高炉用SiC砖显微结构及其抗侵蚀特征

用显微分析手段对高炉用四种Ｓｉ３Ｎ４结合及Ｓｉａｌｏｎ结合的ＳｉＣ砖进行了分析观测,测定了四种样品的抗氧化,抗碱侵及抗渣侵的能力。发现ＳｉＣ耐火材料的抗侵蚀能力与其显微结构密切相关,结构越致密,ＳｉＣ砖的抗侵蚀能力越强,ＳｉＣ砖中胶结相的胶结力是其结构性能的关键,Ｓｉ３Ｎ４及Ｓｉａｌｏｎ的网状结构愈发育,砖体的抗侵蚀越强,测定分析了四种样品的碱侵蚀产物,发现“过剩氧”的存在是砖体碱侵破损的原因之一

Microstructure and Anticorrosion Behavior of SiC Bricks for Blast Furnace

Four kinds of SiC bricks bonded with St3C4 and Sialon were analysed microscopically to determine their resistances to oxidation,alkali attack and slag attack. It was found that the resistance to corrosion of SiC refractories relates closely to their microstructures. The more the compactness of a SiC b.ick is,the higher resistance to corrosion will be. In this respect,the bondability of the bonds used in brick is crucial.The more the network structures of Si3N4 and Sialon developed,the higher the resistance to corrosion will be in a brick. After the products due to alkali attack were analysed,it was revealed that one of the reasons why bricks fail due to alkali attack is the presence of " extra oxygen".