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Microwave sintering was explored in preparation of WC-8Co micro gears,which were formed by micro injection molding (μ-PIM).The micro gears were realized successfully with the addendum circle diameter ranging from 900 to 700 μm and with the center pole as small as 140 μm.The effects of microwave sintering temperature,holding time and sintering atmosphere on the density,hardness and microstructure of the prepared cemented carbide were studied to determine the optimum sintering conditions.It is found that the sintering temperature at 1400 and the holding time of 10 min are the b℃est process parameters,when the relative density of samples reached as high as 99.33%,hardness 91.5 HRA and average grain size 0.97 μm.In addition,the macroscopic properties and microstructure of the microwave sintered micro gears were compared with the conventional sintered samples.The results indicate that the values of the relative density and hardness of the microwave sintered gears are significantly higher than that of vacuum sintering at the same sintering temperature.The microstructure of the microwave sintered samples is also more uniform.