(1. 湖南科技大學(xué) 先進(jìn)材料制備及應(yīng)用技術(shù)研究所，湘潭 411201；
2. 中南大學(xué) 粉末冶金國家重點實驗室，長沙 410083；
3. 廈門理工學(xué)院 材料科學(xué)與工程系，廈門 361024)
摘 要: 為了改善K403鎳基高溫合金的高溫抗氧化性能，采用大氣等離子噴涂在鎳基合金表面制備了4種不同結(jié)構(gòu)的MoSi2復(fù)合涂層。結(jié)果表明：4種結(jié)構(gòu)涂層中K403/NiCoCrAlY/ZrO2/30%(體積分?jǐn)?shù))ZrO2-MoSi2/MoSi2復(fù)合涂層的抗熱震性能最好，且該涂層的界面結(jié)合強(qiáng)度最高(22.5 MPa)。MoSi2涂層的自身結(jié)合強(qiáng)度大于涂層界面結(jié)合強(qiáng)度，結(jié)合機(jī)理以機(jī)械咬合式為主。該復(fù)合涂層在1 200 ℃氧化120 h后的質(zhì)量增加僅為3.42 mg/cm2，提高K403合金和傳統(tǒng)氧化鋯涂層的抗氧化性能。MoSi2復(fù)合涂層表面在高溫時生成了一層致密的SiO2保護(hù)膜，阻礙了氧的擴(kuò)散，減輕了過渡層NiCoCrAlY/ZrO2界面處的氧化。
關(guān)鍵字: 鎳基合金；二硅化鉬；復(fù)合涂層；組織；性能
（1. Advanced Materials Synthesis and Application Technology Institute,
Hunan University of Science and Technology, Xiangtan 411201, China;
2. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China;
3. Department of Material Science and Engineering, Xiamen University of Technology, Xiamen 361024, China）
Abstract:In order to improve the oxidation resistance of nickel-based alloy at high temperature, four kinds of MoSi2 composite coatings were successfully prepared on the nickel-based alloys surface by air plasma spraying. The results indicate that the thermal shock resistance and the adhesion strength (22.5 MPa) of K403/NiCoCrAlY/ZrO2/30%(volume fraction)ZrO2-MoSi2/MoSi2 composites coating are the best among the four kinds of coatings. The self-bonding strength of MoSi2 coating is greater than the interfacial bond strength of the composites coating, and the bond mechanism is mechanical bond with bite combination. The mass increment is only 3.42 mg/cm2 when MoSi2 composites coating is oxidized at 1 200 ℃ for 120 h. Compared with the nickle-based alloy and the conventional thermal barrier coating, the oxidation resistance of the MoSi2 composites coating is improved. During the high-temperature oxidation process, a dense SiO2 layer is formed on the surface of the MoSi2 coating，which hinder the diffusion of oxygen. The oxidation degree of the boundary between the NiCoCrAlY and zirconia ceramic is relieved.
Key words: nickel-based alloy; molybdenum disilicide; composites coating; microstructure; properties
