摘要
抗烧蚀性能是航空航天领域用超高温陶瓷(UHTCs)的重要使役性能,而激光烧蚀法是评价这类材料抗烧蚀性能的有效手段之一。高熵硼化物陶瓷是超高温陶瓷家族的新成员,了解其抗激光烧蚀性能和相关机理,对开发新型高性能超高温陶瓷具有重要意义。然而,当前还缺乏对高熵硼化物陶瓷抗激光烧蚀性能的明确了解。针对这一问题,本文采用波长为10.6μm、光斑直径2 mm的CO_(2)激光加热高熵硼化物(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))B_(2)(HEB)陶瓷和(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))B_(2)-20 vol%SiC(HEB-20SiC)复相陶瓷的表面,对比研究了两者的抗激光烧蚀性能,并着重考察了SiC第二相对HEB陶瓷高温氧化烧蚀行为的影响。结果显示,当激光功率密度达到57.3 MW/m^(2)并保持300 s时,HEB陶瓷的表面最高温度达到2256℃,线烧蚀速率为0.12μm/s,质量烧蚀速率为-0.014 mg/s;而在相同的激光烧蚀条件下,HEB-20SiC复相陶瓷的表面最高温度达到2168℃,线烧蚀速率为0.08μm/s,质量烧蚀速率为-0.007 mg/s,比HEB陶瓷的表面最高温度、线烧蚀速率和质量烧蚀速率的绝对值分别降低了~100℃、33.3%和50%。分析认为,由于HEB-20SiC陶瓷具有比HEB陶瓷更高的热导率,且SiC相氧化产生的SiO_(2)在高温下融化、蒸发带走了部分热量,有效地降低了样品表面的烧蚀温度,使得HEB-20SiC陶瓷表现出比HEB陶瓷更优异的抗激光烧蚀性能。
ablation resistance is a key property of ultra-high temperature ceramics(UHTCs)for application in aviation and aerospace.The laser ablation test is one of the effective methods to evaluate the ablation resistance of UHTCs.High-entropy diboride ceramics is a new member of the family of UHTCs,and it is of great significance to understand its laser ablation resistance and related mechanisms for the development of new high-performance UHTCs.However,the laser ablation resistance of highentropy diboride ceramics is not known clearly till now.In response to this problem,the laser ablation resistance of high-entropy diboride(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))B_(2)(HEB)ceramics and(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))B_(2)-20 vol%SiC(HEB-20SiC)composite ceramics have been investigated using a CO_(2)laser with wavelength of 10.6μm and spot diameter of 2 mm to heat the surface of the samples upto ultra-high temperatures in this work.The effect of the SiC secondary phase on the hightemperature oxidation and ablation behavior of HEB ceramics has been studied.It is found that the highest surface temperature,the linear ablation rate and the mass ablation rate of HEB composite ceramics after the laser powder density reached 57.3 MW/m^(2) and dwelled 300s are 2256℃,0.12μm/s and-0.014 mg/s,respectively.In contrast,under the same laser ablation test condition,the highest surface temperature,the linear ablation rate and the mass ablation rate of HEB-20SiC composite ceramics are 2168℃,0.08μm/s and-0.007 mg/s,respectively,which are lower than those of HEB ceramics by~100℃,33.3%and 50%.HEB-20SiC ceramics have higher thermal conductivity than HEB ceramics,and the SiO_(2)phase produced by the oxidation of the SiC phase melts and evaporates at high temperatures,which takes away part of the heat and consequently effectively reduces the ablation temperature on the surface of the samples so that HEB-20SiC ceramics show better laser ablation resistance than HEB ceramics.
作者
赵涛
刘吉轩
徐以祥
王靖媛
黄山松
牛亚然
张国军
ZHAO Tao;LIU Ji-Xuan;XU Yi-Xiang;WANG Jing-Yuan;HUANG Shan-Song;NIU Ya-Ran;ZHANG Guo-Jun(State Key Laboratory for Modification of Chemical Fibers and Polymer Materials,Institute of Functional Materials,College of Materials Science and Engineering,Donghua University,Shanghai 201620,China;Engineering Research Center of Advanced Glass Manufacturing Technology,Ministry of Education,Donghua University,Shanghai 201620,China;Key Laboratory of Inorganic Coating Materials CAS,Shanghai Institute of Ceramics,Chinese Academy of Sciences,Shanghai 200050,China)
出处
《现代技术陶瓷》
CAS
2024年第5期417-433,共17页
Advanced Ceramics
基金
国家重点研发计划(2021YFB3701400)
国家自然科学基金(52032001、52332003)
中央高校基本科研业务费专项资金(2232024G-07)。
关键词
高熵陶瓷
超高温陶瓷
硼化物
碳化硅
烧蚀
氧化
high-entropy ceramics
ultra-high temperature ceramics
boride
silicon carbide
ablation
oxidation
