Study On The Preparation And Properties Of Alkali Activated Slag Inorganic Coating

Mineral powder is the industrial by-product of iron and steel industry and has hydraulic activity in the action of basic activator or sulfate activator environment.Compared with ordinary portland cement,alkali activated slag has simple production process,faster setting time,better strength and durability,thus attractions from scholars being attracted at home and abroad.With the increase of people's awareness of environment and health,inorganic coatings have been gradually adopted and used in the field of coatings due to their environmental protection,extensive resources and non-toxic advantages.According to the characteristics of low iron content,white color,high strength of activated products,good impermeability and durability of mineral powder,we used alkali activated slag as the base material,mixed with appropriate fillers and film-forming aids to prepare alkali slag inorganic coatings in this paper.By adjusting different water cement ratio,alkali content,water glass modulus,filler content and filler types,the rheological properties,adhesive strength properties and basic properties(surface dry time,surface state,water resistance alkali resistance,temperature resistance and artificial aging resistance)were systematically studied,the conclusions are as follows:1.The rheological behavior of the new alkali slag coating basically conforms to Bingham's rheological model.The influence of water cement ratio on the rheological properties of alkali slag coating is great,but the influences of alkali equivalent,modulus of water glass and the amount of filler on the rheological properties are not very significant;the type of filler has the greatest influence on the rheological properties of alkali slag coating.The rheological properties of TS group is the best,whose yield stress,plastic viscosity and thixotropy are 2.06Pa,0.65Pa·s and213.95Pa·s^-1,respectively.2.The bond strength of different components of alkali activated slag coating and cement mortar matrix increases with the increase of age.With the increase of water cement ratio,the bond strength of each age decreases.With the increase of alkali equivalent,water glass modulus and fillers content,the bond strengths of each age increase first and then decrease.The bond strength of the composite system is higher than that of the single system,and the maximum bond strength of the composite system(TS group)is 1.76Mpa in 28d.3.The hydration mechanism of alkali activated slag coating and the bonding mechanism of interface with cement mortar are discussed in this paper.In alkali activated slag coating,the C-S-H gel is generated by the alkali activated slag after the depolymerization of the slag,then reacting on the base side of the cement mortar to rivet the coating with the substrate,so that the connection structure between the coating and the cement base body is more dense.4.The surface drying times of different components of alkali activated slag coating are?2h.The surface states of the alkali activated slag coating are related to the rheological properties and the early hydration rate of the slurry,the water resistance,alkali resistance and temperature resistance of the alkali activated slag coating meet the standards,and the aging resistance is related to the density of the hydration products of the alkali activated slag coating.