Reductions in reserves of qualitative raw material have made it necessary to search for new ways to recirculate metals from their wastes which form during production hard alloy products and in their use. In 1975, in Japan, a "WR Committee" was organized to develop a system for the processing and secondary use of hard alloys [1]. With this same goal in mind, a Secondary Tungsten Association was developed [2] in the USA in 1982. Since 1979 there have been regular international symposia dealing with tungsten. In capitalist countries about 52 percent of all the tungsten (in the USA it is over 60 percent) is used to produce hard alloys. For that reason, a large number of developments have been focused on ways to promote its recirculation [2]. They can be divided into two groups:
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