The Reaction Spray Process (RSP) offers the opportunity to synthesize fine-grained, multicomponent, pre-alloyed tungsten based powders in one step. These powders allow sintering to full density far below the melting temperature of the binder phase. Compared to the conventional process of mechanical mixing arid subequent liquid phase sintering of powder mixtures where the powder particle size and the rapid grain growth during sintering restricts the lower limit of the W-grainsize, the RSP-powders lead to an extremely fine grained micro-structure. The W-grainsize can be varied in a wide range by variation of the sintering parameters. According to the Hall-Fetch-Equation the yield strength of the as-sintered components increases with decreasing W-grainsize. Due to the typical microstructure of solid state sintered tungsten heavy alloys with polygonal W-grains the contiguity of the W -phase is relative1y-high. Segregation of impurities at the W-W-boundaries leads to lower ductility of the as-sintered alloy. These negative influences of solid state sintering can be overcome by cold working of the sintered components. Variation of the percentage of the total area reduction and the final heat treatment allows the adjustment of the mechanical properties according to the requirement of different applications.
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