Yb_(2)Si_(2)O_(7)基复合材料的高温自愈合行为研究  

Research on the High Temperature Self-Healing Behavior of Yb_(2)Si_(2)O_(7)-Based Matrix Composites

作　　者：刘玥豆 王旭 刘玲[1,2] 马壮[1,2] 杨茗佳[3] LIU Yuedou;WANG Xu;LIU Ling;MA Zhuang;YANG Mingjia(School of Materials Science and Engineering,Beijing Institute of Technology,Beijing 100081,China;National Key Laboratory of Science and Technology on Materials Under Shock and Impact,Beijing Institute of Technology,Beijing 100081,China;Beijing Xinghang Electro-Mechanical Equipment Co.,Ltd.,Beijing 100074,China)

机构地区：[1]北京理工大学材料学院,北京100081 [2]北京理工大学冲击环境材料技术国家级重点实验室,北京100081 [3]北京星航机电装备有限公司,北京100074

出　　处：《中国材料进展》2025年第3期217-225,共9页Materials China

摘　　要：SiC_(f)/SiC陶瓷基复合材料满足新一代航空发动机高推重比的发展要求,但在发动机内部高温恶劣环境下,需用环境障涂层对该复合材料进行防护。目前环境障涂层在服役过程中不可避免地会产生裂纹,因此,需要开发一种具有自愈合能力的环境障涂层,在裂纹出现时及时修复。以Yb_(2)Si_(2)O_(7)材料为基础,分别采用放电等离子烧结和无压烧结制备了Yb_(2)Si_(2)O_(7)-SiC和Yb_(2)Si_(2)O_(7)-Yb_(2)SiO_(5)复合陶瓷,开展了Yb_(2)Si_(2)O_(7)基复合材料的自愈合行为研究,并探究了该复合材料作为自愈合环境障涂层材料的可行性。结果表明,向Yb_(2)Si_(2)O_(7)陶瓷中添加SiC第二相时,含5%和10%(质量分数,下同)SiC的Yb_(2)Si_(2)O_(7)-SiC复合材料在空气中1100℃热处理1 h后,由于表面的SiC氧化形成SiO_(2),SiO_(2)的填充作用以及反应引起的体积膨胀促进了裂纹愈合;而在1300℃下热处理,SiC大量氧化产生较大体积膨胀,含5%和10%SiC的Yb_(2)Si_(2)O_(7)-SiC复合材料内部反而出现新的裂纹。而向Yb_(2)Si_(2)O_(7)陶瓷中添加Yb_(2)SiO_(5)第二相可以促进材料致密化和裂纹愈合,当Yb_(2)SiO_(5)添加量为50%时,复合材料的裂纹愈合效率最高,约为78%,主要可归因于具有较高热膨胀系数的Yb 2SiO 5受热膨胀,对Yb_(2)Si_(2)O_(7)产生压应力,促进了裂纹愈合。SiC_(f)/SiC ceramic matrix composites meet the high thrust-to-weight ratio requirements of next-generation aeroengines but require environmental barrier coatings for protection under extreme high-temperature conditions.Current environmental barrier coatings inevitably develop cracks during service,necessitating self-healing coatings for autonomous crack repair.In this study,based on Yb_(2)Si_(2)O_(7),Yb_(2)Si_(2)O_(7)-SiC and Yb_(2)Si_(2)O_(7)-Yb_(2)SiO_(5)were fabricated via spark plasma sintering and pressureless sintering,respectively.The self-healing behavior of these composites was investigated to evaluate their feasibility as environmental barrier coating materials.Results show that adding 5wt%~10wt%SiC to Yb_(2)Si_(2)O_(7)promoted crack healing after 1 h at 1100℃in air,driven by SiO_(2)formation from SiC oxidation,which filled cracks through volume expansion.However,at 1300℃,excessive SiC oxidation caused significant volumetric stress,generating new cracks within the composites.Yb_(2)SiO_(5)addition enhanced material densification and crack healing.The composite with 50wt%Yb_(2)SiO_(5)achieved optimal healing efficiency(78%),attributed to thermally induced compressive stress from higher thermal expansion coefficient of Yb_(2)SiO_(5).This stress facilitated crack closure in the Yb_(2)Si_(2)O_(7)matrix.

关 键 词：Yb_(2)Si_(2)O_(7) 复合材料 自愈合 裂纹 环境障涂层 

分 类 号：TQ174.1[化学工程—陶瓷工业] TB332[化学工程—硅酸盐工业]