CSLST微波介质陶瓷的流延浆料的制备工艺研究

Study on Preparation Technology of Tape-casting Slurry on CSLST Microwave Dielectric Ceramic

以二甲苯,正丁醇混合溶液作为分散溶剂,自制的BM-2为粘结剂,聚乙二醇PEG为增塑剂对添加烧结助剂B2O3-CuO-Li CO3（BCL）的（Ca0.9375Sr0.0625）0.2（Li0.5Sm0.5）0.8TiO3（CSLST）微波介质陶瓷粉体进行流延浆料制备工艺研究。通过研究各种添加剂含量对含55%陶瓷基料粉体的浆料流变性能的影响,得出了合适的浆料添加剂配比为：混合溶液二甲苯与正丁醇的比例为1∶1（体积比）,粘结剂BM-2为8wt%~11wt%,增塑剂PEG为2wt%~3wt%。该浆料具有典型剪切变稀行为的塑性流体特性,经流延可制备均匀无裂纹的流延膜片。膜片叠层后在875℃下烧结具有较佳的微波介电性能：介电常数εr=51.8,品质因数Q×f=1085 GHz,谐振频率温度系数τf=19.38×10-6/℃。

The tape-casting slurry of（ Ca0. 9375Sr0. 0625）0. 2（ Li0. 5Sm0. 5）0. 8TiO3（ CSLST） microwave dielectric ceramic powder with B2O3-CuO-Li CO3（ BCL） sintering aid was researched using BM-2 as binder,polyethylene glycol as plasticizer, and dimethylbenzene mixed butyl alcohol as dispersion medium. Suitable slurry mass fraction components of tape-casting slurry are： the solid content of ceramic powder is 55%,the ratio of dimethylbenzene to butyl alcohol is 1∶ 1（ volume）,binder is 8wt%-11wt%,and plasticizer is 2wt%-3wt%. The slurry has the shear-thinning characteristics. A well uniform green tape without crazing can be obtained by tape-casting. The diaphragm laminated later sintering at 875 ℃has preferable microwave dielectric properties： dielectric constant εr= 51. 8,quality factor Q × f = 1085 GHz,resonance frequency temperature coefficient τf= 19. 38 × 10- 6/ ℃.