反应等离子喷涂Fe-Ti-C复合粉末制备金属陶瓷涂层的组织形成机理  

Microstructure Forming Mechanism of Cermet Coatings Prepared by Reactive Plasma Spraying of Fe-Ti-C Powders

作　　者：王海涛[1] 张守全[1,2] 黄继华[1] 朱警雷[1] 张强[1] 张华[1] 

机构地区：[1]北京科技大学材料科学与工程学院材料加工系,北京100083 [2]厦门金鹭特种合金有限公司,福建厦门361006

出　　处：《航空材料学报》2009年第4期42-46,共5页Journal of Aeronautical Materials

摘　　要：以蔗糖为碳的前驱体、TiFe粉为原料制备Fe-Ti-C系反应热喷涂复合粉末,通过等离子喷涂沉积TiC/Fe金属陶瓷涂层,利用"淬熄试验"研究涂层组织形成机理。采用XRD和SEM分析喷涂粉末、涂层以及淬熄粒子的组织结构。结果表明:每个复合粉末团粒构成独立的反应单元,在喷涂飞行过程中首先出现Ti-Fe液相,然后整个团粒发生球化;熔化的团粒内部生成大量细小TiC颗粒,表层有少量TiC聚集,与基板碰撞后形成复合强化片层与TiC聚集片层交替叠加的涂层结构;随飞行距离增大,团粒外部TiC聚集层增厚,内部TiC颗粒减少,碰撞扁平化程度降低;最终涂层由TiC和Fe两相组成,大量亚微米级TiC颗粒呈内晶型均匀分布于Fe基体中。TiC/Fe cermet coatings were prepared by reactive plasma spraying of Fe-Ti-C powder,which used sucrose as carbonaceous precursor and ferrotitanium as raw materials. Quenching test was employed to investigate microstructure forming mechanism of the coatings. Microstructure of the composite powders, coatings and quenched products were analyzed by XRD and SEM. It is shown that every granule of the composite powders acts as a reactive unit. Ferrotitanium melt firstly, then the whole granule. Lots of TiC particles are formed inside the granule and some agglomerate outside. These granules collide onto substrate to form the coatings with superposition of composite layers and agglomerated TiC. As flight distance increases, the outside agglomerated TiC increases and the inside TiC particles decrease, so the granule is more difficult to form layer after impinging onto the substrate. Finally, the coatings are composed of both TiC and Fe, and a number of TiC particles are uniformly distributed inside crystal grains of Fe matrix.

关 键 词：TiC/Fe金属陶瓷涂层 Fe-Ti-C复合粉末 组织形成机理 

分 类 号：TB333[一般工业技术—材料科学与工程]