Microstructure and Wear Performance of Cobalt-Containing Iron-Based Slag-Free Self-shielded Flux-Cored Wire

Journal Article · Mon Apr 01 04:00:00 EDT 2019 · Journal of Materials Engineering and Performance

DOI:https://doi.org/10.1007/S11665-019-04002-5· OSTI ID:22970835

Liu, Dashuang ^[1]; Long, Weimin ^[2]; Wu, Mingfang ^[1]; Li, Leijun ^[3]; Wang, Jiayou ^[1]; Zhang, Yu ^[4]

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1. Jiangsu University of Science and Technology, School of Material Science and Engineering (China)
2. Zhengzhou Research Institute of Mechanical Engineering Co., Ltd. (China)
3. University of Alberta, Department of Chemical and Materials Engineering (Canada)
4. Sha-steel, Institute of Research of Iron and Steel (China)

A new type of cobalt-containing iron-based slag-free self-shielded flux-cored wire was developed for hardfacing. The influence of cobalt additions on the microstructure and wear performance of the hardfacing was investigated. The cobalt-containing iron-based hardfacing alloy has a typical hypereutectic microstructure consisting of primary M{sub 7}(C, B){sub 3} carbide, and a eutectic of M{sub 3}(C, B) carbide and austenite (part of which subsequently transformed into martensite). Cobalt promoted the formation of austenite and changed the morphology of the primary carbide and eutectic colonies. The morphology of primary carbide became fragmented with increasing cobalt due to the possible impeding effect of cobalt to the movement of the M{sub 7}(C, B){sub 3}/liquid interface. Different structures of the eutectic carbides were observed—the chrysanthemum structure for 1.42 wt.% cobalt, the skeleton form for 2.88 wt.% cobalt, the radial stripe 4.37 wt.% cobalt and the discrete stripe for 5.75 wt.% cobalt. Wear loss of the hardfacing alloy containing 2.88 wt.% cobalt was the smallest among all the alloys, owing to the large primary large carbide and skeleton-shaped eutectic carbides, the proper amount of austenite phase separating the M{sub 7}(C, B){sub 3} and M{sub 3}(C, B) carbides, the solid solution strengthening by cobalt in the matrix, and the high hardness of the alloy. Moreover, the wear resistance has a tendency to decrease with the increase in velocity as well as load.

• OSTI ID: 22970835
• Journal Information: Journal of Materials Engineering and Performance, Journal Name: Journal of Materials Engineering and Performance Journal Issue: 4 Vol. 28; ISSN 1059-9495; ISSN JMEPEG
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
AUSTENITE
BORON ALLOYS
BORON CARBIDES
COBALT ADDITIONS
EUTECTICS
IRON
MARTENSITE
MICROSTRUCTURE
SOLID SOLUTIONS
WEAR RESISTANCE