Volume 39, Issue 4 (Journal of Advanced Materials-Winter 2021)                   jame 2021, 39(4): 23-44 | Back to browse issues page

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1. Department of Mechanical Engineering, Persian Gulf University, Boshehr, Iran. 2. Department of Materials Engineering, Isfahan University of Technology, Isfahan, Iran. , n.hosseini@pgu.ac.ir
Abstract:   (562 Views)
The bare and pre-oxidized AISI 430 pieces were screen printed by copper ferrite spinel coatings. Good bonding between the coating and the substrate was achieved by the reactive sintering process of the reduced coating. The energy dispersive X-ray spectroscopy (EDS) analysis revealed that the scale is a double layer consisting of a chromia-rich subscale and an outer Cu/Fe-rich spinel. The results showed that the spinel protection layer not only significantly decreased the area specific resistance (ASR), but also inhibited the subscale growth by acting as a barrier to the inward diffusion of oxygen. ASRs of 19.7 and 32.5 mΩ.cm2, much lower than that of the bare substrate (153.4 mΩ.cm2), at 800 °C after 400 h oxidation were achieved for the bare and pre-oxidized copper ferrite spinel coated samples, respectively. Excellent, stable ASR (20.5 mΩ.cm2) was obtained with copper ferrite coating after 600 h of exposure at 800 °C. The high electrical conductivity of CuFe2O4 and its doping by Mn, the growth reduction of Cr2O3 oxide scale and the good coating to substrate adherence are proposed to be responsible for substantial improvement in electrical conductivity.
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Type of Study: Research | Subject: Surface engineering and coatings
Received: 2019/04/22 | Accepted: 2020/12/9 | Published: 2020/12/20