Preparation and properties of novel multi-component refractory cementitious materials

• Published in: Construction & building materials 2023-08, Vol.393, p.132033, Article 132033
• Main Authors: Wang, Caihui, Xu, Chenxi, Li, Wenhao, Xiao, Haijun, Qin, Shengjian, Zhang, Guangtian
• Format: Article
• Language: English
• Subjects: Basic properties; Cementitious materials; Microscopic characteristics; Multi-component; Refractory
• ISSN: 0950-0618; 1879-0526
• DOI: 10.1016/j.conbuildmat.2023.132033

[Display omitted] •The prepared cementitious material can maintain strength, no failure and no obvious deformation under higher temperature treatment (1300℃).•The main components of raw materials are industrial solid waste (fly ash, lime, iron tailing powder), which can realize resource utilization and reduce production costs.•The effects of high temperature mechanics and microstructure of iron tailings powder, fly ash, metakaolin and other materials were systematically explored.•The synergistic effect of iron tailings powder/metakaolin/fly ash can significantly reduce mass loss and strength loss at high temperatures.•Optimized the composition and ratio of multi-component cementitious materials. In order to improve the high-temperature resistance of cementitious materials and further improve their high-temperature resistance theory, this thesis studies a new type of refractory cementitious material. Through systematic research, the material composition of multi-component cementitious materials was optimized. The changes of basic properties such as mass loss, water absorption and strength of composites after high-temperature treatment at 300 °C, 550 °C, 850 °C, 1200 °C and 1300 °C were studied, and the microscopic characteristics such as phase composition, apparent morphology and thermal stability of the composites were analyzed by XRD, SEM and TG-DSC test methods. The results showed that the synergistic effect of iron tailings powder/fly ash/metakaolin (ITP/FA/MK) could significantly improve the residual strength of the material after high-temperature treatment at 1200–1300 °C. On the basis of FA, 11% MK was added to reduce the quality loss after high-temperature treatment. Based on the M0 test block, 10.7%∼32.2% ITP can significantly reduce the quality loss of materials after high-temperature treatment. The XRD results showed that the material phase contained sanidine and mullite before the high-temperature treatment at 850 °C. After the high-temperature treatment at 1200–1300 °C, there was anorthite and gehlenite in the material phase, which was the key to maintaining the strength of the material. The SEM results showed that many hydration products were attached to the surface of FA beads in the sample slurry mixed with MK, FA and ITP at room temperature, making the combination of FA beads and hydration products closer. After the material is treated at a high temperature, the “skeleton” of the material becomes denser. The research on this topic plays a g