SiC超细粉制备机理研究  

Mechanisms of SiC fine powders preparation

作　　者：申玉芳[1] 邹正光[1] 

机构地区：[1]桂林工学院有色金属材料及其加工新技术省部共建教育部重点实验室,广西桂林541004

出　　处：《材料科学与工艺》2008年第2期278-280,共3页Materials Science and Technology

基　　金：广西自然科学基金资助项目(桂科自0339073);广西新世纪十百千人才工程基金(2002210)

摘　　要：以蒸馏水为研磨介质,采用行星式球磨机对平均粒径约为10μm的SiC粉料进行了球磨,对球磨粉料进行酸洗除铁及水洗,制备出平均粒径为351.5nm的SiC超细粉料,详细分析了粉料制备过程中的物理化学变化与机理.结果发现:粗分散体系长时间球磨所得超细粉体溶液形成胶体分散系,体系固相含量增加,颗粒平均最小间距减小,颗粒间的范氏引力倍增,易形成团聚体;超细粉料胶体溶液在酸洗过程中产生了硬团聚,主要是由于Fe2+氧化水化成为Fe(OH)3胶桥,将超细粉料钳住所致;另外,测试溶液接近SiC等电点时亦会导致颗粒团聚.酸洗去除胶桥、调解溶液pH值可有效消除团聚.SiC powders of 10μm in average diameter were processed with aqueous media via planetary- milling machine and fine powders of 351.5nm in mean size were made. The physical chemistry and mechanisms were studied. It showed that the coarse decentralized system changed into sol architecture came finer, with a decrease in the minimum separation distance between particles and an der Waals force of interaction, causing the particles more easier to agglomeration. Some as the particles beincrease in the van aggregated were caused by the formation of Fe （OH）3 colloidal bridge oxidized and hydrated from Fe^2＋ while and an approaching of the isoelectric point （IEP） of SiC during testing. Agglomeration could be through further pickling and pH value adjustment. particles pickling, separated through further pickling and pH value adjustment.

关 键 词：SiC超细粉 最小间距 Fe(OH)3胶桥 等电点 机理 

分 类 号：TF123.1[冶金工程—粉末冶金]