超音速火焰喷涂低碳WC/12Co涂层的组织及性能研究

采用离心雾化干燥法制得团聚颗粒,经连续高温烧结成两种不同松装密度的热喷涂粉末。采用以C3H8/O2为燃料的超音速火焰喷涂（HVOF）工艺制备了WC/12Co涂层。对粉末及涂层做了显微组织观察和XRD分析,测定了涂层的厚度、显微硬度和粉末沉积效率。结果表明,在1120℃、1180℃烧结的粉末中主要有WC和W6Co6C,但无Co相;涂层有脱碳,有Co6W6C相,但未出现单质Co。涂层组织均匀致密,沉积效率可达65%。

Microstructure and Performance of Low Carbon WC/12Co Coatings Prepared by HVOF Spraying

Agglomerated particles were prepared by centrifugal atomization,and continuously sintered at high temperature thus became two types of thermal spraying powder with defferent apparent densities.The WC/12Co coating was prepared by HVOF spraying process using C3H8/O2 as fuel.The microstructure examination of the powders and XRD analysis of the coating were performed,and the thickness,microhardness and powder deposition efficiency were measured.The results indicate that there are WC and W6Co6C but not Co phase in the powder sintered at 1120 ℃and 1180 ℃,and that there are decarburization and W6Co6C but not elemental Co in the coating.The structure of the coating is uniform and dense,with the deposition efficiency being up to 65%.