Cellular Structure Formation of Composite Materials

Abstract

The article is devoted to magnesia thermal insulation materials. The aim of the work is to study porization and hardening of magnesia composites with a cellular structure. Technogenic fillers were used for synthesis of composite materials. Materials’ cellular structure was formed by foaming. Properties of the foam mass were evaluated by multiplicity, density, and durability. The materials were studied using X-ray phase analysis, electron microscopy, physical and mechanical methods. Properties of foam obtained from solutions of various salts have been investigated. Protein foam concentrates are preferable for obtaining stable, fine-pored foam from magnesium chloride solution. Foam control is achieved by combining magnesium chloride and zinc chloride solutions. It has been determined that hardening of composite materials slows down in the presence of foam concentrates. There has been developed a method to stimulate hardening processes of porous composites. It was found out that mechanical activation of a composite magnesia binder and molding mixture’s separate preparation accelerate hydration and increase porous material’s strength by 60%. It was revealed that strengthening of a cellular structure of composites is achieved by fibrous magnesium hydroxychlorides formation. A resource-saving technology has been developed for effective heat-insulating magnesia materials with a density of less than 500 kg/m³.