Chapter6 - Chapter 6 Noncrystalline and Semicrystalline...

Chapter 6
Noncrystalline and Semicrystalline
Materials
• Introduction
• Glass Transition Temperature
• Viscous Deformation
• Structure and Properties of Amorphous Oxide
Glasses
• Structure and Properties of Amorphous and
Semi-crystalline Polymers
• Structure and Properties of Rubbers and
Elastomers
• Metallic Glasses

Some Glass Forming Systems
• Elements S, Se, P
• Oxides SiO
2
, B
2
O
3
, P
2
O
5
, GeO
2
, AsO
2
• Halides BF
2
, AlF
3
, ZnCl
2
, Ag(Cl,Br,I),Pb(Cl
2
,Br
2
,I
2
)
• Sulfides As
2
S
3
, Sb
2
S
3
• Selenides Various compounds of Tl, Sn, Pb, As, Sb,
Bi, Si, and P
• Tellurides Various compounds of Tl, Sn, Pb, As, Sb,
Bi and Ge
• Nitrides KNO
3
-Ca(NO
3
)
2
and many mixtures
containing alkali and alkaline earth nitrates
• Sulfates KHSO
4
and many other binary and ternary
mixtures
• Carbonates K
2
CO
3
-MgCO
3
• Polymers Polystyrene, PMMA, polycarbonate, PET
• Metallic Alloys Au
4
Si, Pd
4
Si, (Fe-Si-B) alloys, Al-transition
metal rare earths

Specific Volume for a Variety of Materials
Liquid to glass solid
transformation in a pure
substance. The glass transition
temperature, Tg, is not an
equilibrium transformation
temperature.
Liquid to crystalline solid
transformation for a pure
substance. T
m
is an equilibrium
transformation temperature

The Effect of Cooling Rate on the Glass
Transition Temperature, T
g
Specific Volume
T
g1
T
g2
T
m
Temperature
T
1
.
T
2
.
T
1
.
T
2
.
Liquid Liquid
Solid
Glass
(Glassy behavior)
Super
Super -
cooled liquid
cooled liquid
(Rubbery behavior)
(Rubbery behavior)
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