等离子喷涂Cr2O3-TiO2基高发射率涂层微观结构及性能研究

摘要

Cr2O3-TiO2-based composite powder with spinel structure is prepared by spray drying and sintering densification treatment, using the raw materials of chromium oxide, titanium oxide, nickel oxide and rare earth oxide. The Cr2O3-TiO2-based high emissivity coating is deposited on the titanium alloy substrate by atmospheric plasma spraying. The microstructure, bond strength, thermal shock resistance and radiation performance are investigated. The results of experimental investigation indicate that: the porosity of Cr2O3-TiO2-based high emissivity coating is low than 3%, the bond strength reaches 33.1MPa, and the normal total emissivity is about 0.88~0.89 under 400~800℃. Besides, no cracks and spalling failure occurr after thermal shock testing by water quenching from 600 degrees to room temperature by 30 times, showing good thermal shock resistance.%本文以Cr2O3、TiO2、NiO、稀土氧化物为原料，经喷雾干燥及烧结致密化处理制备成具有尖晶石结构的Cr2O3-TiO2基复合团聚型粉体，采用大气等离子喷涂在钛合金表面制备了Cr2O3-TiO2基高发射率涂层，分析测试了涂层显微组织结构、结合强度、抗热震性能及辐射性能。研究结果表明：所制备的Cr2O3-TiO2基高发射率涂层孔隙率为1.51%，结合强度达33.1MPa，在400~800℃温度范围内，其法向全发射率可达0.88~0.89；涂层经600℃至室温热震30次后未发生开裂、剥落现象，涂层抗热震性能良好。