喷涂工艺参数对铝硅氮化硼封严涂层组织及性能的影响

采用大气等离子喷涂方法制备了铝硅氮化硼封严涂层,通过对涂层显微结构、硬度、结合强度和飞行粒子状态的研究,分析了喷涂工艺参数(功率22～34kW、送粉量30～50g/min及喷涂距离90～150mm)的变化对涂层组织和性能的影响规律。研究结果表明:随着功率的增加,飞行粒子温度和速度均增加,涂层的孔隙率和BN含量降低,硬度和结合强度提高;随送粉量增加,粒子温度和速度均减小,涂层孔隙率和BN含量增加,硬度和结合强度降低;随着喷涂距离的增加,粒子飞行速度降低的影响大于温度升高的影响,导致涂层孔隙率和BN含量提高,硬度和结合强度降低。

Influence of Spray Process Parameters on Microstructure and Propertiesof AlSi-hexagonal Boron Nitride Abradable Seal Coating

Aluminum silicon hexagonal boron nitride abradable seal coatings were deposited using the Atmospheric Plasma Spraying (APS) process under several processing conditions. In the present paper, the effects of process parameters, such as spray power, feed rate, and spray distance, on the coating of microstructure and properties have been investigated. The micro-structure, hardness, bonding strength and chemical composition of these coating and flying particles process of the powders were researched. The results showed that with the increasing feed rate of powder, the temperature and the speed of the flying particles were increased, the porosity and BN content of the coating were reduced, and the hardness and bonding strength were improved. However, compared with the spraying power, the effect of the feed rate was in opposite directions. With the increase of spraying distance, the influence of particle flight velocity was greater than that of temperature rise, which results in the porosity and BN content of the coating increased, and the hardness and bonding strength of the coatings were also reduced.