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以蓝晶石和Al_2O3粉体为原料、PMMA微球为造孔剂、Isobam104为分散胶凝剂，结合凝胶注模工艺与造孔剂法，实现了收缩率可控的多孔莫来石陶瓷的近净尺寸制备。研究了烧结温度对相组成的影响以及固相含量对样品微观结构、相组成、收缩率、气孔率及抗压强度的影响。结果表明：随着固相含量的增加，样品在1 500℃烧结后收缩率先减小后增大，在固相含量为30%(体积分数)、造孔剂含量为30%(质量分数)时，样品的总收缩率接近于0，实现了多孔莫来石陶瓷的近净尺寸制备。多孔莫来石陶瓷呈现出较高的气孔率(60.4%)、较小的平均气孔尺寸(3.75μm)和较高的抗压强度(8.3 MPa)。利用制备过程中的体积膨胀效应，可以有效地控制多孔陶瓷制备过程中的收缩率，实现了多孔莫来石陶瓷的近净尺寸制备，对制备大尺寸复杂形状多孔陶瓷部件、降低加工成本具有重要参考价值。
Abstract：Near net size preparation of porous mullite ceramics with controllable shrinkage was achieved via gel casting and pore-forming agent process With Al_2O3 and kyanite as raw materials, PMMA microspheres as a pore-forming agent, and isobutylene/maleic anhydride copolymer(Isobam104) as a gelling/dispersing agent. The effect of sintering temperature on the phase composition and the effect of solid loading on the microstructure, phase composition, shrinkage, porosity, and compressive strength of samples were investigated. The results show that the shrinkage of samples sintered at 1 500 ℃ firstly decreases and then increases as the solid loading increases. At the solid loading of 30%(in volume fraction) and the content of pore forming agent of 30%(in mass fraction), the total shrinkage of the samples is close to zero, realizing the near net size preparation of porous mullite ceramics. The prepared porous mullite ceramics exhibite a higher porosity(i.e., 60.4%), a smaller average pore size(i.e., 3.75 μm) and a higher compressive strength(i.e., 8.3 MPa). The shrinkage of porous ceramics can be effectively controlled by the volume expansion effect in the preparation process, and the near net size preparation of porous mullite ceramics is of great significance for the preparation of large-size and complex porous ceramic parts and the reduction of processing cost.
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基本信息:
DOI：10.14062/j.issn.0454-5648.20210751
中图分类号:TQ174.1
引用信息:
[1]颜浩,陈仕乐,郎莹,等.多孔莫来石陶瓷的近净尺寸制备及性能[J].硅酸盐学报,2022,50(03):698-703.DOI:10.14062/j.issn.0454-5648.20210751.
基金信息:
国家自然科学基金(51872159)
2021-08-31
2021
2022-01-05
2022
2022-01-06
1
2022-01-24
2022-01-24
2022-01-24