Abstract:

Nitride bonded silicon carbide bricks after used in a 170 t·h^-1 coke dry quenching oven for 6 years in inclined channel area (up and down) were researched.The changes of chemical composition,bulk density,cold strength,hot strength,pore size distribution,phase makeup and microstructure were discussed.The results show that:(1)both the contents of SiC and Si₃N₄ decrease,while the content of SiO₂ increases substantially (up 291.3% to 722.5%),the pore size enlarges (d₅₀ increases 22%-239%);the CMOR and HMOR for up brick decrease substantially (47.9% and 48.5%,respectively);the CMOR and HMOR for down brick decrease slightly (8.6% and 11.0%,respectively);(2)such change is aroused by the oxidation of nitride bonded silicon carbide.The oxidation for up brick is more serious than that of down brick,and also the oxidation for surface is more serious than inner.

Key words: coke dry quenching technology, coke dry quenching oven, nitride bonded, silicon carbide brick

摘要：

分析了在某170 t·h^-1干熄炉 “牛腿”上部和下部使用6年后的氮化物结合碳化硅砖在化学组成、致密度、常温强度、高温强度、气孔孔径、物相组成、显微结构等方面的变化。结果表明:1)在170 t·h^-1干熄炉使用6年后,上部砖和下部砖的SiC含量和Si₃N₄ 含量均减少,SiO₂含量均大幅度增多(增多291.3%~722.5%),气孔孔径均增大(d₅₀增大22%~239%);上部砖的常温抗折强度和高温抗折强度大幅减小(分别减小47.9%和48.5%),下部砖的常温抗折强度和高温抗折强度小幅减小(分别减小8.6%和11.0%)。2)用后氮化物结合碳化硅砖的上述变化是氧化造成的。上部的氧化比下部的严重,表层的氧化比内部的严重。

关键词: 干熄焦技术, 干熄炉, 氮化物结合, 碳化硅砖