Hybrid Cements From Metakaolin, Slag And Clinker Mixtures. Influence Of Activators

Abstract

Hybrid cements containing a mixture of aluminates gels-substituted CSH (CASH) and NASH phases and other phases are investigated. The mechanical strength and structures of hybrid cement with geopolymeric matrix of aluminosilicates and clinker are examined. These geopolymeric matrixes are based on polycondensation of the powder precursors by alkaline activation. The activators can be solids (alkalis of sulfates and carbonates,) or liquid (alkaline solutions of silicates). The type of alkaline cation (Na, K) influences the activation. The phase’s transformations are characterised by the following parameters: the effect of cures (2, 7, 28 days) and their impact on the hardening, the texture and the mechanical strength. These properties are correlated by complementary techniques of DRX, FTIR, SEM / EDX. Alkaline potassium K more than the sodium Na allows the obtaining of products of denser reactions what increases the strength of cohesion of the matrix and show higher mechanical resistances.