Effects of andalusite aggregate pre-fired at different temperatures on volume stability and oxidation resistance of Al2O3–SiC–C castables. Issue 14 (1st October 2020)

• Record Type: Journal Article
• Authors: Tian, Xuekun; Liu, Mingyang; Luan, Jian; Zhu, Lingling; Zhao, Jizeng; Ye, Guotian
• Is Part Of: Ceramics international. Volume 46:Issue 14(2020)
• Page Start: 22745
• Page End: 22751
• Publication Date: 2020-10-01
• Subjects: Andalusite -- Pre-firing -- Al2O3–SiC–C castables -- Oxidation resistance -- Volume stability; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2020.06.041
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: In the present work, the effects of the pre-firing temperature of andalusite aggregates (5–3 mm) on the conversion of andalusite as well as the volume stability and oxidation resistance of the Al2 O3 –SiC–C castables were investigated. The phases of the andalusite aggregates were tested via X-ray diffraction, and their microstructures as well as those of the castables were characterized via scanning electron microscopy. The linear expansion of the castables decreased with increase in the pre-firing temperature of andalusite, as less residual andalusite in the pre-fired aggregates lowered its transformation in the castables during firing at high temperatures. Moreover, the higher amounts of SiO2 -rich glass produced by andalusite pre-fired at high temperatures and secondary mullite generated between andalusite and the matrixes were both favorable to the production of castables with denser structure. This prevented the diffusion of O2 into the castables and improved their oxidation resistance.