Lecture 25
Phase diagram
Recap
Isomorphous system
Variables in two phase region
Microstructural changes during cooling and heating of a
binary system
Compositional changes in two phase regions
Application of tie line and lever rule
Eutectic diagrams

Lecture 10
Voids in Solids
Recap
Coordinates of Motif in HCP crystal
Ideal c/a ratio in hcp crystal
BCC crystals
Packing fraction
Planar density
Identified octahedral and tetrahedral voids in CCP crystals
Determined the size of largest atom that co

Lecture 27
Iron Carbide Phase
Diagram
Recap
Eutectoid diagram
Peritectic diagram
Peritectoid diagram
Complex diagram
Important phases and reactions in
Fe-Fe3C diagram
Fe-Cementite diagram
Three reactions are seen in the Fe rich side: (i) Peritectic,

Lecture 9
Structure of Solids
Recap
Laue technique: variable, fixed
Spot pattern
Recap
CCP or FCC structure
1)Imp. class of materials that exhibit the
structure
2) Atomic sequence
3) Close packed plane
4) Close packed direction
5) Relationship between ato

Lecture 4
Crystal Geometry
and
Structure Determination
1
Recap
Configuration entropy
Gibbs free energy and its temperature dependence
Stability criteria based on Gibbs free energy
Arrhenius equation
Concept of lattice, motif and unit cell
Crystal = Lattic

Lecture 22
Phase Diagrams
or
Equilibrium diagrams
Recap
Screw dislocations can change its slip plane by cross slip
and double cross slip processes
Estimation of surface energy
Grain boundaries
High angle and low angle boundaries (Tilt boundary and
twist b

Lecture 23
Phase Diagrams
Recap
Important definitions of microstructure,
phase and component
Variables of the system: Thermodynamic
variable and composition variable
Total variables of the system can be
defined as P (C-1)
Equilibrium constraints of the sy

Lecture 20
Crystal
imperfections
Recap
Energy of a dislocation line can be given as
1 2
E Gb
2
Identified Burgers vector of dislocations in cubic
crystals
Dislocation-dislocation interaction
a)
Positive edge dislocation
Negative edge dislocation
ATTRACTIO

PROGRESSIONS AND SERIES
A sequence is also called a progression. We now study three important types of sequences:
(1) The Arithmetic Progression,
(2) The Geometric Progression,
(3) The Harmonic Progression.
Arithmetic Progression. Def. (A.P)
A sequence is

BINOMIAL THEOREM
A Binomial Expression
Any algebraic expression consisting of only two terms is known as a binomial expression. It's expansion in
power of x is known as the binomial expansion.
2
For example: (i) a + x
(ii) a + 1
(iii) 4x 6y
x2
Binomial Th

MENSURATION
Introduction
Mensuration is a branch of mathematics which concerns with the measurement of lengths, area and volume
of the plane and solid figures.
Area
The area of a plane region bounded by a simple closed curve is the magnitude or the measur

TRIGONOMETRY
Angle Measurement system
In the Sexagesimal system of measurement of a right angle is divided in to 90 equal parts called degrees.
Each degree is divided into 60 equal parts called minutes, and each minute into 60 equal parts called
seconds.

LIMITS
Let y = f(x) be a given function defined in the neighbourhood of x = a, but not necessarily at the point x = a.
The limiting behaviour of the function in the neighbourhood of x = a when |x a| is small, is called the limit of
the function when x app

QUADRATIC EXPRESSIONS
Quadratic Equations
Quadratic Polynomials: A polynomial of degree 2 is called a quadratic polynomial. Given form of quadratic
2
polynomial is ax + bx + c where a, b, c are real numbers such that a 0 and x is a variable.
Zeros of a Qu

MATRICES AND DETERMINANTS
Definition
A rectangular array of symbols (which could be real or complex numbers) along rows and columns is called a
matrix.
Thus a system of m n symbols arranged in a rectangular formation along m rows and n columns and
bounded

CO-ORDINATE GEOMETRY
INTRODUCTION
To locate a point (say, an object) on a plane surface (say, floor), we need to take two reference straight lines
in the plane which are perpendicular to each other (i.e., two mutually perpendicular edges of the floor).
C

Lecture 11
Solid solutions and
Ionic crystals
Recap
Voids in HCP and BCC
Estimated the total number of voids per atom/per cell
Void characteristics, estimated the void sizes
Summary of voids in HCP
HCP voids
Position
Voids / cell
Voids / atom
Tetrahedral

Lecture 6
Crystal Geometry
Recap
Baravis lattices
Understood the mystery of missing Bravais
lattices
Key characteristics associated with the
formation of a crystal: No. and Kind of atoms,
Orientation, internuclear spacing
Crystals: Brass, NaCl, Diamond
Tw

Lecture 29
Diffusion in
crystalline solids
Announcements
Next class will be on 19th Oct., Wednesday
No class on 14th and 18th Oct.
Minor-II Syllabus: Defects, phase diagrams
and diffusion (Lecture#16 to 29)
Minor-II: Seating plan will be uploaded on
Moodl

Lecture 13
Structure of silica
and Polymers
Structure of Silica
Crystalline Silica
Amorphous Silica
Low coefficient of thermal expansion, piezoelectric
material
Tetrahedral bonds
Network Modification by addition of Soda
+ Na2O =
Na
Na
Modification leads t

Lecture 24
Phase Diagrams
Recap
Unray diagram of Fe
Gas
Gibbs Phase Rule
P+F=C+2
P+F=C+1
Liquid
(BCC)
(FCC)
(BCC)
(HCP)
Isomorphous System
Liquid (solution)
Liquidus
Melting temperatures
of A and B
T
Solidus
Solid + Liquid
Alloy melts over range
of te

Introduction to Materials
Science and Engineering
1
2
Modern smartphones use surprisingly bad
alloys with insufficient strength and stiffness.
3
Dramatic Material Failure
Fuselage failure in the air
Deformed railway tracks due
to heat expansion of the ste

Lecture 28
Diffusion in
crystalline solids
Mathematical models of Diffusion
Atomisitic mechanism of Diffusion
Introduction
Diffusion importance
Oxidation of metals
Diffusion bonding
Hardening of steels
Creep
Doping
Many other processes
Introduction
We hav

Lecture 18
Crystal
imperfections
Recap
Line defects: Dislocations (defects not in thermodynamic
equilibrium, tendency to leave crystal)
Dislocation is a boundary between slipped and unslipped
part of the crystal lying over the slip plane
Slip plane con

Lecture 12
Ionic Solids
IONIC SOLIDS
Local coordination- Long range arrangement- Ionic crystal
(how many anions surround
a cation)
Rules for Local packing geometry (stable configuration)
1. Anions and cations considered as hard spheres always
touch each o

Lecture 16
Crystal
imperfections
Ideal crystals
Real crystals
Real materials are made of real crystals.
Real crystals will have imperfections or detects in them
An important observation
Imperfections in crystals occupy the volume
which is just about a sma

Lecture 19
Crystal
imperfections
Recap
Screw dislocation
Mixed dislocation
Recap
Relationship between t and b
Positive edge dislocation
t
b
Negative edge dislocation
b
t
b
t
Positive Screw
Negative Screw
b
t
0
180
Key properties of dislocations
A disloca

PLANE GEOMETRY
LINES AND ANGLES
Linear axiom 1: If sum of two adjacent angles is equal to 180, then the non-common arms of angles form a
straight line.
If AOB + BOC = 180, then AC is a straight line passing through O.
A
B
O
C
Linear axiom 2: If a ray is