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化学共沉淀法是制备纳米粉末的有效途径之一 ,但粉末在煅烧过程中产生的团聚现象严重地影响了粉末的各项性能。本文通过在传统的化学共沉淀法中加入一种较新的脱水工艺——蒸馏法制备了纳米级的 Zr O2 复合粉末。结果表明 :蒸馏法能充分地脱去凝胶中残余的水分 ,防止因胶体含水而引起的粉末硬团聚 ,从而显著地提高了粉末的性能。制得的氧化锆复合粉末一次粒径已达到纳米级 ,粉末分散性良好 ,团聚体尺寸小而少 ,并具有较好的烧结性能。经过常压成型后于 1 40 0℃烧结 2小时 ,制备了致密 ( 98.3% )且具有良好晶粒度的氧化锆复合陶瓷。
Chemical coprecipitation is one of the effective ways to prepare nano-powders. However, agglomeration of powders during calcination seriously affects the properties of the powders. In this paper, nano-scale ZrO2 composite powders were prepared by adding a new dehydration technology-distillation method to the traditional chemical coprecipitation method. The results show that the distillation method can fully remove the residual moisture in the gel and prevent hard agglomeration of the powder caused by the hydration of the colloid, so as to remarkably improve the performance of the powder. The prepared zirconia composite powder has the primary particle size of nanometer, good powder dispersibility, small and small aggregate size, and good sintering performance. After atmospheric pressure forming and sintering at 140 ℃ for 2 hours, dense (98.3%) zirconia composite ceramics with good grain size were prepared.