重力分离SHS法制备陶瓷内衬复合钢管耐蚀性的研究

Corrosion Resistance of Ceramic Lined Pipes Prepared by Gravitational Separation SHS Process

基于重力分离ＳＨＳ法制备了陶瓷内衬复合钢管，分析了内衬陶瓷层的组织结构及添加剂ＳｉＯ２和ＣｒＯ３对复合钢管耐蚀性的影响。研究发现，内衬陶瓷层主要由构成枝晶的α－Ａｌ２Ｏ３基体相和分布于其间的ＦｅＯ·Ａｌ２Ｏ３尖晶石相所组成，ＳｉＯ２主要以石英相结构存在于枝晶晶界中。在Ｆｅ２Ｏ３＋Ａｌ＋ＳｉＯ２体系中，陶瓷层的腐蚀主要为晶间腐蚀，并在ＳｉＯ２添加量为４％ｗｔ时，复合钢管的腐蚀失重率出现极大值（约为１．８６２２ｇ／·ｍ２·ｈ－１）；在Ｆｅ２Ｏ３＋Ａｌ＋ＣｒＯ３体系中，陶瓷层的腐蚀主要为缝隙腐蚀，复合钢管的腐蚀失重率随ＣｒＯ３添加量增加而增多。

Abstract The structure of ceramic lining of steel pipes and the effect of additives SiO\-2 and CrO\-3 on corrosion resistance of the pipes have been investigated. It was found that the ceramic lining was composed of Al\-2O\-3 phase assuming dendrihic crystals and FeO\5Al\-2O\-3 spinel phase,and SiO\-2 distributed at dendritic boundary zone.Corrosion process in Fe\-2O\-3AlSiO\-2 system was mainly controlled by intercrystalline attack,whereas in Fe\-2O\-3AlCrO\-3 system by crevice attack. The weight loss rate (g\5m\+\{-2\}\5h\+\{-1\})would increase with increasing addition of CrO\-3 in thermit mixtures.