摘要
以偏钨酸铵、醋酸钴、裂解碳为原料，配置成料浆，通过喷雾干燥-氢气还原碳化（简称直接碳化法）和喷雾干燥-氮气煅烧-氢气还原碳化（简称煅烧-碳化法）制备WC—Co复合粉。对两种工艺制备粉末的性能和形貌进行对比，发现直接碳化法制备的WC—Co复合粉的颗粒在10-100wm、平均粒度在50μm，大部分球形壳破裂，粉末仍然保持球形骨架，粉末松装密度小、流动性差；煅烧-碳化法制备的WC—Co复合粉末的颗粒度在10-50μm、平均颗粒度25μm，粉末球形度高、流动性好。将两种工艺制备的粉末制成YG6合金，对比发现直接碳化法得到WC—Co复合粉制备成的硬质合金硬度高、晶粒度小、密度高、孔隙度低、致密度高；将两种工艺制备的粉末进行热喷涂，发现煅烧-碳化法制备的粉末热喷涂时，涂层表面致密度高、WC保留率高、硬度高。
Using ammonium metatungstate, cobalt acetate, pyrolysis carbon as raw materials, configurating them into slurry, WC-Co composite powder was prepared by spray drying-hydrogen reduction ＆ carbonization method （referred to as direct carbonization method） and spray drying-nitrogen calcination-hydrogen reduction ＆ carbonization method （referred to as calcinations-carbonation method）. The property and morphology of powder prepared by the two methods were compared. Results show that WC-Co composite powder prepared by direct carbonation method has a particle size range of 10-100 μm,its average particle size is about 50 Ixm, most of powder spherical shell cracks, powder remains spherical shape, the bulk density is low, and the fluidity is poor. WC-Co composite powder prepared by calcinations-carbonation method has a particle size range of 10~50 Ixm, its average particle size is about 25 Ixm, the powder sphericity is high, and the fluidity is good. YG6 Cemented carbide produced by WC-Co composite powder prepared by direct carbonation method is of high hardness, small grain size, high density, low porosity and good compactness. The powder prepared by calcinations- carbonation method is used for thermal spraying, the coating surface is of high density, high WC retention rate and high hardness.
出处
《硬质合金》
CAS
2014年第2期77-85,共9页
Cemented Carbides
基金
国家国际科技合作专项(2011DFR50970)
国家863计划项目(2012AA061902)
国家自然科学基金(51174101)
湖南省科技重大专项(2012FJ1009)
江西省钨与稀土重大科技专项(2010AZD00100)
江西省高等学校科技落地计划项目(KJLD12072)
关键词
喷雾转换法
直接碳化法
煅烧-碳化法
WC—Co复合粉
硬质合金
热喷涂
spray conversion
direct carbonization method
calcinations-carbonization method
WC-Co composite powder
, cemented carbide
thermal spraying
