微波烧结WC-Co硬质合金致密化与晶粒生长

Densification and grain growth of microwave sintered WC-Co cemented carbide

分别采用微波烧结和常规烧结制备WC-8Co硬质合金,通过1 000-1 400℃温度范围烧结以及1 400℃保温0-240 min的微波和常规烧结实验,测量各样品的收缩率、密度和晶粒尺寸,分析其致密化行为和晶粒生长,研究烧结温度和保温时间对合金致密化和晶粒生长的影响。结果表明,与常规烧结比较,微波烧结促进YG8硬质合金的致密化,且获得的合金组织均匀,晶粒细小。另外,保温时间对微波烧结YG8硬质合金的晶粒生长几乎没有影响。

Microwave and conventional technology were used to sintering WC-8Co cemented carbide.In order to research the effects of temperature and holding time on the densification and grain growth of the alloys,experiments with the temperature in range of 1 000-1 400 ℃,and the holding time in range of 0-240 min at 1 400 ℃ were conducted.The shrinkage,density and grain size of samples were systematically measured to analysis the densification behavior and the grain growth.The result shows that,in contrast to conventional sintering,microwave sintering enhances the densification behavior of WC-8Co alloys,and promotes homogeneous microstructure and finer grains.In addition,no evident influence of holding time on the grain growth of alloys sintered by microwave processing is observed.