This document provides an outline for a lecture on imperfections in solids. It will cover point defects like vacancies and self-interstitials, impurities and solid solutions, linear defects like dislocations, and interfacial defects such as grain boundaries and phase boundaries. The goal is for students to understand different types of crystalline defects and how they influence material properties. Imperfections are an important factor in determining behaviors like yield strength and how metals respond to alloying.

1. MME 323: MATERIALS SCIENCE
WEEK 5 :
IMPERFECTION IN SOLIDS*
Adhi Primartomo, PhD
Email: primartomo_a@jic.edu.sa
Office: Room 191 – JIC Academic Building
* Source: Materials Science and Engineering; 9th Edition; W.D.Callister;
Wiley; 2011
https://sites.google.com/site/primartomo/file-cabinet

2. ~ LECTURE OUTLINE ~
Chapter 5: Imperfections in Solids (page
143 - 165)*
• Why Study Imperfections in Solids?
• Introduction,
• Point Defects in Metals,
• Impurities in Metals,
• Solid Solutions,
• Dislocations-Linear Defects,
• Interfacial Defects.
2

3. ~ Week 5 Learning Objective ~
After studying this chapter, you should be able to:
• Define and classify the crystalline defects,
• Explain the different types of point defects and
calculate the temperature dependence of the
equilibrium number of vacancies,
• Describe the impurities in solids and solid solutions,
• Explain the different types of linier defects,
• Explain the different types of interfacial defects.
3

4. WHY STUDY IMPERFECTIONS IN SOLIDS?
(page 144)
Properties of materials are influenced by the presence of
imperfections.
4
Yield Strength of Pure Copper (Cu): 117 MPa
Important to have knowledge on types of imperfections and
roles they play in affecting the behavior of metals.
Mechanical properties of pure metals change significantly
when metals are alloyed.
Yield Strength of Brass (70% Cu & 30% Zn): 200 MPa

5. INTRODUCTION
(page 144)
5
Imperfection:
??
Crystalline defect/crystalline imperfection:
??
Types of crystalline defects: ??
• Point defects
• Linear defects
• Interfacial defects

6. POINT DEFECTS IN METALS
(page 144-145)
6
Vacancy: ??
Temperature dependence of the
equilibrium number of vacancies:
Self-interstitial: ??
Example problem 6.1:

7. IMPURITIES IN SOLIDS
(page 149-151)
Alloy:
??
7
A pure metal consists of only on type of atom just is not
possible, impurity are always present.
Solid Solution  ??
Solute:
??
Solvent:
??

8. IMPURITIES IN SOLIDS
(page 149-151)
8
Types of Solid Solutions:
Hume-Rothery Rules:
• Atomic Size
• Crystal Structure
• Electronegative
• Valences

9. DISLOCATIONS – LINEAR DEFECTS
(page 158-161)
9
Dislocation: ??
Edge Dislocation
Screw Dislocation

10. INTERFACIAL DEFECTS
(page 161-165)
10
Interfacial Defects: ??
Types of Interfacial Defects:
• External Surfaces: ?
• Grain Boundaries: ?
• Phase Boundaries: ?
• Twin Boundaries: ?