ductility significantly. The ductilizing process described here consists in coating the composite with a ductile metal followed by heat treatment to insure sufficient diffusion for the coat and base to become integral. The ductile coat is now the “piece” surface, and the initiation of cleavage cracks requires much greater stresses. Coats of copper, nickel, gold and cobalt have been used successfully.
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This work performed under the auspices of the U.S. Energy Research and Development Administration.
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Zukas, E.G. Coating tungsten composites for improved low temperature ductility. Metall Trans B 7, 49–54 (1976). https://doi.org/10.1007/BF02652819
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DOI: https://doi.org/10.1007/BF02652819