Pure Friedel salt (3CaO · Al2O3 · CaCl2 · 10H2O,main corrosion product of cement-based materials by chloride ions) and ettringite (AFt,3CaO · Al2 O3 · 3CaSO4 · 32H2 O,main corrosion product of cement-based materials by sulfate ions) were chemically synthesized and then characterized via X-ray diffraction and TG-DSC test to investigate their stabilities and transform mechanism.The interaction between different corrosion ions was explored by immersion experiment.The results indicated that sul fates have a significant impact on Friedel salt,as sulfate ions can substitute for chloride ions in Friedel salt and convert Friedel salt into ettringite.Chloride salts can also react with ettringite,leading to ettringite's decomposition.There is an equilibrium between Friedel salt and ettringite,and the inter-transform of them can be achieved under certain conditions.The study verified the interaction effect during the corrosion process of the compound solution of chloride salt and sulfate toward hardened cement paste.%化学合成了氯离子在水泥基材料中的主要侵蚀产物Friedel盐(3CaO·Al2O3·CaCl2·10H2O)以及硫酸根离子在水泥基材料中的主要侵蚀产物钙矾石(3CaO·Al2O3·3CaSO4·32H2O),采用XRD和综合热分析(TG-DSC)研究了二者的稳定性与转变机理,通过浸泡实验探究不同侵蚀性离子之间相互作用对水泥基材料的影响.结果表明:硫酸盐对Friedel盐稳定性影响显著,硫酸根离子置换Friedel盐中的氯离子,并最终生成钙矾石;氯盐对钙矾石的稳定性也有影响,氯盐同样可以使钙矾石分解.两种腐蚀产物之间存在平衡,并且在一定条件下可以相互转化.实验证实氯盐与硫酸盐复合溶液对水泥混凝土侵蚀过程中存在复杂的离子交互作用.
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