Al_2O_3复相陶瓷涂层的SHS反应火焰喷涂过程

Investigation on Process of SHS Reactive Flame Spraying Al_2O_3 Multiphase Ceramic Coatings

基于自蔓延高温合成技术(SHS)的反应火焰喷涂技术,用氧–乙炔火焰引燃Al–CuO团聚粉,使之发生自蔓延反应,在钢基表面制备了Al2O3复相陶瓷涂层。通过水淬熄试验截取飞行粒子的中间状态,对经水冷后的粒子及喷涂涂层进行物相与组织分析,从而给出了SHS反应火焰喷涂Al2O3复相陶瓷涂层的基本过程,即各团聚颗粒构成独立的微小反应单元,经历Al熔化和CuO分解的反应孕育、Al与Cu2O的飞行反应燃烧、与基体碰撞并继续反应、结构转变与凝固4个阶段,最终形成Al2O3复相陶瓷涂层。

Using SHS Reactive Flame Spraying (RFS) technology, an Al2O3 multi-phased ceramic coating was prepared on iron substrate with Al and CuO as main reactants, the SHS process was ignited by oxyacetylene flame. The state of water-quenching agglomerated particles at different distance, phase constituent and microstructure of the coatings were observed and analyzed. The process of SHS RFS Al2O3 multi-phased ceramic coating was studied. It was found that during the spraying process, the agglomerated particles, acting as independent reactive units, went through four successive stages: Al melted and CuO decomposed, Al and Cu2O reacted, they collided with iron substrate and continually reacted, and structure transformed and solidified, finally the Al2O3-Based multi-phased ceramic coating was completed.