碳辅助氢还原/碳化法制备纳米WC粉的烧结工艺研究  

Sintering Process of WC Nano-powders Prepared by Carbon-hydrogen Co-reduction and Carbonization Method

作　　者：卓海鸥 叶楠[2] 张金祥 刘文胜[2] 唐建成[3] ZHUO Haiou;YE Nan;ZHANG Jinxiang;LIU Wensheng;TANG Jiancheng(Ganzhou Nonferrous Metallurgy Research Institute, Ganzhou 341000, Jiangxi, China;Powder Metallurgy Research Institute of Central South University, Changsha 410083, Hunan, China;School of Materials Science and Engineering, Nanchang University, Nanchang 330031, Jiangxi, China)

机构地区：[1]赣州有色冶金研究所,江西赣州341000 [2]中南大学粉末冶金研究院,湖南长沙410083 [3]南昌大学材料科学与工程学院,江西南昌330031

出　　处：《中国钨业》2017年第4期44-50,共7页China Tungsten Industry

基　　金：国家自然科学基金资助项目(51364036,51471083);江西省博士后科研择优资助项目(2016KY11)

摘　　要：以碳辅助氢还原/碳化法制备的纳米WC粉为原料,采用低压烧结工艺制备超细晶WC-6Co硬质合金。采用XRD和SEM表征了烧结工艺对WC-Co烧结体的物相组成和显微形貌的影响,并测试了烧结体的力学性能。结果表明,随着烧结温度升高和时间延长,烧结体的致密度增加,晶粒尺寸增大,硬度和抗弯强度随着致密度增加而提高,但烧结温度过高或时间过长,会降低烧结体的性能。最佳烧结工艺为,烧结温度1 360°C,保温时间60 min,所得WC-6Co硬质合金的平均晶粒尺寸为305 nm,洛氏硬度和抗弯强度分别达到94.6 HRA和4 450 MPa。The WC nano-powders prepared by the carbon-hydrogen co-reduction and carbonization method were utilized as raw materials.The ultra-fine grained WC-6C0cemented carbides were obtained by sinter-HIP process.The phase composition and microstructure of WC-Co sintered bulk were characterized with XRD and SEM,respectively.And the mechanical properties of the sintered bulk were tested.The results show that the density and mean grain size of the sintered bulk increase as the sintering temperature and duration increase.The hardness and bending strength of the sintered bulk improve with the density increases.However,the mechanical performance would decline if the sintering temperature is excessively high or the duration is excessively long.The optimal sintering process parameter is the sintering temperature of1360°C with60min duration.Under the optimal process,the mean grain size of the WC-6C0cemented carbides is305nm,the hardness and bending strength are94.6HRA and4450MPa,respectively.

关 键 词：WC-CO 烧结工艺r显微组织 致密度 力学性能 

分 类 号：TF125.3[冶金工程—粉末冶金]