微量钴对无金属粘结相WC硬质合金烧结致密化与WC晶粒生长行为的影响  

Effects of Small Amount of Cobalt Addition on Densification and WC Grain Growth during Sintering of Binderless Cemented Tungsten Carbide

作　　者：张立[1,2] 陈述[3] 黄方杰[1] 单成[1] 程鑫[1] 马鋆[1] 

机构地区：[1]中南大学粉末冶金国家重点实验室,湖南长沙410083 [2]硬质合金国家重点实验室,湖南株洲412000 [3]长沙矿冶研究院有限责任公司分析检测中心,湖南长沙410012

出　　处：《硬质合金》2011年第5期271-275,共5页Cemented Carbides

基　　金：国家自然科学基金资助项目(51074189;50823006);湖南省科技计划重点项目(2010FJ2006);高等学校博士学科点专项科研基金项目(20100162110001);国家科技重大专项(2009ZX04012-032;2011BAE09B02)

摘　　要：采用Cr3C2、VC掺杂超细WC为原料和无压真空烧结工艺,通过合金微观组织结构的观察与分析,研究了添加质量分数为0.3%的Co对无金属粘结相WC硬质合金烧结致密化与WC晶粒生长行为的影响。结果表明,微量Co的存在加速了WC的烧结致密化过程,与此同时也导致了WC晶粒明显的各向异性非连续晶粒长大。在上述研究基础上,提出了一种无金属粘结相WC硬质合金的低成本制备工艺,探讨了超细硬质合金中WC晶粒生长机制,提出了超细硬质合金的质量改进建议。Using the ultrafine WC powder doped with Cr3C2 and VC as the raw material,the effects of 0.3% cobalt（mass fraction） addition on the densification and WC grain growth during the sintering process of the binderless cemented tungsten carbide,which was sintered in a conventional vacuum furnace,were investigated through the microstructure observation.It is shown that the densification of tungsten carbide is accelerated due to the existence of small amount of cobalt,accompanied by an anisotropic and discontinuous WC grain growth.Based on the research,a preparation technique of binderless cemented tungsten carbide with low cost is suggested.The mechanism of the WC grain growth is discussed and the quality improvement is proposed for the ultrafine cemented carbide.

关 键 词：无金属粘结相硬质合金 烧结 晶粒生长机制 晶粒生长抑制 超细硬质合金 

分 类 号：TG135.5[一般工业技术—材料科学与工程]