ZrO2悬浮液性能研究

采用乙醇为溶剂，PVB为分散剂和粘结剂，对固相的质量分数为55％的ZrO2悬浮液的制备和性能进行了研究。通过测定悬浮液的粘度和最终沉降体积，确定最佳分散剂含量。悬浮液的制备分两个阶段：第一阶段，悬浮液由ZrO2粉、乙醇和质量分数为0．7％的PVB(分散剂)组成，球磨24h，目的是打开颗粒团聚体和润湿粉料；第二阶段，主要是使悬浮液与粘结剂的混合，分别加入不同量的PⅦ(粘结剂)，球磨24h。结果表明，分散剂含量为粉体质量的0．7％时，能使ZrO2粉末得到良好的分散；当粘结剂含量少于6％时，在涂层坯体过程中容易出现裂纹；而粘结剂含量高于6％时，悬浮液中含有较多的气泡。加入0．7％分散剂和6％粘结剂，可以获得粘度适中、悬浮稳定的ZrO2悬浮液。

An investigation on the properties of ZrO2 suspensions

The preparation and properties of ZrO 2 suspensions consisting of 55wt% zirconia powder, ethanol, polyvinyl butyral(PVB) as the dispersant and binder were studied The quantitative optimization of dispersant was investigated from the measurement of the viscosity and the final sedimentation volume fraction of suspension with different concentration of PVB as dispersant The suspensions were prepared in two stages First, the dispersant was added to the solvent followed by zirconia powder This slurry was ball milled for 24h in order to separate zirconia particles and to break up weak agglomerates Then binders with different content were added to the above suspension and the resulting slurry was milled for 24h The results show that the zirconia powder in suspension with 0 7wt% PVB as dispersant can be dispersed well For binder content lower than 6wt%, cracks are noticed during drying when the green coatings are handled For binder content more than 6wt%, there are many air bubbles in suspension The zirconia suspension with suitable viscosity, and stability is obtained in ethanol with 0 7wt% PVB as dispersant and 6wt% PVB as binder