初始WC粉末对超细硬质合金组织与性能的影响  

Effect of Initial WC Powder on Microstructure and Properties of Ultra-Fine Cemented Carbide

作　　者：赖林 张佩 曾瑞霖 Lai Lin;Zhang Pei;Zeng Ruiling(State Key Laboratory of Cemented Carbide,Zhuzhou Hunan 412000,China;Zhuzhou Cemented Carbide Group Co.,Ltd,Zhuzhou Hunan 412000,China)

机构地区：[1]硬质合金国家重点实验室,湖南株洲412000 [2]株洲硬质合金集团有限公司,湖南株洲412000

出　　处：《硬质合金》2023年第6期443-449,共7页Cemented Carbides

基　　金：湖南省制造业关键产品“揭榜挂帅”项目(2022GXGG016);湖南省十大技术攻关项目(2021GK1170)。

摘　　要：采用3种粒度分布特征存在差异的同类型WC原料粉末,通过不同球磨时间、不同烧结温度制备了WC-4%Co-0.4%Cr_(3)C_(2)合金,研究了合金微观组织结构及性能的变化。研究结果表明,采用粒度集中的WC粉末原料更易于获得WC分布均匀、晶粒尺寸均匀的超细硬质合金;当WC原料粒度分布宽、含有较多粗大桥接颗粒时,经过50 h球磨烧结后,可获得微观组织均匀的合金;球磨时间相同时,3种不同初始WC制备的合金微观组织结构随着烧结温度的升高趋向于更加均匀,合金中的WC晶粒生长更加完整,Co相分布更加均匀。3种WC原料,尽管在粉末形貌、粒度分布等方面存在差异,在球磨50 h、相同温度烧结条件下获得的硬质合金微观组织与力学性能趋于一致,长时间球磨可以弱化初始WC团聚对后续合金结构与性能的影响。WC-4%Co-0.4%Cr_(3)C_(2)alloy was prepared by ball milling at different time and sintering at different temperatures using three kinds of WC raw materials with different particle size distribution characteristics.The changes in microstructure and properties of the alloy were studied.The results show that it is easier to obtain the ultra-fine cemented carbide with uniform WC distribution and grain size when WC powder with concentrated particle size is used.After 50 h of ball milling and sintering of WC raw material with wide particle size distribution and more coarse bridge particles,the alloy with uniform microstructure can be obtained.At the same ball milling time,the microstructure of the alloys prepared with three different initial WC tends to be more uniform with the increase in sintering temperature;the WC grain growth in the alloy is more complete,and the Co phase distribution is more uniform.Although there are differences in powder morphology and particle size distribution of the three kinds of WC raw material,the microstructure and mechanical properties of cemented carbide obtained under the same sintering temperature and ball milling for 50 h tend to be consistent,and long-term ball milling can weaken the influence of initial WC agglomeration on the structure and properties of alloys.

关 键 词：WC 硬质合金 超细 粒度分布 形貌结构 显微组织 性能 

分 类 号：TG135.5[一般工业技术—材料科学与工程]