多孔氮化硅陶瓷的研究进展及构效关系中的矛盾平衡  

Research Progress and Contradictory Equilibrium of Structure-PerformanceRelationship of Porous Silicon Nitride Ceramics

作　　者：马茸茸 张电[1,2] 刘一军 刘静 杨晓凤 李延军[1] 马爱琼 MA Rongrong;ZHANG Dian;LIU Yijun;LIU Jing;YANG Xiaofeng;LI Yanjun;MA Aiqiong(College of Materials Science and Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,China;State Key Laboratory of Advance Refractories,Sinosteel Luoyang Institute of Refractories Research Co.,Ltd.,Luoyang 471039,China;Monalisa Group Co.Ltd,Foshan 528211,China)

机构地区：[1]西安建筑科技大学,材料科学与工程学院,西安710055 [2]中钢集团洛阳耐火材料研究院有限公司,先进耐火材料国家重点实验室,洛阳471039 [3]蒙娜丽莎集团股份有限公司,佛山528211

出　　处：《材料导报》2020年第9期101-109,共9页Materials Reports

基　　金：陕西省重点研发计划(2018GY-113);先进耐火材料国家重点实验室开放课题(201804);西安建筑科技大学材料科学与工程学院青年博士基金项目。

摘　　要：多孔氮化硅陶瓷(Si 3N 4-PC)在流体过滤器、催化剂载体、宽频透波材料、复合材料乃至组织工程等领域存在广阔的应用前景。近年来,Si 3N 4-PC的研究主要致力于发展多种方法以提高气孔率并优化孔形貌,从而改善渗透率和比表面积等重要参数。通常,不完全烧结法制得的Si 3N 4-PC气孔率仅40%,而模板复制法和直接发泡法制得的Si 3N 4-PC气孔率高达70%以上,但其力学性能明显恶化,耐压强度仅为10 MPa。通过调控烧结工艺、原料和烧结剂,生成大量纤维状和柱状的微观组织,可使Si 3N 4-PC弯曲强度提高至100 MPa以上,然而,气孔率却降至55%以下。此外,一些研究将挤出成形法、牺牲模板法与不同烧结工艺相结合,试图形成耦合孔结构以兼顾气孔率和力学性能,但效果不佳。当前研究中,Si 3N 4-PC的制备方法、孔结构和性能数据及其规律性缺乏梳理和总结,提高Si 3N 4-PC的综合性能遭遇瓶颈。实质上,气孔率和孔形貌是渗透率等参数的主要影响因素,而孔壁则是承受载荷的中心,孔壁的显微结构是Si 3N 4-PC力学性能的决定因素,并对比表面积等核心指标产生显著影响,而原料种类和高温过程是孔壁结构形成的基础和控制机制。针对这些基本问题,本文分析了近年来Si 3N 4-PC的制备及应用等研究工作,将目前Si 3N 4-PC的制备方法归纳为两类,即通过烧结形成气孔法与通过成形引入气孔法。前者包括不完全烧结法、相变烧结法、反应烧结法和碳热还原氮化法,后者包括挤出成形法、直接发泡法、模板复制法和牺牲模板法等;分析了这些方法制备Si 3N 4-PC的特点和不足;通过文献数据汇总标明了当前Si 3N 4-PC的气孔率和强度等性能水平;揭示气孔率-强度及孔径-比表面积等构效关系中的矛盾平衡是制约其综合性能的瓶颈。基于颗粒原料及工艺,Si 3N 4-PC的综合性能难以突破,若采用Si 3N 4晶须和纤维�Porous Si 3N 4 ceramics(Si 3N 4-PC)have a promising application prospect in the broadband wave-transparent materials,fluid filter,catalyst carrier,composite and even tissue engineering.In recent years,researches are dedicated to develop preparing methods of Si 3N 4-PC in order to promote the porosity and optimize the pore morphology,thereby improve the application properties such as permeability and specific surface area.Generally,the porosity of Si 3N 4-PC prepared by partial sintering is only 40%while that by template replication and direct foaming are higher than 70%.However,the latter two methods produce poor mechanical properties to low compressive strength level of 10 MPa.Controlling the sintering process,raw materials and sintering additives can produce massive fibers and columnar microstructures,which enhance the Si 3N 4-PC to gain high bending strength of 100 MPa.However,this leads to negative effect on porosity which is as low as 55%.In addition,some researches give consideration to both porosity and mechanical properties via coupling pore structure prepared by combining the extrusion and sacrificial template with varied sintering process.Nevertheless,the effect is not satisfactory.The preparing methods,pore structures and properties data in current researches of Si 3N 4-PC as well as the relationship among them need to be classified and summarized.The improvement of comprehensive performance of current Si 3N 4-PC encounter bottleneck.In essence,the poro-sity and pore morphology determine application properties such as the permeability of Si 3N 4-PC.The pore wall is the load-bearer and its microstructure is the deci-sive factor of mechanical properties and also of great significance on core indicators such as specific surface area.The species of raw materials and sintering process are substance and control mechanism of pore wall microstructures.This review analyzes current researches about the preparations and applications of Si 3N 4-PC and classifies its preparations methods as two categories,i.e.produ

关 键 词：多孔氮化硅陶瓷 构效关系 矛盾平衡 气孔率-强度 孔径-比表面积 

分 类 号：TQ174[化学工程—陶瓷工业]