摘要
以硅溶胶为前驱体,经酸碱催化与莫来石纤维毡浸渍复合,通过凝胶老化、超临界干燥等工艺制备莫来石纤维增强硅基气凝胶隔热材料,采用SEM、XRD、红外光谱和数字图像相关技术等方法,研究高温处理硅基气凝胶材料力学性能规律与动态响应,并表征高温下微观结构变化等。结果表明,硅基气凝胶隔热材料表现出轻质(0.39 g/cm^(3))、较低热导率1000℃时0.068 W/(m·K)及良好的高温力学性能,其压缩强度及模量随着热处理温度升高而增大,在1000℃测试时形变10%的压缩强度约0.4253 MPa,比室温时提高了43.3%,压缩应变-位移场分布情况说明了压缩力在材料内部传递过程中逐渐递减。室温时拉伸强度约为1.39 MPa,在1000℃拉伸试验时其拉伸强度比室温时提高了102.2%,高温处理有助于拉伸应变场分布更为均匀。
Mullite fiber reinforced silica aerogel thermal insulation material was prepared by using silica sol as precursor,adding acid-base catalyst,impregnating and compounding with mullite fiber felt,and then gel aging and supercritical drying.The effects of high temperature treatment on the microstructure,structure and static/dynamic mechanical properties of reinforced silica aerogel thermal insulation materials were studied by SEM,XRD,infrared spectroscopy and digital image correlation method.The results show that the density of the material was about 0.39 g/cm^(3),and the thermal conductivity at 1000℃was about 0.068 W/(m·K).The compressive strength and compressive modulus increase with the increase of temperature.At 1000℃,the compressive strength of 10%deformation was about 0.4253 MPa,which was 43.3%higher than that at room temperature before high temperature treatment.The compressive strain-displacement field show that the compressive force decreases gradually in the process of material internal transmission.The tensile strength at room temperature is about 1.39 MPa,and the tensile strength at 1000℃was 102.2%higher than that before high temperature treatment.High temperature treatment helps to make the distribution of tensile strain field more uniform.
作者
周玉贵
陈之伟
苏冬
季惠明
ZHOU Yugui;CHEN Zhiwei;SU Dong;JI Huiming(Key Laboratory of Advanced Ceramics and Machining Technology,Ministry of Education,School of Materials Science and Engineering,Tianjin University,Tianjin 300350,China;Aerospace Institute of Advanced Materialsand Processing Technology,Beijing 100074,China)
出处
《功能材料》
北大核心
2025年第6期6001-6006,共6页
Journal of Functional Materials
基金
国家自然科学基金项目(51972222)。
关键词
高温处理
气凝胶
复合材料
力学性能
数字图像相关技术
high temperature treatment
aerogel
composite
mechanical properties
digital image correlation method
