Shabanova G. Physical and chemical principles of special cements creation in system BaO-Al2O3-Fe2O3-SiO2

The object of research - subsystems of the quaternary system BaO-Al2O3-Fe2O3-SiO2, compounds and heterogeneous compositions of phases which are a basis of special barium-containing cements of a new class; the aim of investigation is creation of scientific bases for prognostication of existence of phases and determination of laws of their formation in the system BaO-Al2O3-Fe2O3-SiO2, an experimental substantiation of features of its subsolidus composition, optimization of technological parameters for the synthesis of of new kind of special cements with given phase composition, physical and chemical properties and service characteristics and concretes on their basis; methods - advanced techniques for investigation of multicomponent systems, a complex of methods of physical and chemical analysis; theoretical and practical results - the thermodinamic data base of barium-containing compounds is made; the subsolidus composition of ternary systems BaO-Al2O3-SiO2, BaO-Al2O3-Fe2O3 and BaO-Fe2O3-SiO2 is reconsidered; in the first time the study of quaternary system BaO-Al2O3-Fe2O3-SiO2 is carried out and it is determined that at the temperature 1108 oC in the system a reorganization of the connods proseeds, that results in change of the subsolidus structure of the concentration tetrahedron of the main system, the topological graph of interrelation of the elementary tetrahedrons has been constructed and their geometrical and topological characteristics has been given; resourse- and energy-saving technology for the barium-containing cements production is developed; novelty - physical and chemical bases for the obtaining of a new class of special barium-containing cements, which based on fundamental principles of thermodynamics in relation to phase relation in thesobsolidus area of the multicomponent system BaO-Al2O3-Fe2O3-SiO2 and base principles of synthesis of barium-containing cements with the complex of the service characteristicsand conretes in terms of one are grounded, the principles of obtaining and regulation of phase composition of barium-containing cements have been determined theoretically; these cements are synthesized under conditions of fast and slow cooling which deremined by possibilities of convertibility of the thermodynamic relation in solid-state phase reactions of quaternary system; it is proved that calculation composition of barium-containing clinkers corrresponds sufficient to the quantitative and qualitative phase corelation in the real clinkers; this fact allows to obtain special barium-containing cements of given phase composition by means of purposeful synthesis; kinetic laws of phase-formation processes of barium-containing cements are ascertained and features of their hardening mechanism and hydration processes are revealed; а subject and degree of introduction - constructive elements of protection from ionizing radiation of the laboratory accelerator of the electrons and gamma-quantums; effectiveness of introduction - 500 000 uah in year; field of use - protective containers, constructions and buildings of nuclear power energetics, constructional elements of magnesian electrolyzer, oil-well mortar for gas and oil boreholes.