Refinement of nano-Y2O3 on microstructure of hypereutectic Fe-Cr-C hardfacing coatings

• Published in: Journal of rare earths Vol. 33; no. 6; pp. 671 - 678
• Main Author: 员霄 周野飞 杨健 邢晓磊 任学军 杨育林 杨庆祥
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.06.2015
• Subjects: hardfacing misfit; hypereutectic Fe-Cr-C coatings; nano-Y2O3; primary M7C3; rare earths; Y203; 场发射扫描电子显微镜; 微观结构; 涂层制备; 纳米Y2O3; 组织细化; 耐磨堆焊; 过共晶; nano-Y2O3; hypereutectic Fe-Cr-C coatings; primary M7C3; hardfacing misfit; rare earths
• ISSN: 1002-0721; 2509-4963
• DOI: 10.1016/S1002-0721(14)60469-5

The Fe-Cr-C flux-cored wires with 0 wt.%, 0.63 wt.%, 2.54 wt.% and 5.08 wt.% additions of nano-Y203 were developed in this work. And the different hypereutectic Fe-Cr-C hardfacing coatings were prepared. The phase structures of the coatings were determined by X-ray diffraction. The microstructures were observed by optical microscopy. The morphologies of the hypereutectic Fe-Cr-C hardfacing coatings were observed by a field emission scanning electron microscope equipped with an X-ray energy disper- sive spectrometer. The effectiveness ofY203 as heterogeneous nuclei of primary M7C3 was calculated with the misfit theory. The ex- periment results showed that, the microstructures of the hypereutectic Fe-Cr-C hardfacing coatings consisted of M7C3, ？-Fe and a-Fe phases. With the increase of nano-Y203 additives, primary M7C3 in hypereutectic Fe-Cr-C coatings could be refined gradually. The average size of the primary M7C3 was the minimum, which was 22 pro, when nano-Y203 additive was 2.54 wt.%. The calculated re- sults showed that, the two-dimensional lattice misfit between the face （001） of Y203 and face （100） of orthorhombic M7C3 was 4.911%, which indicated that Y203 as heterogeneous nuclei of M7C3 was middle effective to refine the primary M7C3.