复相烧结助剂中MnO2对α-Al2O3 陶瓷支撑体性能的影响-中国材料进展

文章信息/Info

Title:: Effect of MnO2 on Properties of α-Alumina Ceramic Supports in Composite Sintering Auxiliaries

Author(s):: LIU Ting; TONG Zhi; WANG Dan; WANG Jiayue; (School of Environmental and Chemical Engineering, Xi’an Polytechnic University, Xi’an 710048, China)

Keywords:: MnO2; α-Al2O3 ceramic supports; porosity; flexural strength; pure water flux; acid/alkali corrosion rate

摘要:: 采用挤压成型法和固态粒子烧结法制备α-Al2O3陶瓷支撑体，主要研究复相烧结助剂MgO-MnO2-TiO2中MnO2添加量(质量分数)对陶瓷支撑体性能的影响。通过压汞法、内外加压法、三点弯曲法、质量损失法、扫描电镜和X射线衍射等方法对α-Al2O3陶瓷支撑体的孔隙率、纯水通量、抗折强度、酸碱腐蚀、微观结构及晶体类型和晶相成分进行分析表征。研究结果表明：MnO2能够和Al2O3形成固溶体Mn2AlO4，使晶格畸化，增加晶体的结构缺陷，从而降低烧结温度，促进α-Al2O3陶瓷支撑体的烧结。当MnO2添加量少于0.5%时，烧结不完全；MnO2添加量大于2%时，晶粒出现异常生长；MnO2的添加量为1.5%时，制备的α-Al2O3陶瓷支撑体样品性能最佳，孔隙率为38.25%，抗折强度为80.3 MPa，纯水通量达6579.52 L/(m2·h·MPa)，酸/碱腐蚀重量损失率为1.22%/0.90%。

Abstract:: The α-Al2O3 ceramic support was prepared by extrusion-forming and solid sintering methods. The effect of MnO2 addition on the performance of ceramic support was mainly studied. Mercury intrusion method, self-made pure water flux measurement device, three-point bending method, mass loss method, SEM and XRD were used to analyze the porosity, pure water flux, flexural strength, acid and alkali corrosion, surface morphology and crystal phases of the α-Al2O3 ceramic support. The results show that: MnO2 can form a solid solution Mn2AlO4 with alumina, which deforms the lattice and increases structural defects, thereby lowering the sintering temperature and promoting the sintering of the α-Al2O3 ceramic support. When the additive amount of MnO2 is less than 0.5%, the sintering is incomplete, and when the additive amount of MnO2 is more than 2%, the crystal grains grow differently. The optimum dosage of MnO2 is 1.5%, where the prepared support has a good performance with a porosity of 38.25%, the flexural strength is 80.3 MPa, the pure water flux is 657952 L/(m2·h·MPa), the weight loss rate of acid/alkali corrosion is only 1.22%/0.90%.