This paper investigates the behavior of calcined powder made of natural magnesite and natural steatite. The magnesite and steatite are made into a powder of ratio 3 : 1 by weight proportion, and the combination is thermally decomposed at a temperature of 1200° Celsius. The calcined powder along with and without Sodium Tripolyphosphate (STPP) salt is tested for its microscopic structural development, consistency, initial setting time, final setting time, and heat of hydration. The powder is made into paste with water/powder ratio as 0.25 and the hardened samples are tested for its compressive strength, drying shrinkage, pH value, SEM analysis, and XRD analysis. The results show that adding phosphate salt increases the hydration process, setting time, and strength aspects. The test samples are found with hydration products such as magnesium hydroxide and struvite. Thus, the present work shows that natural metamorphic magnesite and natural metamorphic steatite can be the potential alternative resource for the production of magnesium-based binder.

中文翻译：

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煅烧镁基矿物粉及其替代粘结剂性能的研究

本文研究了天然菱镁矿和天然滑石制成的煅烧粉末的行为。将菱镁矿和滑石制成重量比为3：1的粉末，并将该组合在1200摄氏度的温度下热分解。测试煅烧后的粉末以及是否添加三聚磷酸钠（STPP）盐的微观结构，稠度，初始凝固时间，最终凝固时间和水合热。将粉末制成水/粉末比为0.25的糊剂，并测试硬化样品的抗压强度，干燥收缩率，pH值，SEM分析和XRD分析。结果表明，添加磷酸盐会增加水合过程，凝结时间和强度方面。发现测试样品中含有水合产物，例如氢氧化镁和鸟粪石。因此，目前的工作表明，天然变质菱镁矿和天然变质滑石可以成为生产镁基粘结剂的潜在替代资源。