非水基流延法制备Y_3Fe_(4.85)O_(12)铁氧体基片

Preparation of Y_3Fe_(4.85)O_(12) Ferrite Substrates by Non Aqueous Tape Casting

采用非水基流延成型工艺制备Y3Fe4.85O12铁氧体基片,分析了分散剂种类及用量、固相含量等因素对浆料流变性能的影响,并研究制定流延膜片的排胶制度及烧结工艺。研究结果表明:分散剂OP-85的分散效果明显优于磷酸三乙酯,其最佳的分散剂添加量为0.65wt%。固相含量为25vol%和30vol%的浆料具有典型剪切变稀行为的Herschel/Bulkley流体特征,适合于流延成型。TG-DSC数据分析说明:在温度为400℃的条件下,流延膜片内的有机成分已经完全分解。当烧结温度为1490℃时,烧结膜片的体积密度达到5.09 g/cm3,接近于98%的理论密度。X射线衍射分析烧结膜片晶相纯正,扫描电镜照片显示烧结膜片的微观结构均匀。

Y3Fe4.85O12 ferrite substrates were fabricated through non aqueous tape casting process.The effects of dispersant and solid loading on the rheological property of suspensions were characterized.The decomposition and sintering process for the tapes were discussed,respectively.The test results showed that compared with Triethyl phosphate,good dispersion for the dispersant OP-85 was found in the slurry,and the optimum addition reached to 0.65 wt%.The suspensions including 25 vol%and 30 vol% solid loading belonged to the classical Herschel/Bulkley model,namely exhibited obvious shear thinning behavior,which was suitable for the tape casting.The DSC and TG analysis showed that the organic additives in the tapes decomposed completely at 400 ℃.The bulk density of the tapes sintered at 1490 ℃ reached 5.09 g/cm3,nearly up to about 98% of the theoretical density.In addition,the second phase was not observed from the XRD patterns of Y3Fe4.85O12 sintered tapes and the SEM images showed the sintered samples had a homogeneous microstructure.