A novel route to enhance high-temperature mechanical property and thermal shock resistance of low-carbon MgO–C bricks by introducing ZrSiO4

• Published in: Journal of iron and steel research, international Vol. 31; no. 6; pp. 1436 - 1448
• Main Authors: Sun, Chun-hui, Zhu, Ling-ling, Yan, Hao, Zhao, Wei, Liu, Jing-xuan, Ren, Lin, Zhao, Xian-tang, Tong, Xiao-song, Yu, Shu-wen
• Format: Journal Article
• Language: English
• Published: Singapore Springer Nature Singapore 01.06.2024
• Subjects: Applied and Technical Physics; Engineering; Machines; Manufacturing; Materials Engineering; Materials Science; Metallic Materials; Original Paper; Physical Chemistry; Processes; ZrSiO; High-temperature mechanical property; Low-carbon MgO–C brick; Thermal shock resistance; Synergistic toughening effect; Vacuum oxygen decarburization ladle
• ISSN: 1006-706X; 2210-3988
• DOI: 10.1007/s42243-023-01063-8

Conventional MgO–C bricks (graphite content > 14 wt.%) produce a great deal of greenhouse gas emission, while low-carbon MgO–C bricks have serious thermal shock resistance during high-temperature service. To enhance the high-temperature mechanical property and thermal shock resistance of low-carbon MgO–C bricks, a novel route of introducing ZrSiO 4 powder into low-carbon MgO–C bricks was reported in such refractories with 2 wt.% flaky graphite. The results indicate that the low-carbon MgO–C brick with 0.5 wt.% ZrSiO 4 addition has the maximum hot modulus of rupture at 1400 °C and the corresponding specimen fired in the carbon embedded atmosphere has the maximum residual strength ratio (98.6%) after three thermal shock cycles. It is found that some needle-like AlON and plate-like Al 2 O 3 –ZrO 2 composites were in situ formed in the matrices after the low-carbon MgO–C bricks were coked at 1400 °C, which can enhance the high-temperature mechanical property and thermal shock resistance due to the effect of fiber toughening and particle toughening. Moreover, CO 2 emission of the newly developed low-carbon MgO–C bricks is reduced by 58.3% per ton steel after using them as the working lining of a 90 t vacuum oxygen decarburization ladle.