骨料特性对刚玉-莫来石浇注料性能的影响

Effect of Aggregate Characteristics on Properties of Corundum-Mullite Castables

刚玉-莫来石浇注料主要用于各类窑炉内衬材料的制备,为进一步提高内衬材料的使用性能,采用杂质含量不同的预合成莫来石和红柱石,研究了骨料种类和杂质含量对刚玉-莫来石浇注料显微结构与力学性能的影响。结果表明,当热处理温度为1100℃和1550℃时,莫来石骨料的杂质元素扩散进入基质中,降低了基质中液相的生成温度,促进了浇注料的烧结,因此添加莫来石骨料的浇注料比添加红柱石骨料的浇注料力学性能更加优异;杂质含量高的MS60骨料在高温下形成的液相较多,能够有效促进浇注料的烧结,提升浇注料的常温力学性能,其在1550℃时的抗折强度和抗压强度分别为10.7 MPa和115.2 MPa。但高温抗折强度会因液相较多而降低,其值为0.7 MPa;杂质含量高的红柱石骨料D59的莫来石化程度大,产生的富硅玻璃相黏度低,可以促进浇注料的烧结和二次莫来石生成,从而改善浇注料的力学性能,D59浇注料的高温抗折强度为0.7 MPa。

Corundum-mullite castable castable is mainly used to prepare various kilm lining materious,in order to further improve the performance of lining materials,mullite and andalusite were pre-synthesized with different impurity contents to study the effects of aggregate type and impurity content on the microstructure and mechanical properties of corundum-mullite castable.The results showed that when the heat treatment temperature was 1100℃and 1550℃,the impurity elements of mullite aggregate diffused into the matrix,reduced the formation temperature of liquid phase in the matrix,promoted the sintering of castable,so that the castable with mullite aggregate was better than the castable with andalusite.The MS60 aggregate with high impurity content formed more liquid phase at high temperature,which could effectively promote the sintering of castable and improve the mechanical properties of castable at normal temperature,the flexural strength and compressive strength were 10.7 MPa and 115.2 MPa at 1550℃,respectively.But the high temperature bending strength will be reduced to 0.7 MPa due to more liquid phase.The andalusite aggregate D59 with high impurity content had a large degree of mullite,and the viscosity of silica-rich glass phase generated is low,which promoted the sintering of castable and the generation of secondary mullite,improved the mechanical properties of castable,and its high temperature flexural strength reached 0.7 MPa.