【摘要】 在以高纯红柱石和活性Al2O3细粉为主要原料的试样中,分别加入0、3%、6%、9%和12%的SiC细粉(粒度<0.088mm),试样经1600℃3h烧成后,用XRD、SEM等方法分析试样的相组成和显微结构,并检测试样的体积密度、显气孔率、抗折强度、烧成线膨胀率、抗热震性及蠕变率等,研究了添加SiC细粉对高纯度红柱石基材料的矿物组成、显微结构、烧结状况以及抗热震性与抗蠕变性的影响。结果表明:适量SiC细粉的加入能提高材料中的莫来石含量,促进基质中莫来石晶体的生长,改善材料的组织结构并促进材料的烧结,改善其抗热震性和抗蠕变性;SiC细粉在高纯红柱石基材料中的加入量以6%~9%为宜。更多还原

【Abstract】 SiC fine powder (<0.088 mm) was added in andalusite based refractory specimens,which were mainly composed of high-purity South Africa andalusite with three particle sizes (4~1 mm,1~0 mm and<0.088 mm) and active alumina fine powder (<0.044 mm),and the coarsest (4~1 mm) andalusite aggregate was calcined in advance at 1500 ℃ for 3 h.After the specimens were fired at 1600 ℃ for 3 h and cooled with the furnace to room temperature,their phase compositions and microstructure were examined by means of XRD and SEM,and their bulk density,apparent porosity,firing linear change ratio,creep ratio,bending strength and residual strength ratio after thermal shock were also measured,thereby the effects of SiC fine powder additive on the phase composition,microstructure,sintering state,thermal shock resistance and creep resistance of the high-purity andalusite based refractories were investigated.The results show that the addition of appropriate amount of SiC fine powder can increase the content of mullite phase in the refractories,promote the growth of mullite crystals in the matrix region of the refractories and improve its microstructure.Besides,the addition of appropriate amount of SiC fine powder can also promote the sintering of the high-purity andalusite based refractories and improve the thermal shock resistance as well as creep resistance.It is feasible that 6%~9% SiC fine powder is added in the high-purity andalusite based refractories.更多还原