等离子喷涂法纳米结构WC-12Co涂层的微结构与形成机理的研究

Microstructure and Formation Mechanism of Nanostructured WC-12Co Coatings Deposited by Plasma Flame Spray

使用独特的雾化干燥结合固定床技术合成WC-12Co纳米复合粉体,利用等离子喷涂法制备纳米结构WC-12Co涂层,通过X射线衍射、扫描电镜、透射电镜等分析手段对等离子喷涂纳米结构WC-12Co涂层进行显微结构分析。结果表明涂层中除了WC相,不仅有W2C,W等非WC/Co相的产生,还出现了CoXWyCz(Co3W9C4,Co3W3C),Co3C等相及非晶和孪晶组织,在此基础上本工作将对等离子喷涂纳米结构WC-12Co涂层的形成机理作初步的研究与讨论。

The precursor of WC-12Co nano-composite powder is synthesized by the larruping method of spray drying and fixed bed technique, nanostructured WC-12Co cermet coatings are deposited by plasma flame spray. Microstructure of nanostructured WC-12Co cermet coatings is evaluated by using X-ray diffraction（XRD）, scanning electron microscopy（SEM） and transmission electron microscopy（TEM）. The nano-composite WC-12Co powders generally contain WC and Co, whereas the phases W2C, W and Co3C, Co3W9C4, Co3W3C/amorphous hinder phases based on Co and nano-twins occur in coatings, the mechanism of formation of nanostructured WC-12Co cermet coatings is discussed on the basis of the microstructure in this paper.