针对液氧煤油发动机推力室铜合金喷管与高温富氧燃气导管对高结合强度与抗氧化及烧蚀防护涂层的迫切需求，本项目提出采用热喷涂制备两类具有低热导强氧化膜形成能力镍基合金涂层、并可与自生陶瓷氧化膜构成隔热涂层体系的热防护涂层设计；针对铜基喷管表面传统合金喷涂层与高温合金燃气导管表面涂层结合强度低的难题，提出通过Mo包覆NiCrCu与Ni-Al复合粉末设计、采用等离子喷涂获取超高温熔滴与碰撞自粘结效应的思路，研究超高温熔滴形成控制机制、影响熔滴与基体间结合形成的关键因素与结合形成机制，发展喷涂与热处理工艺结合显著提升合金涂层与合金结合强度、自生保护性氧化膜的制备方法；研究阐明NiCrCuMo/NiCrAlYX与NiAl基涂层成分、组织与性能、高温演变与氧化烧蚀的控制机制，发展热处理与氧化膜结构一体化控制工艺，为合金防护涂层制备提供依据；研究阐明合金涂层体系与自生氧化膜在高温服役条件的演变及其对涂层体系失效的控制因素与影响机制，为液氧煤油火箭发动机喷管等离子喷涂制备高性能长寿命防护涂层提供依据。

The design and preparation of a protective coating systems for oxygen-rich combustion flame conduit and copper-based nozzle with high bonding strength and high resistance of oxidation and ablation are the key issues for development of of high pressure chamber nozzle for liquid oxygen kerosene rocket engines. In this project two types of thermal spray nickel-based alloy coatings are strategically proposed, along with YSZ thermal barrier coating on the alloy coatings as the bond coat. Facing the common difficulty of low adhesive strength for thermal-sprayed alloy coatings on copper alloy and superalloy substrates, it is proposed to develop metallurgical self-bonding effect by creating ultra-high temperature droplets generated by plasma spraying using Mo-clad NiCrCu and Ni-Al based composite powders. The controlling factors influencing generation of ultra-high temperature droplet and bonding formation between alloy substrate and coatings will be investigated to clarify the bonding formation mechanisms. Then, a methodolgy to enhance adhesive strength of nickel based alloy coating will be developed through combining optimized spray conditions with post-spray annealing treatment. The effects of coating compositions, microstructure, and coating design on the resistance of high temperature oxidation and thermal cycling lifetime will be studied for Mo-NiCrCu/NiCrAlYX and NiAl based coatings to provide guidelines for design and deposition of high performance high temperature protective coating for both superalloy flame conduit and copper nozzle. Meanwhile, the evolution behaviors of Ni-based alloys and oxide coatings formed on Ni-based alloy surfaces under high temperature service conditions and their effect on possible spalling and subsequent failure mechanisms of coatings will be investigated. The thermal protection mechanism and failure behavior of the coating systems will be clarified. The achievements of this project should provide an important guidance for the design and fabrication of high performance and durable protective coatings for the liquid oxygen kerosene rocket engines.