多孔基体孔结构对梯度膜层成膜及性能的影响  

Pore Structure of Porous Matrix on Formation and Properties of Gradient Membrane

作　　者：刘渊 刘忠军 姬帅[1] 荆远 刘卓萌 Liu Yuan;Liu Zhongjun;Ji Shuai;Jing Yuan;Liu Zhuomeng(School of Materials Science and Enginneering,Xi'an Shiyou University,Xi'an 710065,China)

机构地区：[1]西安石油大学材料科学与工程学院,陕西西安710065

出　　处：《稀有金属》2021年第4期420-427,共8页Chinese Journal of Rare Metals

基　　金：国家自然科学基金项目(51704239);西安石油大学校青年创新团队项目(2019QNKYCXTD12),西安石油大学青年科技创新基金项目(2016BS21)资助;陕西省高等教育学会2017年度高等教育科学研究项目(XGH17091);陕西省科研创新训练项目(S201910705050)。

摘　　要：梯度多孔材料是指在孔径尺寸或孔隙率等方面具有梯度变化特征的一类多孔材料,在其制备生产过程中,多孔基体的孔径尺寸及孔形貌与覆膜粒子粒径的匹配度会严重影响该材料的孔结构及性能。本文通过观察多孔基体的孔形貌变化,旨在研究其对梯度膜层材料性能的影响规律。本实验采用不同粒径范围的316L不锈钢粉末为原料,通过模压法制备不锈钢多孔基体;配制TiO_(2)悬浮液,通过挂浆法制备前驱体,同时采用Ar保护烧结来制备不同基体孔径的复合梯度多孔材料。本研究对样品的孔结构、组织成分及微观形貌进行表征分析;通过对其透气性能进行研究发现,当膜层烧结温度为650℃、316L多孔不锈钢基体的孔径为15.7μm、TiO_(2)粉末粒径为2.5μm时(中位径D_(50)),所制备的梯度多孔材料透气性能最优,说明当多孔基体孔径与覆膜粒子粒径的差值越小时,该梯度多孔材料的性能越优;同时发现,烧结过程中由于TiO_(2)膜层与基体烧结膨胀收缩差异的存在,导致基体与梯度膜层间易产生烧结开裂,从而影响多孔材料的性能。Gradient porous material was one kind of porous materials with pore size or porosity gradient along filter thickness directions.During fabrication,the matching between the pore size and pore morphology of the porous substrate and the membrane particle size seriously affected the material properties.The purpose of this research was to study the morphology of porous substrates in order to indicated its influence on the properties of gradient membranes.This work mentions the different size range(150~250,58~96 and<38μm)of 316 L stainless steel powder particles as the raw materials which were at different sintering temperatures of 1170,1200 and1230℃,TiO_(2) powder with an average particle size of 2.5μm was added into alcohol and fully stirred to obtain a stable suspension with a solid content of 5%,the stainless steel matrix was repeatedly immersed in the suspension,and then put into the drying oven for drying,to obtained a uniform thickness film,at the same time used Ar protection at different sintering temperatures(650,720 and800℃)to the preparation of metal-ceramic composite gradient according to different matrix apertures of porous materials.The pore structure and phase composition were characterized and analyzed,respectively.According to XRD result,when the sintering temperature was 650℃,the TiO_(2) film was dominated by Anatase structure,and contained a small amount of Rutile structure.When the sintering temperature rised to 720℃,the Anatase type characteristic peak and Rutile type characteristic peak of TiO_(2) film did not change.When the sintering temperature rised to 800℃,most of the Anatase type characteristic peaks of TiO_(2) film disappeared,and a large number of Rutile type characteristic peaks appeared.The experimental results showed that the TiO_(2) crystal transition zone existed between 720 and 800℃.When the sintering temperature was higher than 800℃,most of the Anatase crystal structure is transformed into Rutile crystal structure.SEM images showed that the surface of the matrix mate

关 键 词：梯度多孔材料 挂浆法 孔形貌 透气性 匹配度 

分 类 号：TK91[动力工程及工程热物理]