【摘要】 采用高能球磨法制备了纳米晶掺Y硬质合金粉末。用XRD,SEM和DTA等分析检测手段,研究了纳米晶掺Y硬质合金粉末的结构、形貌和相的变化。结果表明:高能球磨45h,可获得晶粒尺寸约为8nm的掺Y硬质合金粉末;微量Y的加入,有利于硬质合金粉末晶粒的细化;在25～45h范围内,随着高能球磨时间的延长,粉末晶粒尺寸减小,且掺Y硬质合金粉末的晶粒尺寸比未掺Y的硬质合金粉末晶粒尺寸要细一倍;高能球磨25h,粉末中Co相的X射线衍射峰消失。高能球磨掺Y硬质合金粉末的DTA曲线在626℃出现了1个尖锐的放热峰。高能球磨掺Y硬质合金粉末固结之后,其合金晶粒细小,机械性能较好。更多还原

【Abstract】 The nano-crystalline Y-doped WC/Co powder was prepared by high energy ball milling. The nano-crystalline powders were characterized by means of XRD, SEM and DTA. The results show that nano-crystalline powder with grain size of 8 nm is obtained after ball milling for 45 h, and adding trace rare earth elements into carbides is effective to minify the grain size of WC/Co powder. The grain size of Y-doped powder becomes two times smaller as compar with the undoped powder within ball milling times of 25～45 h. The XRD peak of Co phase disappears after 25 h ball milling. A sharp peak of heat release at the temperature of 626 ℃ is emerged in DTA curve within the range of heating temperature. After consolidate the Y-doped WC/Co alloy by high energy ball milling exhibite ultra-fine grain sizes and better mechanical properties.更多还原