INTRODUCTION

AND

ATOMIC BONDING

• Introduction• Atomic Structure• Atomic Bonding

ISSUES TO ADDRESS...

• What promotes bonding?

• What types of bonds are there?

• What properties are inferred from bonding?

• What is materials science?

– Relationship between structures and

properties of materials.

What is materials engineering?

Structures – properties correlations

Design the structure of material to impart

desired properties

1

7

Example – Hip Implant• With age or certain illnesses joints deteriorate.

Particularly those with large loads (such as hip).

Adapted from Fig. 22.25, Callister 7e.

8

Example – Hip Implant

• Requirements

– mechanical

strength (many

cycles)

– good lubricity

– biocompatibility

Adapted from Fig. 22.24, Callister 7e.

9

Example – Hip Implant

Adapted from Fig. 22.26, Callister 7e.

10

Hip Implant

• Key problems to overcome

– fixation agent to hold

acetabular cup

– cup lubrication material

– femoral stem – fixing agent

(“glue”)

– must avoid any debris in cup

Adapted from chapter-opening

photograph, Chapter 22, Callister 7e.

Femoral

Stem

Ball

Acetabular

Cup and Liner

The Periodic Table• Columns: Similar Valence Structure

Adapted from

Fig. 2.6,

Callister 7e.

Electropositive elements:

Readily give up electrons

to become + ions.

Electronegative elements:

Readily acquire electrons

to become - ions.

giv

e u

p 1

eg

ive u

p 2

eg

ive u

p 3

e

inert

gases

accep

t 1e

accep

t 2e

O

Se

Te

Po At

I

Br

He

Ne

Ar

Kr

Xe

Rn

F

ClS

Li Be

H

Na Mg

BaCs

RaFr

CaK Sc

SrRb Y