Thermodynamic computations and analysis of the phase diagrams of multicomponent systems

№ 2725    МИНИСТЕРСТВО ОБРАЗОВАНИЯ И НАУКИ РФ
ФЕДЕРАЛЬНОЕ ГОСУДАРСТВЕННОЕ АВТОНОМНОЕ ОБРАЗОВАТЕЛЬНОЕ УЧРЕЖДЕНИЕ ВЫСШЕГО ПРОФЕССИОНАЛЬНОГО ОБРАЗОВАНИЯ
   «НАЦИОНАЛЬНЫЙ ИССЛЕДОВАТЕЛЬСКИЙ ТЕХНОЛОГИЧЕСКИЙ УНИВЕРСИТЕТ «МИСиС»

  Кафедра металловедения цветных металлов




                А.В. Поздняков
                В.В. Чеверикин
                О.А. Яковцева




  THERMODYNAMIC
  COMPUTATIONS AND ANALYSIS
  OF THE PHASE DIAGRAMS
  OF MULTICOMPONENT SYSTEMS





  Учебное пособие



   Рекомендовано редакционно-издательским советом университета


Москва 2015

УДК 536.717 П47


Рецензент канд. техн. наук А.Н. Алабин




            Поздняков А.В.


П47 Thermodynamic computations and analysis of the phase diagrams of multicomponent systems : учеб. пособие / А.В. Поздняков, В.В. Чеверикин, О.А. Яковцева. - М. : Изд. Дом МИСиС, 2015. -37с.- Текст англ.
          ISBN 978-5-87623-935-8

          В пособии представлены возможности программы Thermo-Calc, которая позволяет проводить термодинамические расчеты двойных, тройных и многокомпонентных фазовых диаграмм, фазового состава сплавов, состава фаз, неравновесной кристаллизации. Показано применение программы для расчета фазового состава промышленных сплавов, а также даны рекомендации по выполнению курсовой работы.
          Содержание пособия соответствует программе дисциплины «Thermodynamic computations and analysis of the phase diagrams of multicomponent systems» для студентов, обучающихся по магистерской программе «Advanced Metallic Materials and Engineering».

УДК 536.717

          This tutorial presents the program features Thermo-Calc, which allows to carry out thermodynamic calculations of binary, ternary and multicomponent phase diagrams, phase composition of the alloys, composition of the phases, the non-equilibrium crystallization, the application program to calculate the phase composition of industrial alloys and recommendations for implementation of course work.
          The content of the tutorial corresponds to the program of discipline “Thermodynamic computations and analysis of the phase diagrams of multicomponent systems”, for students studying on master’s program “Advanced Metallic Materials and Engineering”.

© А.В. Поздняков,
                                                      В.В. Чеверикин,
                                                      О.А. Яковцева, 2015
ISBN 978-5-87623-935-8                             © НИТУ «МИСиС», 2015

CONTENT


Introduction                                                       4
1  Calculations of binary and ternary phase diagrams                7
2  Calculation of polythermal sections                            12
3  Calculation of isothermal sections                             17
4  Calculation of phase composition and composition of the phases 20
5  Calculation of non-equilibrium crystallization                 22
6  Application of Thermo-Calc to calculate phase composition
of industrial alloys                                              26
7  Recommendations for implementation of course work              33
References                                                        36

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                Introduction




      To provide the required mechanical and technological properties of alloys need to choose their composition. In this case it is useful to use the phase diagram of systems. Using phase diagrams allow for analysis of the phase composition, structure and properties of materials in specific operating conditions. Currently, binary and ternary the phase diagram of metallic systems have been well studied. But only knowledge of binary and ternary phase diagrams is not enough for a complete representation of the phase composition of industrial alloys that can contain up to ten or more elements. Respectively, it is necessary to investigation of the multicomponent phase diagrams and for their investigations we can use the Thermo-Calc software.
      Thermo-Calc software is a software package that contains a large number of thermodynamic data for calculations of phase diagrams. Calculations based on thermodynamic databases, an assessment of the experimental data using the CALPHAD method.
      CALPHAD (CALculation of PHAse Diagrams) - method of calculation of phase diagram.
      Under the equilibrium phase diagram usually understand diagrams depending on the composition of the chemical system of the temperature. The phase diagram of the areas of existence are marked compounds and solutions (i.e. phases) and the area of their coexistence.
      Phase diagrams - a very powerful tool to predict the state of the system under different conditions. They first appeared as a graphic method of generalization of experimental data on the equilibrium.
      In the CALPHAD method one collects and assesses all available experimental and theoretical information available on phase equilibria and thermochemical properties in a system. Thus it is possible to calculate the phase diagram by an initial assessment of the thermodynamic properties of all phases of the system.
      CALPHAD method brings together all experimental information on the phase equilibria in the system and all the thermodynamic information obtained during the thermochemical and thermophysical investigations. Further set of thermodynamic properties of each phase is described by a mathematical model containing adjustable parameters. These parameters are evaluated by optimizing the fit of the model to all the assessed information, also involving coexisting phases. Following this it is possible to recalculate the phase diagram, as well as the thermodynamic

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