【摘要】 采用2.45GHz高功率多模腔微波炉制备WC8Co硬质合金,对压坯的收缩率和合金的显微组织进行研究。结果表明:液相温度出现在1300°C附近;在烧结温度1450°C下保温5min能获得几乎全致密的合金试样。微波烧结法制备的合金晶粒要比真空烧结制备的合金晶粒尺寸细小且分布更均匀。另外,WC晶粒的尺寸和分布主要取决于烧结温度;保温时间对合金晶粒的影响很小,无论在1450°C下保温多长时间WC平均晶粒的尺寸始终保持在2.7μm。更多还原

【Abstract】 WC 8Co cemented carbide samples were processed via microwave irradiation in a 2.45 GHz, high-power multi-mode microwave cavity. The densification of the compacts and the microstructures of the prepared alloys were studied. The results demonstrate that the liquid phase is formed around 1300 °C and nearly full densification is obtained at 1450 °C for 5 min via microwave irradiation. The microstructures of microwave sintered samples have finer and more uniform WC grains than those of vacuum sintered samples. Besides, the WC grain size and distribution are only decided by the sintering temperature. Holding time has negligible effects on them. No matter how holding time is, the mean grain size is 2.7μm when the sintering temperature is kept at 1450 °C.更多还原