有机泡沫浸渍法制备多孔氧化铝陶瓷工艺研究

摘要

有机泡沫浸渍法是当前制备多孔陶瓷最为常见的一种工艺，因其可以制备出气孔分布均匀、气孔率超高、贯通且结构为三维立体网络状的多孔陶瓷。

本文研究了添加不同种类以及不同含量的分散剂对α-Al2O3在悬浮液中稳定性的影响，结果表明当固含量为5wt%时，选用阿拉伯树胶分散剂、且添加量为0.8wt%时，静置12小时后，α-Al2O3悬浮液的稳定性最佳。为了有效降低氧化铝陶瓷的烧结温度，通过实验研究选择的助烧剂质量比为2:1的SiO2/CuO，添加量为3wt%。使用气孔率分别为75%、80%、95%的有机泡沫模板，在固含量选取为30wt%的悬浮液中浸渍后干燥，最后在1200℃烧结2h，分别制备得到了气孔率为65%、72%、93%的多孔氧化铝陶瓷。可见有机泡沫浸渍法是一种气孔率可大范围调控的多孔陶瓷制备工艺。

关键词：悬浮液稳定性；有机泡沫浸渍法；多孔氧化铝陶瓷；助烧剂

Abstract

The polymeric sponge impregnation process is the most common process of the preparation of porous ceramics,since this method can prepare porous ceramics with uniform pore distribution, through holes,three-dimensional network structure and high porosity porous ceramic.

This paper studies the effect of different types and different dosage of dispersants on the stability of α-Al2O3powders in the suspension. The results show when the solid content was 5wt%, gum arabic was chosen as the dispersant and its dosage was 0.8wt%, α-Al2O3 powders in the suspension had the best stability after laying aside for 12 hours. In order to lower the sintering temperature of the alumina ceramic, sintering aids of SiO2/CuO with a weight ratio of 2:1 and dosage of 3wt%, were added in the starting materials. When the PU foams with porosity of 75%, 80%, 95% respectively were used as the templates, and the solid content of the suspension was 30wt%, porous alumina ceramic with porosity of 65%, 72%, 93% respectively were prepared. In a word, the organic foam impregnation method is a ceramic preparation process which can achieve the control of porosity in a large range.

Key words：stability of the suspension; polymeric sponge impregnation process; porous alumina ceramics; sintering aids

目录

前言 (1)

1绪论 (2)

1.1氧化铝多孔陶瓷的性能特点及发展应用 (2)

1.2多孔陶瓷的制备方法 (2)

1.2.1有机泡沫浸渍法 (2)

1.2.2发泡法 (3)

1.2.3 造孔剂法 (4)

1.2.4木材陶瓷化工艺 (5)

1.2.5直接烧结法 (6)

1.3有机泡沫浸渍法制备氧化铝陶瓷工艺要点 (6)

1.3.1有机泡沫的选择和预处理 (6)

1.3.2悬浮液的制备 (7)

1.3.3悬浮液稳定性的表征 (13)

1.3.4 挂浆工艺 (14)

1.4氧化铝陶瓷的低温烧结技术 (14)

1.4.1降低陶瓷烧结温度的方法 (15)

1.4.2常用的低温烧结复合助剂 (15)

1.4.3烧结助剂降低氧化铝陶瓷烧结温度机理 (16)

1.4.4 低温烧结复合助剂的选配原则 (18)

1.5 有机泡沫浸渍法制备多孔陶瓷的研究现状 (18)

1.6 本文的研究内容和意义 (19)

2.1 实验原料及设备 (20)

2.1.1 实验原料 (20)

2.1.2 实验设备 (20)

2.2 悬浮液的制备 (21)

2.2.1 分散剂的选择 (21)

2.2.2 pH调节 (22)

2.3 沉降法测试悬浮液稳定性 (22)

2.4 测试结果分析 (22)

2.5 坯体的制备 (25)

2.5.1 有机泡沫模板制作与预处理 (25)

2.5.2 挂浆与干燥 (25)

3 氧化铝陶瓷低温烧结工艺研究 (26)

3.1 实验材料 (26)

3.2 实验设备 (26)

3.3 不同助烧体系对氧化铝陶瓷烧结的影响 (26)

3.4 XRD和扫描电镜检测 (27)

4 多孔氧化铝陶瓷低温烧结 (32)

4.1 气孔率测定 (32)

4.2助烧剂对多孔氧化铝陶瓷的性能影响及分析 (33)

5 结论 (32)

致谢 (33)