纳米WC-Co复合粉末的制备及性能分析

Preparation and Properties Analysis of Nano WC-Co Composite Powders

采用机械合金化的方法制备了纳米WC-Co粉末,并利用X射线衍射、透射电镜以及扫描电镜等对粉末进行分析。结果表明：经过不同时间球磨后粉末尺寸和形状发生了明显的变化。随着球磨时间的延长,晶粒尺寸不断下降,球磨50 h晶粒粒度达到16 nm,物相中除有少量W2C相以外没有其它杂质相存在,制备的粉末纯度较高,分布较均匀;随着时间的延长,粉末形状从部分呈较大的片层多棱角状不规则结构到层状结构不明显的小颗粒,颗粒呈规则圆滑的近球形,粉末不断细化,粒度分布在纳米级较窄范围内。

Nano-sized WC-Co powders were prepared by mechanical alloying. The powder was analyzed by X-ray diffraction, transmission electron microscope and scanning electron microscope. The results show that, after different time ball milling, the size and shape of powder change obviously. With the prolongation of ball milling time, the grain size decreases,and the grain size reaches 16 nm after 50 h ball milling. There is no impurity phase except a small amount of W2 C phase. The prepared powder has high purity and is uniformly distributed. As time goes on, the shape of the powder changes from partial large lamellar polygonal irregular structure to small particles with out obvious lamellar structure, and the particles are regular,smooth and nearly spherical, the powder is finer, and the particle size is in narrow range of nanometer level.