基于Al_(2)O_(3)-SiC浇注料的侵蚀机理谈炉缸结构的选择

Discussion on the Hearth Structure From the Erosion Mechanism of Al_(2)O_(3)-SiC castables

对使用2年的炉缸Al_(2)O_(3)-SiC浇注料进行取样分析,阐明了薄壁炭砖加Al_(2)O_(3)-SiC整体浇注陶瓷杯炉缸的侵蚀机理,并探讨了炉缸结构的选择。其侵蚀机理是,气态K在浇注料中扩散生成带有裂纹的白榴石,为铁水和熔渣渗透提供了通道,并形成钙长石相和铁相,不会形成类似于炭砖侵蚀的脆化层,也不会出现局部炭砖过度溶解的“象脚侵蚀”。认为,薄壁炭砖加Al_(2)O_(3)-SiC整体浇注陶瓷杯炉缸结构,可以在新设计的高炉中采用。

By sampling and analyzing the Al_(2)O_(3)-SiC castables which have been used for 2 years on the BF hearths,it is expounded in the paper the erosion mechanism of the hearth lining constituted by thin-walled carbon bricks and integrally cast Al_(2)O_(3)-SiC ceramic cup,and the selection of the hearth structure is discussed.The erosion mechanism is that gaseous K diffuses in the castable,and generate leucite with cracks,which provides a penetration channel for hot metal and slag,and the possibility of forming anorthite phase and iron phases.Diffusion of gaseous K in the castable will not cause the generation the embrittlement layer which is similar to carbon brick erosion,nor"elephant foot-like erosion"due to excessive dissolution of local carbon bricks.It is considered that the structure of hearth lining constituted by thin-walled carbon bricks and integrally cast Al_(2)O_(3)-SiC ceramic cup can be used in the new blast furnace.