摘要
在服役环境中,超高声速飞行器表面与空气剧烈摩擦导致温度极高。超高温陶瓷相较于一般陶瓷而言具有高熔点和良好的抗氧化烧蚀性能,是目前极具前景的热防护材料之一。采用放电等离子两步烧结工艺将ZrB2纳米粉末和SiC粉末在1700℃下制备超高温陶瓷材料ZrB2-20%SiC,通过纳米压痕微观实验、三点弯实验研究其力学性能及其在高温环境下的氧化行为,着重分析1000、1200、1400和1600℃4种不同氧化温度下ZrB2-20%SiC超高温陶瓷的氧化表面、氧化截面和氧化层厚度。结果表明:ZrB2-20%SiC超高温陶瓷的硬度为18 GPa,弹性模量为541 GPa,断裂韧性为5.7 MPa·m1/2;当氧化温度为1600℃时,超高温陶瓷内部的SiC由被动氧化转变为主动氧化,并且随着氧化温度升高,超高温陶瓷氧化层厚度与氧化温度呈正相关。
In the application environment,the surface of the ultra-high-speed aircraft is violently rubbed with the air to make the temperature extremely high.Compared with ordinary ceramics,ultra-high temperature ceramics possess a higher melting point with good oxidation and ablation resistance performance.Therefore,it is particularly interested to be used as thermal protection materials.In this paper,ZrB2-20%SiC ultra-high temperature ceramic materials are prepared by using the spark plasma two-step sintering process of ZrB2 nanopowder and SiC powder at 1700℃.The mechanical properties of ZrB2-20%SiC are studied through nanoindentation experiment and three-point bending experiment.The oxidation behavior of ZrB2-20%SiC ultra-high temperature ceramics at four different oxidation temperatures of 1000,1200,1400 and 1600℃is analyzed in this paper.The results show that the hardness of the ZrB2-20%SiC ultra-high temperature is 18 GPa,and the elastic modulus is 541 GPa with the fracture toughness of 5.7 MPa·m1/2.When the oxidation temperature is 1600℃,the SiC inside the ultra-high temperature ceramic would transform from passive oxidation to active oxidation.As the oxidation temperature increases,the thickness of the ultra-high temperature ceramic oxide layer and the oxidation temperature demonstrate a positive correlation trend.
作者
何慧娟
闫晓杰
树学峰
肖革胜
郝鑫
李志刚
HE Huijuan;YAN Xiaojie;SHU Xuefeng;XIAO Gesheng;HAO Xin;LI Zhigang(Institute of Applied Mechanics,College of Mechanical and Vehicle Engineering,Taiyuan University of Technology,Taiyuan 030024,Shanxi,China)
出处
《高压物理学报》
CAS
CSCD
北大核心
2021年第2期62-69,共8页
Chinese Journal of High Pressure Physics
基金
国家自然科学基金(11772217,11802198)。
作者简介
何慧娟(1995-),女,硕士研究生,主要从事弹塑性力学研究.E-mail:1945106146@qq.com;通信作者:李志刚(1975-),男,副教授,主要从事弹塑性力学研究.E-mail:254970134@qq.com。
