The main chemical composition of the micro silica fume is SiO2, content can up to 98%. Its elements include Fe2O3, Al2O3, CaO, K2O, Na2O, MgO, C, etc. The bulk density of raw ash is 150-200 kg/m3. For transportation and construction application, the original ash must be densified. The bulk density after densified can reach 350-700kg/m3.
According to the model, micro silica fume is divided into: 850 U (D), 920 U (D), 940 U (D), 960 U (D), and so on, according to the field of application: ground floor special, concrete engineering special, general refractory and high-grade refractory materials, ceramic products and so on.
As new material, micro silica fume is widely used in the refractory industry. It has an important effect on the improvement of the amorphous refractory. The practical application is in the following aspects:
1. Instead of pure aluminum oxide as refractories.
2. The production of amorphous and shaped refractory products as additives, makes the strength and high temperature performance greatly improved.
3, the overall casting ladle with coagulant.
4, other cohesive agents, binders, coagulants and additives for other refractory products.
Low price silica fume function for refractory:
1. Improve the fluidity of the amorphous refractory castable, reduce the water consumption, make it easy to form, and increase the production efficiency.
2. The compactness and strength of the refractories are greatly improved by the micro silica fume, due to the filling of the ultramicrostructure.
3, silica fume has high activity. Under the premise of the existence of Al2O3 components, it is easier to generate mullite phase, so that the high temperature strength and thermal shock resistance of refractories are significantly improved.