Microstructures and properties of microporous mullite‐corundum aggregates for lightweight refractories

• DOI: 10.1111/ijac.14123
• Publication Date: 2022-07-25T11:39:04Z
• Authors: Shihua Wang; Wen Yan; Junjie Yan; Stefan Schafföner; Zhe Chen; Shaobai Sang
• Keywords: Mullite; Pseudomorph; Corundum; Particle (ecology)

Abstract Five microporous mullite‐corundum refractory aggregates were prepared from Al(OH) 3 and kaolinite gangue through in situ decomposition synthesis technique. The effects of the sintering temperature (1400–1600°C) particle sizes raw materials (20.6–94.5 μm) on microstructures strengths investigated X‐ray diffractometer, scanning electron microscopy, energy‐dispersive spectrometer etc., to find out technological conditions be controlled industrial production. higher promoted reaction between gangue, leading development primary‐mullite as well generation secondary‐mullite, which formation neck improved strength. Meanwhile, dense mullite layers formed continuously surface pseudomorphs, making micropores inside pseudomorphs become closed pores, increased porosity aggregates. reduction changed packing behavior, accelerated rearrangement pseudomorph particles during process reactive sintering, then reduced porosity. To realize production aggregate with high strength (103 MPa) (16.1%), should at about 1600°C, median diameter 94.5 μm.