Wang Xiaoyu, Wang Saixin, Mu Yuandong, Zhao Ruijie, Wang Qingfeng, Parr Chris, Ye Guotian
Henan Key Laboratory of High Temperature Functional Ceramics, School of Materials Science and Engineering, Zhengzhou University, Zhengzhou 450001, China.
Gongyi Shunxiang Refractories Co., Ltd., Zhengzhou 450001, China.
Materials (Basel). 2021 Aug 24;14(17):4775. doi: 10.3390/ma14174775.
Additions of andalusite aggregates (19 wt%) were shown in previous literature to enhance the antioxidation of AlO-SiC-C (ASC) castables. This work aims to investigate whether micronized andalusite has a greater influence on antioxidation improvement than andalusite aggregates. Various low contents (5 wt% and below) of micronized andalusite (≤5 μm) were introduced as a substitute for brown fused alumina in the matrix of ASC castables. The antioxidation of castable specimens was estimated by the oxidized area ratio on the fracture surface after a thermal shock test. The microstructure and phases of micronized andalusite and the castable specimens were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD), respectively. The results suggest that the antioxidation effects of ASC castables with a low addition of micronized andalusite are effectively enhanced. The heat-induced transformation of andalusite produces SiO-rich glass, favoring the sintering of the castable matrix and impeding oxygen diffusion into the castable's interior. Therefore, the castable antioxidation is enhanced without deteriorating the hot modulus of rupture.
先前文献表明，添加红柱石骨料（19重量%）可增强AlO-SiC-C（ASC）浇注料的抗氧化性能。本工作旨在研究微细化红柱石对抗氧化性能改善的影响是否比红柱石骨料更大。引入各种低含量（5重量%及以下）的微细化红柱石（≤5μm），以替代ASC浇注料基体中的棕刚玉。通过热震试验后断口表面的氧化面积比来评估浇注料试样的抗氧化性能。分别采用扫描电子显微镜（SEM）和X射线衍射（XRD）对微细化红柱石和浇注料试样的微观结构及相进行表征。结果表明，低添加量微细化红柱石的ASC浇注料的抗氧化效果得到有效增强。红柱石的热致转变产生富含SiO的玻璃，有利于浇注料基体的烧结，并阻碍氧气扩散到浇注料内部。因此，在不降低热抗折强度的情况下提高了浇注料的抗氧化性能。
