Co掺杂对粗颗粒、特粗颗粒WC粉末粒度与微观形貌的影响

以粗颗粒与特粗颗粒W粉为原料,研究了Co掺杂对粗颗粒与特粗颗粒WC粉末粒度与微观形貌的影响。结果表明,Co掺杂有利于WC粉末Fsss的提高与游离碳的降低,有利于得到单晶WC粉末。当Co掺杂量为w(Co)=0.035%时,WC粉末颗粒与晶粒形貌发生巨大变化,WC晶粒的结晶完整性明显改善,呈现明显的生长台阶与生长平面,但特粗颗粒WC粉末颗粒形貌的规则度较粗颗粒WC粉末的低。当碳化温度由1900℃提高到2000℃后,Co掺杂特粗WC颗粒表面出现大量WC纳米颗粒依附物。

Effect of Cobalt Adulterant on Particle Size and Microscopic Morphology of Coarse and Ultra Coarse Tungsten Carbide Powder

Effect of cobalt adulterant on the particle size and microscopic morphology of coarse and ultra coarse tungsten carbide powder is investigated,using coarse and ultra coarse tungsten powders as the starting materials. It is shown that,cobalt facilitates the increasement of Fisher Sub-Sieve Size (Fsss),the decreasement of free carbon of tungsten carbide powder as well as the formation of tungsten carbide single crystal. When the doping amount of cobalt is 0.035%,huge change in the microscopic morphology of the particle and grain of tungsten carbide takes place,and growing steps and growing planes can be easily identified. As a result,the crystalline perfection is improved. Nevertheless,the degree of the regulation in grain morphology of ultra coarse tungsten carbide particles decreases,compared with the one of coarse tungsten carbide. When the carburization temperature increases from 1 900 ℃ to 2 000 ℃,a lot of nano tungsten carbide particles adhered on the surface of cobalt-doped ultra coarse tungsten carbide are formed.