Original Article

Growth mechanism of Al₂O₃ on surface of ZrO₂ inclusions: experimental and first principles investigation

¹ School of Materials and Energy Engineering, Guizhou Institute of Technology, Guiyang, Guizhou 550025, PR China
² School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, PR China
³ School of Materials and Metallurgy, Guizhou University, Guiyang, Guizhou 550025, PR China

^* e-mail: lzwang@gzu.edu.cn

Received: 3 July 2024
Accepted: 24 August 2024

Abstract

Zr has been widely used in high-quality steel due to its strong deoxidizing capacity and ability of improve performance of steel. ZrO₂–Al₂O₃ inclusions with core-shell structure were observed in this study. The structure, electronic properties, and energy changes of ZrO₂ and ZrO₂–Al₂O₃ systems were studied based on first principles calculation. It indicates that ZrO₂ can be used as the heterogeneous nucleation core of Al₂O₃. Al atoms were preferentially adsorbed on the bridge site of ZrO₂ (001) and then form the ZrO₂–Al₂O₃ interface. The template effect of ZrO₂ was nine adsorption atomic layers, among which layers 1–5 was a coherent epitaxial layer, layers 5–9 was the transition layer, and the atomic ratio was 3:2. The growth mechanism of Al₂O₃ on ZrO₂ surface was discussed. The results help understand the formation of inclusion at atomic scale and find ways to control the characteristics of inclusion in steel with Zr treatment.