摘要
探讨了采用机械合金化结合高温烧结法,以氧化锆为锆源、炭黑为碳源、镁粉为还原剂制备ZrC超微粉的可行性,采用XRD、SEM对ZrC的成分和形貌进行了观察和分析,并对采用氧化物制备难熔相进行了热力学分析对比。球磨过程中原料粉末不断细化,有助于氧化物与还原剂的紧密结合;随后的烧结过程中,可降低ZrC的生成温度,与其伴生的MgO有助于抑制ZrC颗粒的生长。以ZrO_2为锆源,利用机械合金化和高温烧结可得到纯度较高且粒度为纳米级的ZrC粉末。
Taking ZrO2 as zirconium source, carbon black as carbon source, and Mg powder as reductant, the ZrC micro powders are prepared by mechanical alloying and high temperature sintering. Using XRD and SEM, ZrC powders are also observed and analyzed. The thermodynamic analysis is also concerned with the production of different refractory phases using the corresponding oxides. In the milling process, raw powder decrease continuously,and the refined oxides tend to be combined closed with the reductant. These can decrease the producing temperature of ZrC in the sintering process followed. The by product of MgO co-exists with the powder of ZrC, and may hinder the growth rate of ZrC in the sintering process. It may be possible to produce higher purity and nano particle size ZrC by mechanical alloying and high temperature sintering when taking ZrO2 as zirconium source.
关键词
ZRC
纳米
球磨
烧结
ZrC,nanocrystalline, milling, sintering