MoSi2涂层高温富氧火焰冲刷失效机理研究
Study on Failure Mechanism of MoSi2 Coating Under High-Temperature Oxygen-Enriched Flame Erosion
罗靖川 1朱昌发 2刘坤 2王钺淞 3徐向毅 4杨冠军 1陈林1
作者信息
- 1. 西安交通大学 金属材料强度国家重点实验室, 陕西 西安 710049
- 2. 中国航天西安航天发动机有限公司, 陕西 西安 710065
- 3. 火箭军装备部驻西安地区第二军事代表室, 陕西 西安 710065
- 4. 空军装备部驻西安地区军事代表局第八军事代表室, 陕西 西安 710065
- 折叠
摘要
MoSi2 高温氧化时表面可生成保护性SiO2,有望用于推力室喷管内表面抗高温氧化涂层材料.然而,在 1800℃及以上超高温火焰冲刷考核条件下,MoSi2 涂层发生快速损伤失效.为揭示MoSi2 涂层超高温冲刷失效机理,系统研究了推力室喷管不同位置涂层的氧化行为和损伤规律.结果表明:涂层损伤分为 5 个特征区域,分别为前缘、喉部、过渡段、中部和尾部,其中喉部发生整个涂层剥落,尾部涂层仍保持完整.MoSi2 涂层的主要失效形式为:超高温下MoSi2 涂层晶界快速氧化和氧化膜快速挥发,产生晶界裂纹,晶界裂纹合并形成网状、贯穿性、大尺度的纵向裂纹,将MoSi2 涂层分割成岛状区域.在热冲击载荷作用下,岛状区域MoSi2 涂层发生剥落失效.指出了MoSi2 涂层超高温冲刷腐蚀机理,为发展推力室喷管用长寿命MoSi2 超高温抗氧化涂层提供了理论方向.
Abstract
MoSi2 can generate protective SiO2 on the surface during high temperature oxidation,which is expected to be used as a high-temperature oxidation-resistant coating on the inner surface of the thrust chamber nozzle.However,the MoSi2 coatings failed under the flame erosion at temperatures≥1800℃.In order to reveal the failure mechanism of MoSi2 coat-ings,the oxidation behavior of coating at various locations of the thrust chamber nozzle specimen after the flame erosion was clarified.The results show that the coating can be divided into five characteristic regions,namely the lead-ing edge,the throat,the transition section,the middle and the tail.Among them,the entire coating peels off at the throat,and the coating remains intact at the tail.The main failure mode of the MoSi2 coatings is:rapid oxidation and corrosion at the grain boundaries(GB)of the MoSi2 coat-ings result in the formation of penetrating GB cracks,the coalescence of penetrating GB cracks causes the connected and large-scale vertical cracks,dividing the coatings into island-shaped regions.Under the action of thermal shock,island-shaped coatings peel off.This research analyzes the erosion behavior of MoSi2 coating,and provides the reference for the development of long-life ultra-high temperature anti-oxidation MoSi2 coatings for thrust chamber nozzles.
关键词
MoSi2涂层/氧化膜/晶界/纵向裂纹/剥落Key words
MoSi2 coating/oxide film/grain boundary/vertical cracks/transverse spallation引用本文复制引用
基金项目
中国博士后科学基金创新人才支持计划(BX2021238)
国家自然科学基金(51671159)
出版年
2024
NETL
NSTL
万方数据