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The effect of the morphology structure of tungsten oxide powders on the homogeneity of nanometer W/WC powder was studied during a conventional hydrogen reduction process. The properties of tungsten carbide powder and sintered WC-Co composites were characterized. It is shown that homogenous nanometer tungsten and tungsten carbide powders with loose and porous morphology structure can be prepared from fine tungsten oxide with loose and porous morphology structure. The grain aggregation and abnormal coarse grain are mainly due to the burning binding of agglomeration particle of nano tungsten powder during carbonization process