水基流延工艺制备氧化铝生带材料研究

Study on the Preparation of Al_2O_3 Green Tapes by Aqueous Tape Casting

利用水基流延法,选用纯丙乳液作为粘结剂,成功制备出表面光滑、结构均匀、柔韧性良好、强度较高的Al2O3生带材料,并发现当分散剂聚丙烯酸铵(PAA-NH4)含量为2.5%(质量分数)、粘结剂纯丙乳液用量为27%～28%(体积分数)、pH值为9.5～10时可制备出稳定性良好、流动性适宜的α-Al2O3的水基流延浆料。对纯丙乳液进行了DTA和TGA热分析,在此基础上确定流延素片的排胶温度在500oC;将该工艺制备的α-Al2O3流延素片在1650oC并保温2h的烧结条件下,获得了强度和致密度都较高的烧结体,其中烧结较好的流延片的相对密度达到94.5%。

The alumina green tapes were fabricated successfully, which had smooth surface, homogeneous microstructure, good flexibility and high strength through aqueous tape casting with pure acrylic emulsion as binders. It is concluded that the appropriate alumina suspensions for tape-casting with low viscosity and good stability can be prepared, in the condition that the contents of dispersants and binders were 2.5wt% and 27vol%-28vol%, respectively, and the pH value was 9.5-10. The alumina green tapes produced by the aqueous tape casting process can possess high strength and density after sintered at 1650℃ with a holding time of 2 h. The relative density of 94.5% can be obtained for the well-sintered sample. This paper has also studied the film of pure acrylic emulsion by means of DTA and TGA, and according to the results, a suitable binder-removal system has been set up for the sintering of the alumina green tapes.