室温电流快速烧结氧化镁陶瓷工艺及机理  

Process of and Mechanism for Rapid Current Sintering of MgO Ceramics at Room Temperature

作　　者：张明涛 许岗[1] 李焕勇[2] 张斌斌 尹煜 ZHANG Mingtao;XU Gang;LI Huanyong;ZHANG Binbin;YIN Yu(School of Materials Science and Chemical Engineering,Xi’an Technological University,Xi’an 710021,China;School of Materials Science,Northwestern Polytechnical University,Xi’an 710072,China)

机构地区：[1]西安工业大学材料与化工学院,西安710021 [2]西北工业大学材料学院,西安710072

出　　处：《西安工业大学学报》2023年第1期41-47,共7页Journal of Xi’an Technological University

基　　金：陕西省自然科学基础研究计划项目(2021JM 057)。

摘　　要：为了减少陶瓷烧结的能耗,降低烧结温度,探究常温下快速高效烧结陶瓷的制备方法。文中采用氧化镁为模型材料,使用LiCl溶液的辅助下通过将电流施加在生坯上进行室温下的陶瓷烧结,获得了一定致密度的MgO陶瓷。研究结果表明:阈值电场强度随着LiCl(烧结助剂)含量的增加而降低;升压速率与阈值电场强度呈反比关系。MgO陶瓷烧结的最佳工艺:LiCl的摩尔占比为10%,升压速率为50 V·s^(-1),烧结时间为60 s。通过模拟生坯快速升温时电导率的变化特征,提出了室温电流烧结陶瓷的机理:LiCl溶液中的Li^(+)和Cl^(-)为烧结初期提供电导载体;随温度升高,生坯中水分和部分LiCl挥发,部分LiCl熔化后继续使生坯保持导电,从而维持了陶瓷的电流烧结。The paper examines the feasibility of the current sintering of MgO ceramics at room temperature to reduce the energy consumption and sintering temperature.Gradually increasing electric field intensity was applied to the green body at room temperature until current sintering occurred.The results show that the threshold electric field decreases with the increase in LiCl content.The rate at which the voltage increases is inversely proportional to the threshold electric field strength.The optimum conditions for the sintering of MgO ceramics were 10 mol%LiCl,50 V·s^(-1) of increasing rate of voltage,and 60 s of sintering times.The mechanism for current sintering of ceramics at room temperature was proposed by simulating the characteristics of the conductivity change when the green body was rapidly heated.LiCl is a key to the effective increase in the conductivity of the specimen,in the form of Li+and Cl^(-)ion.As the temperature increases,the water of LiCl solution in the green body gradually evaporates.After part of LiCl is molten,Li+and Cl^(-)ion provide the continuous carrier on the conductivity of the sample,thus maintaining the current sintering needed for the ceramic.

关 键 词：室温烧结 电流烧结 MgO陶瓷 烧结机理 

分 类 号：TQ174.758.11[化学工程—陶瓷工业]