Corrosion properties of amorphous, partially, and fully crystallized Fe68Cr8Mo4Nb4B16 alloy

Autor(es):Mostrar menos -

Coimbrao, D. D. ^[1] ; Zepon, G. ^[2] ; Koga, G. Y. ^[2] ; Godoy Perez, D. A. ^[1] ; Paes de Almeida, F. H. ^[1] ; Roche, V ^[3] ; Lepretre, J-C ^[3] ; Jorge Jr, A. M. ; Kiminami, C. S. ^[4] ; Bolfarini, C. ^[4] ; Inoue, A. ^{[5, 6, 7]} ; Botta, W. J. ^[4]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Carlos, Programa Posgrad Ciencia & Engn Mat, Rod Washington Luiz, Km 235, BR-13565905 Sao Carlos, SP - Brazil

^[2] Univ Fed Sao Carlos, Dept Engn Mat, Rod Washington Luiz, Km 235, BR-13565905 Sao Carlos, SP - Brazil

^[3] Univ Grenoble Alpes, Univ Savoie Mt Blanc, LEPMI, Grenoble INP, CNRS, F-38000 Grenoble - France

^[4] Jorge Jr, Jr., A. M., Univ Fed Sao Carlos, Dept Engn Mat, Rod Washington Luiz, Km 235, BR-13565905 Sao Carlos, SP - Brazil

^[5] Josai Int Univ, Int Inst Green Mat, Togane 2838555 - Japan

^[6] King Abdulaziz Univ, Dept Phys, Jeddah 22254 - Saudi Arabia

^[7] China Univ Min Technol, Inst Mass Amorphous Met Sci, Xuzhou 221116, Jiangsu - Peoples R China

• Tipo de documento: Artigo Científico
• Fonte: Journal of Alloys and Compounds; v. 826, JUN 15 2020.
• Citações Web of Science: 0

Resumo

In this work, the corrosion behavior of amorphous and partially crystallized Fe68Cr8Mo4Nb4B16 alloys has been studied. Fully amorphous ribbons were prepared by melt spinning and then partially and fully crystallized at different heat treatment temperatures. The corrosion behavior was evaluated in chloride-rich media at different pHs, ranging from acidic to alkaline. An exceptionally high corrosion resistance was observed for the new Fe68Cr8Mo4Nb4B16 amorphous alloy in the proposed media and pHs. The amorphous phase containing corrosion-resistant alloying elements such as chromium and molybdenum led to the formation of a highly stable passivating film, which coated and protected the active exposed metal surface. Partially crystallized samples heated up to 700 degrees C still grant the formation of a corrosion-resistant passivating layer. The presence of such a layer was correlated to the non-percolation of crystals embedded into the corrosion-resistant amorphous matrix. The corrosion resistance of fully crystalline annealed ribbons and as-cast ingots did not present the similar superior corrosion performance. This behavior was assigned to element partitioning throughout the crystallization, particularly chromium, which led to a non-homogeneous structure that preferentially triggered and held pitting corrosion along with the percolated crystalline material. These results indicate that the Fe68Cr8Mo4Nb4B16 alloy is a candidate for corrosion resistant coating where the suppression of crystallization is unavoidable. (C) 2020 Elsevier B.V. All rights reserved. (AU)

• Processo FAPESP: 13/05987-8 - Processamento e caracterização de ligas metálicas amorfas, metaestáveis e nano-estruturadas
• Beneficiário: Claudio Shyinti Kiminami
• Modalidade de apoio: Auxílio à Pesquisa - Temático