中文摘要：

用不同细度的铁矿粉、细度为76μm（200目）硅粉和G级油井水泥，制备了不同密度的水泥浆并测定其流变性能。用扫描电子显微镜观察了硬化水泥浆体的微观形貌，并讨论了铁矿粉在水泥浆中的分布状态对于水泥浆流变性能的影响，结果表明：在硬化高密度水泥浆中，惰性的铁矿粉和硅粉分散在水化产物连续基体中;其浆体的致密程度由水泥的水化产物控制；最紧密堆积理论不能指导高密度水泥浆的配方设计。优先采用细铁矿粉配制水泥浆，易于获得流变性能合格的高密度水泥浆。

英文摘要：

Cementing slurries of different densities were prepared with hematite of different finenesses, 76μm silica fumes and grade G oil well cement. The rheological properties of fresh slurries were tested. The micromorphology of hardened slurries was observed by scanning electron microscope. The results show that in hardened cement paste, inert hematite and silica fume were scattered in the continuous matrix of hydration products of cement. The compacting degree of hardened slurry was controlled by the hydration products. The close accumulation theory can＇t be the design reference of high density slurry. The results show that fine hematite makes better high density cementing slurry of qualified rheological properties.