Phase transformations

Phase diagrams of binary and multicomponent systems are the basis of modern alloy theory. The ability to use them in solving various practical problems is a necessary part of material scientists training. The skills and knowledge acquired during the course will help you to:
• create new alloys and improving the existing ones;
• modernize metallurgical processes for obtaining metals and compounds and cleaning them from impurities;
• optimize technologies for the production of blanks from these alloys;
• research the coatings, surfacing, castings, etc.
Phase diagrams contain the necessary information about the alloys composition under equilibrium or close to them conditions and about the temperatures of the beginning and end of phase transformations.

The course will acquaint you with the phase transformations that occur in alloys of binary phase diagrams. By the end of the course you:
• will know all types of binary phase diagrams;
• will analyze the transformations of any alloy in equilibrium and non-equilibrium conditions;
• will assess the volume fraction and composition of phases;
• will describe the structure of different alloys;
• will choose heat treatment modes to eliminate the non-equilibrium structure.

You may find some of the themes challenging, but we have included many visual material to help you master this course.

• Introduction
• Welcome to the Phase Transformation course! In this module, you will learn what the Gibbs phase rule is, and we will introduce you to the classifications of binary phase diagrams.
• Phase diagrams with complete solubility in the liquid and solid phase
• Module 2 focuses on phase diagrams with continuous solid solutions. We will examine diagrams with extremum points on the liquidus and solidus curves, as well as phase diagrams with a miscibility gap at low temperatures. We will learn to describe crystallization processes in the temperature interval and determine the volume fraction of phases. In addition, we will discuss liquation and methods to eliminate the liquation structure.
• Diagrams with eutectic and peritectic equilibrium
• Module 3 focuses on phase state diagrams of systems with eutectic and peritectic equilibrium. We will discuss the features of the equilibrium and non-equilibrium crystallization of such systems and learn what a eutectic modification is.
• Phase diagrams with intermediate phases
• Module 4 focuses exclusively on phase diagrams with intermediate phases. We will discuss different types of phase diagrams with intermediate phases crystallizing from the liquid state, and also analyze the phase diagrams with peritectoid transformation and ordering of intermediate phases in the solid state.
• Phase diagrams with polymorphous elements and compounds
• Module 5 focuses on phase diagrams for polymorphic elements. We will learn what eutectoid, monotectoid and metatectic equilibria mean, and also discuss phase diagrams with polymorphic intermediate phases.
• Limited miscibility in liquid stage
• In module 6 we will learn which elements can be limitedly soluble in the liquid state. We will discuss the phase diagrams of elements that crystallize from their own melts, as well as phase diagrams with monotectic and syntectic equilibria.
• Complex binary phase diagrams
• In module 7 we will summarize the material that we have studied in the course.