The durability of alkali‐activated silico–manganese fume (SMF)‐based mortar specimens was investigated by immersing them in 5% Na₂SO₄ solution and water (controlled environment) for up to 40 weeks. The effect of blast furnace slag (BFS) content [R = BFS/(BFS + SMF) = 0 and 0.3] and alkali concentration (4 and 10 M NaOH_aq) was studied. Visual appearance, variation in alkalinity, mass loss, compressive strength, and microstructural changes were recorded. The maximum strength of 49.4 MPa was noted in BFS‐blended high‐alkaline binder system while the ultimate residual strength and mass loss were 88.8% and − 2.4%, respectively. The high sulfate‐resistance of this binder is attributed to the dense matrix resulting from the formation of C─S─H, K─A─S─H, and C─Mn─H. BFS‐blended mild‐alkaline system exhibited incomplete precursor dissolution thereby gaining a moderate strength of 39.6 MPa with the residual strength and mass loss of 74.1%and − 4.4%, respectively. The decomposition of the specimens on exposure to Na₂SO₄ may be ascribed to high pH differential from the mobility of Na⁺, SO₄²⁻, and OH⁻ in and out of the mortar leading to formation of additional gypsum and calcite. The BFS‐free system displayed excellent stability under sulfate environment owing to the dearth of Ca in SMF. This was notably aided by increased precipitation of quartz together with the formation of degradation products and despite that still attained low strength of about 20 MPa. It is postulated that Ca/Si, Ca/Mn, Si/Mn, Ca/K, and Si/K ratios are the controlling factors influencing the sulfate‐resistance of the developed binders.

中文翻译：

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碱/矿渣活化的硅锰烟气基复合材料的耐硫酸钠性能

碱活化的芯片上的耐久性-锰灰（SMF）基砂浆试件是通过在5％的Na浸渍他们研究₂ SO ₄溶液和水（受控环境）多达40周。高炉矿渣（BFS）含量[R = BFS /（BFS + SMF）= 0和0.3]和碱浓度（4和10 M NaOH_{水溶液）的影响}）进行了研究。记录外观，碱度变化，质量损失，抗压强度和微观结构变化。在BFS混合的高碱性粘结剂体系中，最大强度为49.4 MPa，而最终残余强度和质量损失分别为88.8％和− 2.4％。该粘合剂的高抗硫酸盐性归因于C–S–H，KA–A–S–H和C–Mn–H形成的致密基体。BFS混合的弱碱性系统表现出不完全的前体溶解，因此获得了39.6 MPa的中等强度，残余强度和质量损失分别为74.1％和− 4.4％。样品在暴露于Na ₂ SO _4时的分解可能归因于Na ⁺迁移率高的pH差异。，SO ₄ ^2-和OH ^-和流出砂浆导致形成额外石膏和方解石的。由于不含SFS的Ca，因此在硫酸盐环境下，不含BFS的系统表现出出色的稳定性。显着地，这是由于增加了石英的沉淀以及降解产物的形成而获得的，尽管它仍然达到了约20 MPa的低强度。据推测，Ca / Si，Ca / Mn，Si / Mn，Ca / K和Si / K之比是影响已开发粘合剂耐硫酸盐性的控制因素。