About this Abstract |
Meeting |
MS&T25: Materials Science & Technology
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Symposium
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Engineering Ceramics: Microstructure-Property-Performance Relations and Applications
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Presentation Title |
Reduction Behavior of Mullite/Andalusite-Based Refractories Under Hydrogen Atmosphere and the Effect of Crystalline SiO2 on Mechanical Strength |
Author(s) |
Sung-Hyun Kim, Jong-Won Woo, Jong-Won Kim, Sang-Min Hong, Eun-Hee Kim, Rae-Hyeong Park, Sang-Bae Choi, Sang-Chae Jeon |
On-Site Speaker (Planned) |
Jong-Won Kim |
Abstract Scope |
Due to the high CO2 emissions from conventional coke-based steelmaking, hydrogen-based reduction is gaining attention as a sustainable alternative. To enable hydrogen reduction, refractories must remain intact even at high temperatures under severely reducing atmospheres. This study examines the reduction behavior of widely used mullite/andalusite-based refractories to evaluate their applicability in the hydrogen reduction process. After heat treatment at 1100 °C for 72 hours in 100% hydrogen, variations of the refractory samples were investigated. As a result, fracture strength decreased from 3.19 to 2.15 MPa due to reduction-induced volatilization of silica, i.e., the formation of gaseous SiO and H2O. This was supported by a reduction in weight and the presence of voids remaining at particle interfaces after the reduction heat treatment. In addition, Fe2O3 and TiO2 were believed to be reduced, resulting in darker colors. These findings provide guidance for the compositional design of refractories for use in hydrogen reduction processes. |