Preparation of Cr₂O₃-Al₂O₃-Cr Coatings on Carbon Steel by Aluminothermic Process Based on Cr₂O₃ and Al System

Abstract:

In the present work, Cr₂O₃-Al₂O₃-Cr coatings are prepared on Q235 steel by aluminothermic process based on Cr₂O₃ Al system, using Cr₂O₃ as diluents while a small quantity of Fe₂O₃ to reduce reaction temperature. The results showed that after treated at 650oC for 30minutes, homogenous Cr₂O₃-Al₂O₃-Cr coatings can be prepared on Q 235 steel by aluminothermic process with the powders mixture with weight ratio of Cr₂O₃: Fe₂O₃: A1 equal to 4: 0.3: 1.12, while coatings prepared by mixture with superfluous aluminum are fragmentary. Surface hardness of the coatings prepared with superfluous Cr₂O₃ is about 23.9GPa while that of the coatings prepared with superfluous Al is about 10.9 GPa and large scatter of 13.7% in hardness.

• Periodical: Advanced Materials Research (Volumes 774-776)
• Pages: 560-563
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.774-776.560
• Online since: September 2013
• Authors: Hong Zhou, Shou Jun Wu, Shuang Liu, Yan Shen, Bao Shan Yang, Xu Zheng
• Keywords: Aluminothermic Process, Coating, Cr₂O₃-Al₂O₃-Cr, Hardness, Q 235 Steel

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