硫、氯氧镁混合胶凝体系凝结硬化性能及微观结构

发布时间：2018-03-08 09:06

本文选题：硫氧镁水泥　切入点：氯氧镁水泥　出处：《硅酸盐通报》2017年08期 　论文类型：期刊论文

【摘要】：为了改善镁质胶凝材料的性能,结合硫氧镁水泥和氯氧镁水泥两个体系的特性,制备了硫、氯氧镁混合胶凝体系。通过测试凝结时间、抗压和抗折强度对混合体系的凝结硬化性能及耐水性进行了研究,利用XRD、SEM和EDS分析表征手段对混合体系水化产物的物相组成、元素分布及微观形貌进行了分析。结果表明:溶液中氯化镁质量分数增加,浆体的凝结时间延长,当氯化镁质量分数大于70%,凝结时间缩短。与硫氧镁水泥和氯氧镁水泥相比,混合体系的抗压强度降低、抗折强度稍有增加,浸泡28 d后表现出了良好的耐水性。XRD和SEM数据表明:晶体之间没有形成连结力强的连续结构,使混合体系的力学性能降低。浸水后水化产物微观形貌的改变是混合体系耐水性增加的主要原因。
[Abstract]:In order to improve the properties of magnesia cementitious materials, a mixture of sulfur and magnesium oxychloride was prepared by combining the properties of magnesium oxysulfide cement and magnesium oxychloride cement. The condensation hardening properties and water resistance of mixed systems were studied by compressive and flexural strength. The phase composition of hydration products of mixed systems was characterized by XRD-SEM and EDS. The results show that when the mass fraction of magnesium chloride in the solution is increased, the setting time of the slurry is prolonged. When the mass fraction of magnesium chloride is greater than 70, the setting time is shortened, which is compared with that of magnesium sulfate cement and magnesium oxychloride cement. The compressive strength of the mixed system decreased and the flexural strength increased slightly. After immersion for 28 days, good water resistance. XRD and SEM data showed that there was no continuous structure with strong bonding force between the crystals. The mechanical properties of the mixed system were decreased, and the change of the micromorphology of hydration product after immersion was the main reason for the increase of the water resistance of the mixed system.
【作者单位】：中国科学院青海盐湖研究所;青海省盐湖资源化学重点实验室;中国科学院大学;
【分类号】：TQ177.5

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