Corrosion of MgO-Cr refractory by PbO-rich copper slags by various corrosion methods [Abstr.] / lona Jastrzębska, Maciej Ludwig, Adam Piwowarczyk, Edyta Śnieżek, Yawei Li, Jacek Szczerba // W: ICC9 ... więcej

Corrosion of MgO-Cr refractory by PbO-rich copper slags by various corrosion methods [Abstr.] / lona Jastrzębska, Maciej Ludwig, Adam Piwowarczyk, Edyta Śnieżek, Yawei Li, Jacek Szczerba // W: ICC9 : Ceramics in Europe 2022 Conference Kraków, Poland, 10-14 July 2022 : abstract book [Dokument elektroniczny] / ed. Zbigniew Pędzich ; org. European Ceramic Society. – Mons, Belgium : European Ceramic Society, 2022. – S. 520. – Tryb dostępu: https://www.ceramicsineurope2022.org/conf-data/icc2022/files/abstracts.pdf. – ISBN 978-83-942760-9-6

For decades, magnesia-chromite (MgO-Cr) refractories are indispensable materials for linings in the heating devices of Cu and Pb metallurgy. They contain mainly MgO and up to 50 wt.% Cr2O3, MgO. However, ... więcej

For decades, magnesia-chromite (MgO-Cr) refractories are indispensable materials for linings in the heating devices of Cu and Pb metallurgy. They contain mainly MgO and up to 50 wt.% Cr2O3, MgO. However, the formation of chromium (VI) compounds at elevated temperatures requires searching for alternative Cr-free refractories. In order to achieve this, comprehensive knowledge of the chemical resistance of currently used refractories is essential. The refractory used in the work was a direct-bonded MgO-Cr commercial refractory product. The three chemically different PbO-rich copper slags were applied for the corrosion of MgO-Cr refractory. The corrosion was conducted by: hot stage microscopy, pellet and contact corrosion test. The corrosion results were interpreted by XRD and SEM/EDS. The SEM images of corroded materials were analyzed using developed recognition and object detection algorithms. In the work, we show that increased PbO content in the slag is responsible for intense microstructure disintegration of the MgO-Cr refractory when compared to CuOx. The general mechanism responsible for corrosion of material is as follows: The PbO-rich copper slag fully infiltrates the refractory through the open pores/cracks. This infiltration directly influences the weakening of magnesia-chromite solid solution direct bonds, and is followed by dissolution of chromite and magnesia grains, and subsequent formation of forsterite – the main new corrosion product that increases the volume of the refractory leading to the material swelling.