The influence of carbon content in the borided Fe-alloys on the microstructure of iron borides
- Poznan University of Technology, Institute of Materials Science and Engineering, Pl. M.Sklodowskiej-Curie 5, 60-965 Poznan (Poland)
- Technical University of Lodz, Institute of Materials Science and Engineering, Stefanowskiego St.1/15, 90-924 Lodz (Poland)
This paper presents the results of Electron Back-Scatter Diffraction (EBSD) analyses of the borided layers produced on substrate of varying carbon content. Two types of materials were investigated: borided Armco iron of very low carbon content and borocarburized chromium- and nickel-based steels of high carbon content beneath iron borides. The tetragonal phase Fe{sub 2}B was identified in all materials studied. It was difficult to obtain an EBSD pattern from iron boride (FeB) because of its presence at low depths below the surface, and because of the rounded corners of the specimens. EBSD provided information on the orientation of Fe{sub 2}B crystals. In case of the low-carbon Armco iron the crystallographic orientation was constant along the full length of the Fe{sub 2}B needle. The EBSPs obtained from borocarburized steel indicate that the crystallographic orientation of the Fe{sub 2}B phase changes along the length of the needle. This is the result of hindered boron diffusion due to boriding of the carburized substrate. The increased resistance to friction wear of borocarburized layers arises from two reasons. One is the decreased microhardness gradient between the iron borides and the substrate, which causes a decrease in the brittleness of the iron borides and an improved distribution of internal stresses in the diffusion layer. The second is the changeable crystallographic orientation of iron borides, which leads to the lower texture and porosity of borided layers. These advantageous properties of the borocarburized layer can be obtained if the carbon content beneath the iron borides is no more than about 1.0-1.2 wt.% C.
- OSTI ID:
- 20833199
- Journal Information:
- Materials Characterization, Vol. 56, Issue 3; Other Information: DOI: 10.1016/j.matchar.2005.11.013; PII: S1044-5803(05)00265-2; Copyright (c) 2005 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 1044-5803
- Country of Publication:
- United States
- Language:
- English
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