B_4C粉末的滚动球磨、振动球磨和气流粉碎

Ball Milling,Vibratory Milling and Jet Milling of Boron Carbide Powders

用碳管炉硼酸碳热还原法制备了平均粒度为 2 3 6 μm的原始B4 C粗粉 ,并分别用滚动球磨、振动球磨和气流粉碎 3种不同的粉碎工艺制取了B4 C细粉 ,研究了它们的粉碎效率、粉碎机理和粉碎动力学。结果表明 ,B4 C粉末的滚动球磨以表面粉碎为主 ,因而粉碎效率低 ;而振动球磨以体积粉碎为主 ,所以粉碎效率高 ;气流粉碎的粉碎机理以体积粉碎为主 ,表面粉碎也有一定的作用 ,因此 ,粉碎效率介于滚动球磨和振动球磨之间。滚动球磨和振动球磨均使B4 C粉末残留较多的杂质Fe 。

Boron carbide powders with a average particle size of 23 6μm prepared by reducing boric acid with carbon in a carbon tube furnace was comminuted by ball milling,vibratory milling and jet milling respectively Comminution efficiency,comminution mechanism and comminution kinetics of B 4C powder were studied The experimental results indicate that ball milling process has the minimal comminution efficiency with the main comminution mechanism of surface grinding However vibratory milling has the maximum comminution efficiency with the dominant mechanism of volume smash Jet milling has a medium efficiency resulting from both mechanisms of volume smash(main) and surface grinding In addition,high content of ferrite impurity remained in B 4C powder by ball milling and vibratory milling process,but hardly any impurity could be examined in jet milled powders