- •Introduction
- •Viscosity silicate fusion.
- •Viscosity
- •Однокомпонентные системы.
- •Правило определения путей кристаллизации двухкомпонентных систем с ликвацией и полиморфными превращениями.
- •Правило определения пути кристаллизации двухкомпонентной системы с образованием твердых растворов.
- •Диаграмма состояния двухкомпонентных систем с образованием твердых растворов
- •Применение правила рычага в двухкомпонентных системах.
- •Треугольник концентраций
- •2.Точки составов химических соединений.
- •3.Пограничные кривые и поля первичной кристаллизации.
- •1 . Triangle of concentration
- •2. Point of structures of chemical connections.
- •In temperature began crystallization of allou (or end melting of a firm mix) there will be a temperature appropriate by that isoterm, on which the point of structure it allou gets.
- •The definition of structure primary crystallized from melt of a firm phase
- •Definition of final phases and final point of crystallization on the diagrams of a condition
- •Definition of a primary way of change of structure liquid phase after beginning of crystallization
- •Definition of way of crystallization at polymorphic transformations
- •The definition of structure primary crystallized from melt of a firm phase
- •Definition of final phases and final point of crystallization on the diagrams of a condition
- •Definition of a primary way of change of structure liquid phase after beginning of crystallization
- •Definition of way of crystallization at polymorphic transformations
- •Definition of a primary way of change of structure liquid phase after beginning of crystallization
- •Definition of way of crystallization at polymorphic transformations
- •Тема: Применеие правила рычага в трехкомпонентной системе. Системы MgO-Al2o3- SiO2, k2o - Al2o3- SiO2, Na2o - CaO- SiO2, Li2o - Al2o3- SiO2
- •System Na2o—CaO—SiO2
- •System CaO-ai2o3-SiO2
- •System MgO—а12о3—SiO2
Definition of final phases and final point of crystallization on the diagrams of a condition
At the given structure initial melt the diagram of a condition allows even without construction of a way of crystallization to define structure of final crystal phases after end of crystallization of melt. On final phases it is possible to define on the diagram a final point of crystallization, which characterizes temperature, at which comes to an end of crystallization and structure of a liquid phase at last moment of crystallization. At job with the diagrams of a condition it is recommended to do it before construction of a way of crystallization, that allows limiting this way initial and final points and by that to avoid mistakes at definition of a sequence of phase changes. The structure of final crystal phases after end of crystallization three-component of melt is defined by a rule of an elementary triangle.
Final products of crystallization are those three connections, the points of which structures lay in tops of an elementary triangle, inside which there is a point of structure initial melt. A final point of crystallization three-component melt is that threefold point, in which the fields of primary crystallization of final phases of crystallization converge.
For example, the diagram of three-component system with binary connection АС, melting incongruous (fig. 2), contains two elementary triangles A-B-AC and АС-В-С. For all three-component melts, the points of which structures get in an elementary triangle A-B-AC, final phases of crystallization according to the stated rule will be connections A, B and АС, forming this elementary triangle, and final point of crystallization - point of double lowering G, in which the fields of primary crystallization of these connections converge. Precisely as all melts, the points of which structures get in an elementary triangle АС-В-С, finish to crystallize in eutectic Е with allocation of connections АС, B and C as final phases of crystallization.
Figure 2- The diagrams of a condition of three-component system with double (binary) chemical connection AC incongruous melting
It is necessary to specify, that at job with the diagrams of a condition there can be so-called special cases, at which some general rules are not always applicable. It, for example, concerns to definition of final phases of crystallization, when the point of initial melt gets on a connecting straight line or precisely corresponds to a point of structure any of connection in the given system. If the point of initial structure gets on a connecting straight line (for example, a point a, fig. 2), final phases of crystallization will be those two connections (B and АС), the points of which structures are connected by this connecting straight line (in similar cases initial structure it is necessary to consider as belonging private to two-component system formed by these connections). If the point of structure of initial melt precisely corresponds to structure of any connection, a final product of crystallization will be one phase - crystals of this connection.