WC含量对铁基涂层非晶形成能力及其性能影响

Effect of WC Content on Amorphous Formation Ability and Coating Properties of Fe-based Amorphous Coatings

采用电弧喷涂技术喷涂不同WC含量的Fe基粉芯丝材,在Q235低碳钢基体上制备5种不同非晶含量的Fe基合金涂层。利用光学显微镜、透射电子显微镜、扫描电子显微镜和X射线衍射仪对涂层的显微组织结构、磨损表面及其相组成进行分析,用MLS–225型湿砂橡胶轮磨损试验机评价铁基复合涂层的磨粒磨损性能。结果表明,制备的几种涂层中均含有非晶相,当粉芯中WC质量分数在30%以内时,随着WC含量的增加,涂层中的非晶含量增加,相应涂层的硬度增加,耐磨性保持稳定;涂层的磨损机制主要为硬质相的脆性剥离和轻微的塑性切削,在磨粒磨损情况下硬度较低的金属基体先磨损,硬度高的Fe2B硬质相起到了阻止石英砂磨损的作用,从而降低了涂层的磨损。

Five types of Fe-based amorphous coatings were deposited on Q235 steel substrate by arc spraying cored wire with WC ceramic powders. The microstructure of the coating was investigated by optical microscopy and transmission electron microscopy. X-ray diffraction analysis was used to study the phase composition in the coating. The microhardness of the coating was determined. The wear behavior of the coating was evaluated. The results showed that all the coatings contained amorphous phase. The hardness of the coatings increases with increasing of the WC content in the cored wire （less than 30%） The wear resistance of the coatings will keep stable with increasing of the WC content in the cored wire （less than 30%）. The main wear mechanics of the coatings are brittle flaking off and micro-cutting. The metallic matrixes of the coatings, due to their low hardness, are worn prior to the hard phase. The higher hardness Fe2B phase plays a role to resist the abrasion from silica, and thus decreases the abrasion of the coatings