The aim of this work was to study the mechanical strength and microstructure changes of alkali-activated slag mortar (AAS mortar) after being heat treated in the temperature range of 200−1000 °C. The AAS mortar was cured in the ambient condition (20 ± 5 °C, 60 ± 5% RH) (Relative humidity: RH) and high temperature condition (80 °C) for 27 days with three different heating regimes: curing in a dry oven, curing in sealed plastic bags, and in a steam environment. The activator for the AAS synthesis was a mixture of sodium silicate solution (water glass) and sodium hydroxide (NaOH) with a SiO2/Na2O weight ratio of 1, and a dosage of 4% Na2O by slag weight. Thermogravimetric analysis (TGA) and scanning electron microscopy (SEM) incorporated with energy-dispersive X-ray spectroscopy (EDX) were used to assess the mortar microstructure change. The results revealed that the curing method significantly affected the mechanical strength of AAS at temperatures lower than 800 °C. The heat treatment at late age of 28 days was more beneficial for compressive strength enhancement in specimens without using heat curing methods.
展开▼
机译：这项工作的目的是研究在200-1000℃的温度范围内热处理后碱活性炉渣（AAS砂浆）的机械强度和微观结构变化。用三种不同的加热制度将AAS砂浆固化（相对湿度：RH）和高温条件（80°C）和高温条件（80°C）：固化干燥烤箱，在密封塑料袋中固化，并在蒸汽环境中。用于AAS合成的活化剂是硅酸钠溶液（水玻璃）和氢氧化钠（NaOH）的混合物，SiO 2 / Na 2O重比为1，用渣重量为4％Na 2 O的剂量。使用热量分析（TGA）和扫描电子显微镜（SEM）与能量分散X射线光谱（EDX）一起用于评估砂浆微观结构的变化。结果表明，固化方法在低于800℃的温度下显着影响AA的机械强度。在28天晚期的热处理在不使用热固化方法的情况下对样本的压缩强度提高更有益。
展开▼
