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FATİH SULTAN MEHMET VAKIF ÜNV.
Introduction to Materials Science
(Malzeme Bilimi)
BME 374
Prof. Dr. Fevzi YILMAZ
NATURE and STRUCTURE of
MATERIALS
INTRODUCTION

A "material" is defined as matter that has qualities which give it individuality
and by which it may be categorized. Thus all physical objects are composed of
matter.

"Matter" is anything that has mass and occupies space.

Matter exists in solid, liquid and gas states. (A "solid" is a sample of matter that
has a fixed volume and fixed shape; a "liquid" is a sample of matter that has a
fixed volume, but takes the shape of the container it occupies; and a "gas" is a
sample of matter that has neither a fixed volume nor a fixed shape.)

Engineering design and construction of safe, serviceable, and economic
structures are greatly dependent on the proper selection and use of materials.
NATURE and STRUCTURE of
MATERIALS

The internal structure of various materials is very useful in understanding how
and why different materials behave differently under various conditions.
NATURE and STRUCTURE of
MATERIALS
SUBSTANCES THAT FORM THE MATTER
Atom
Molecules
Compound
Matter
NATURE and STRUCTURE of
MATERIALS
Atom : An "atom" is the smallest structural unit of all solids, liquids,
and gases. In other words, it is the smallest particle of an element that
possesses the chemical and physical properties of that element.
Element: An "element" is a substance that cannot be broken down into
substances of simpler composition any further by chemical reactions. It
is composed entirely of like atoms having the same atomic number.
Molecules and Compounds: The smallest particle which matter can
be divided without destroying its identity and characteristic properties
is called a "molecule". It is the smallest particle of any matter that can
exist and still be that matter.
NATURE and STRUCTURE of
MATERIALS
Atomic Number and Atomic Mass (Atomic Weight)
 Atomic Number -- The number of electrons which surround a
neutral atom is termed "atomic number".
 Since the number of electrons in a neutral atom is equal to the
number of protons in it, atomic number may also be defined as
the number of protons in its nucleus.
 Atomic Mass (Atomic Weight)
 Since the mass of an electron is very small (about 0.0005 as
much as the mass of a proton or a neutron) the mass of an atom is
considered to be nearly equal to the total mass of protons and
neutrons in the nucleus. In other words, the mass of an atom is
concentrated in the nucleus while the electrons account for most
of the volume.
NATURE and STRUCTURE of
MATERIALS
NATURE and STRUCTURE of
MATERIALS
ATOMIC BONDING

When the electron configuration it is seen that some elements such as Neon (Ne),
Argon (Ar), Krypton (Kr), Xenon (Xe) and Radon (Rn) all have eight electrons at
their outermost shells. These elements have a balanced electron configuration.

Helium (He) also has a balanced electron configuration since its total number of
two electrons are placed at the first shell.

All of those above mentioned elements do not tend to take an electron from another
element or lose an electron to another element.

Therefore, all these gases are named as inert (chemically inactive) or noble gases.

On the other hand, most elements, unlike the noble gases, need to achieve the
highly stable configuration of having eight electrons available for their outermost
shells.

This process takes place through one of the following procedures:
• Receiving extra electrons,
• Releasing electrons, or
• Sharing electrons.
NATURE and STRUCTURE of
MATERIALS

The first two of the above procedures (receiving electrons or releasing
electrons) produce ions with a negative charge or positive charge,
respectively. So the negative or the positive ions show coulombic *
attractions to other ions of unlike charges.

The third procedure (sharing electrons) lead to intimate association
between atoms.

All of these processes produce strong bonds (also called primary bonds, or
chemical bonds) between atoms.

In addition to the strong bonds, there are also always present some weaker
bonds (also called secondary bonds or van der Waals** bonds) among
atoms.

Thus the types of bonds that can form in materials can be divided into two
major categories;
I. The strong bonds (primary bonds),
2. The weak or secondary bonds (van der Waals bonds).
NATURE and STRUCTURE of
MATERIALS
The Strong Bonds (Primary Bonds)
 The types of strong bonds (also called Primary Bonds) are
grouped as
 ionic bonds,
 covalent bonds, and
 metallic bonds.
Ionic Bond
 Ionic bond is the chemical bond involving electron transfer
between atoms.
NATURE and STRUCTURE of
MATERIALS



Atoms of elements such as sodium which has one atom in
its outermost atom and calcium which has two atoms in its
outermost shell easily release these electrons and turn into
positively charged ions.
Likewise, those elements such as chlorine and oxygen, with
seven or six electrons in their outer shell, respectively,
easily receive electrons until they have eight electrons in
their outermost shell and become negatively charged ions.
Since there is always an attraction between the positively
and negatively charged materials, a strong bond is
established.
Fig.1.6 illustrates the ionization of the sodium and chlorine
atoms and the ionic bond between these two atoms.
NATURE and STRUCTURE of
MATERIALS

a negative charge possesses an attraction
for all positively charged particles, and a
positive charge possesses an attraction for
all negatively charged particles.

Consequently, sodium ions surround
themselves with negative chlorine ions,
and chlorine ions surround themselves
with positive sodium ions, the attraction
being equal in all directions.

The major requirement in an ionically
bonded material is that the number of
negative charges equal to the number of
positive charges.
NATURE and STRUCTURE of
MATERIALS
Covalent Bond

Covalent bond is the chemical bond involving electron sharing between atoms.

the electronic structure of an atom is relatively stable if there are eight electrons
in its outermost shell. (An exception is the first shell, which can be stable with
two electrons.)

Sometimes an atom may acquire the stable condition by sharing electrons with an
adjacent atom.

For example, hydrogen atom, H, has only one electron in its first shell and needs
a total number of two electrons in its first shell to become stable.

This condition is achieved by sharing an electron with another hydrogen atom as
shown in Fig.1.7(a).

Again, another example is the oxygen atom, 0, which has six electrons in its
outermost shell and needs a total number of eight electrons to become stable.
Such a condition is achieved by sharing four electrons with an adjacent oxygen
atom (two electrons from each) as shown in Fig.l.7(b).
NATURE and STRUCTURE of
MATERIALS



An atom can share one or
more electrons with an atom
of a different element too.
For example, fluorine, F, has
seven electrons in its
outermost shell and shares
one atom with the hydrogen
atom, H, to achieve a stable
condition as shown in
Fig.l.7(c).
Covalent bonds between two
atoms result in the formation
of diatomic molecules.
NATURE and STRUCTURE of
MATERIALS


Polyatomic (poly means many) combinations by covalent
bond are also common.
For example, carbon, C, which has four electrons in its
outermost shell shares four electrons with four hydrogen
atoms, H, and thus methane, CH4, is formed as simply shown
in Fig.1.8.
Figure 1.8 Covalent bond of methane
NATURE and STRUCTURE of
MATERIALS
Figure 1.9 Representation of ethane, C2H4, molecules:
(a) conventional representation
(b) electron pair representation
NATURE and STRUCTURE of
MATERIALS
Metallic Bond
 Metallic bond is the chemical bond involving the nondirectional sharing of delocalized
electrons.
 If there are only a few valence electrons (outermost shell electrons) within an atom,
these may be removed relatively easily while the balance of the electrons are held
firmly to the nucleus.
 Removal of the valence electrons forms a structure of free electrons and an ion core
consisting of the nucleus and nonvalence electrons.
 Thus in a metal structure there results positive cores of atoms and the electrons
removed from their atoms. These free electrons form an "electron "cloud.
 As a result, an attraction is developed between the positive ion cores and the free
electrons of the atoms in metal structures.
 For example, an atom of sodium element has one electron at its outermost shell and this
electron is easily removed leaving behind a positive ion core of sodium.
 When the other sodium atoms in the metal structure act the same way, there happens
many positive ions of sodium and a cloud of free electrons.
 Thus results an attraction among the positive ion cores of sodium and the free electrons.
 This is simply illustrated in Fig.1.10.
NATURE and STRUCTURE of
MATERIALS



Figure 1.10 Metallic bond in
sodium metal
The free electrons give the metal
its
characteristically
high
electrical conductivity, since
they are free to move in an
electric field.
They can transfer thermal energy
from a high to a low temperature
level; thus they are associated
with
the
high
thermal
conductivity behavior of metals.
They absorb light energy so that
they cause the metals to become
opaque to transmitted light.
NATURE and STRUCTURE of
MATERIALS
The Weak or Secondary Bonds (Van der Waals Bonds)
 Secondary or the van der Waals bonds are defined as
the atomic bonds that exist without electron transfer or
sharing.
 Actually, the mechanism of secondary bonding is
somewhat similar to ionic bonding, that is, this kind of
bonding results from the attraction of opposite charges.
 The main difference between the ionic bond and the
secondary bond is that, in the first one there is electron
transfer between atoms leading to a chemical bond
whereas in the latter one there is no electron transfer
and there exists physical bond.
NATURE and STRUCTURE of
MATERIALS




Interatomic, Interionic and Intermolecular Forces
Forces acting between atoms, ions, or molecules can be
of two kinds:
Forces of attraction and forces of repulsion.
While the forces of attraction pull the atoms, ions, or
molecules together, the forces of repulsion cause them
to be a certain distance away from each other.
When the attractive forces are equal to the repulsive
forces, an equilibrium is established. The balance
between attractive and repulsive forces is illustrated in
Fig.1.14 by using the ionic bond.
NATURE and STRUCTURE of
MATERIALS
Figure 1.14 Interatomic distances:
(a) The equilibrium spacing r0 , is the distance at which the attractive forces equal
the repulsive forces;
(b) The lowest potential energy occurs when r0 is the interatomic distance represents
the variation of potential energy with interatomic spacing.
NATURE and STRUCTURE of
MATERIALS

Assuming the potential energy of atoms to be zero
at an infinite distance of separation, the energy will
decrease as the atoms approach each other until the
potential energy reaches a minimum at an
equilibrium distance r0 where the forces of
attractions and repulsion are balanced.
NATURE and STRUCTURE of
MATERIALS




Any attempt to bring two atoms or molecules closer
together than the equilibrium distance (as in the case of
applying compression to materials) greatly increases the
forces of repulsion between them.
As the repulsive forces get very big, the attractive forces
that were providing cohesion between the atoms or
molecules can no longer hold them together and breaking
occurs.
When the atoms or molecules are pulled away from each
other (as in the case of applying tension to materials) the
spacing between them increases.
As a result, the potential energy increases leading to
breaking of the material.
NATURE and STRUCTURE of
MATERIALS
Generalization on the Relation of Some Material Properties
to the Atomic Bonding Characteristics


Since all materials are made of atoms, obviously the
properties of all materials are related to their atomic
structures. Thus the electron configuration, atomic number,
atomic mass, valence, ionization, atomic radius, interatomic
or intermolecular forces and the secondary forces are the
controlling aspects on the development of atomic or
molecular bonds and material properties.
The relation of some engineering properties of materials to
the atomic bonding characteristics may briefly be
summarized as follows:
NATURE and STRUCTURE of
MATERIALS
1. Density:
 Density is controlled by atomic weight, atomic radius, and
coordination number. Coordination number is a significant factor
because it controls the atomic packing.
2. Melting and boiling temperatures:
 Melting and boiling temperatures can be correlated with the depth
of the energy trough shown in Fig.1.14(b ).
 Atoms have minimum energy at a temperature of absolute zero, and
this corresponds to the bottom of the energy trough.
 Increased temperatures raise the energy and cause the atoms to
separate themselves.
 A greater depth in energy trough means that a higher energy is
required to separate the atoms leading to a higher melting
temperature for the material.
NATURE and STRUCTURE of
MATERIALS
3. Strength:





Strength is correlatable with the height of the sum curve (shown with
dotted line) in Fig.1.14(a).
That force, when related to the cross-sectional area, gives the stress
to separate atoms.
Deeper energy trough occurs when the interatomic forces of
attractions are higher.
Since deeper energy trough also leads to higher melting points as
explained above, it can be observed that materials with high
melting points are often the stronger (harder) materials.
In contrast, in materials with weaker bonds, generally there is a
correlation between softness and low melting point.
NATURE and STRUCTURE of
MATERIALS
4. Modulus of elasticity:
 The modulus of elasticity can be calculated from the slope of the sum
curve of Fig.1. 14(a), as shown in Fig.1.15.
 At the equilibrium distance r0 , the net force P is zero, and dP/dr relates to
stress to strain.
 For deeper energy troughs (for stronger materials), the slope of this sum
curve increases.
 Extreme compression or extreme tension raise or lower the modulus of
elasticity, respectively.
Figure 1.15 Slope of sum curve of interatomic forces
NATURE and STRUCTURE of
MATERIALS
5. Thermal expansion:





Thermal expansion is related to the atomic packing factor
and vary inversely with the melting temperatures.
Higher melting point materials have deeper and therefore
more symmetrical energy troughs.
Their mean interatomic distance increase less with a given
change in thermal energy.
Lower-melting point materials have less deeper and less
symmetrical energy troughs.
Thus they have higher thermal expansion.
NATURE and STRUCTURE of
MATERIALS
6. Electrical conductivity:

Electrical conductivity is dependent on the type of atomic bond.

Ionically or covalently bonded materials are extremely poor conductors,
because the electrons are not free to leave the atoms.

On the other hand, in metallically bonded materials, the free electrons
easily move and conduct electricity.
7. Thermal conductivity:

As explained for electrical conductivity, because of the electrons not being
able to move freely in ionically or covalently bonded materials, the thermal
conductivity is poor too.

Since the electrons are free to move in metallically bonded materials,
thermal conductivity is higher.
NATURE and STRUCTURE of
MATERIALS
8. Optical properties:

Metallically bonded materials become opaque to transmitted light
since the freely moving electrons can absorb the light energy.
9. Chemical properties:



In general, chemical properties are related to the valence electrons
and formation or disruption of bonds.
Among the various types of chemical reaction, the corrosion reaction
is probably the most significant in engineering.
In corrosion, the separation of a metallic ion from the metal involves
the removal of valence electrons from the outermost shell of the
atom.
NATURE and STRUCTURE of
MATERIALS
ATOMIC ARRANGEMENTS IN MOLECULAR,
AMORPHOUS, AND CRYSTAL STRUCTURES


The way that the atoms are arranged in a material is a
major factor that affects the formation of its structure and
the properties it possesses.
Atomic arrangements may be classified as follows:
• Molecular structures,
• Amorphous structures, and
• Crystal structures.
NATURE and STRUCTURE of
MATERIALS
Molecular Structures and Atomic Arrangements




As previously defined, a molecule is the unit of matter that is
formed between two or more atoms which are strongly bonded
together.
The atoms in a molecule are generally bonded to each other by
covalent bonds.
Thus intramolecular attractions are very strong.
In other words, "a molecule is a discrete group of atoms
where the atoms are held together by primary bonds".
NATURE and STRUCTURE of
MATERIALS

Although the atoms that compose a molecule are held together by strong bonds,
these discrete groups of atoms, the molecules, are attached to each other by the
weak secondary bonds.

Therefore, the molecular solids are soft because the molecules in such solids can
slide past each other with small stress applications.

In addition, molecular compounds have lower melting and lower boiling
temperatures compared with other materials.

Structure of some simple molecules have been already shown in Fig.1.16. Some
molecules have large numbers of atoms (as many as several thousand).

Whether the molecule is small like CH4 (methane), or much larger than that like
pentatriaconte, the bonds between the atoms of all molecules are strong and the
bonds between the molecules are weak secondary bonds.
Figure 1.16 Molecule with over 100 atoms
NATURE and STRUCTURE of
MATERIALS








A single unit molecule is called "monomer".
A monomer is the building block of a long chain or network molecule.
Fig.1.17(a) illustrates several unit molecules (monomers) of C2H4 (ethylene).
Molecular structures that are made up of many repeating units or mers are called
polymers.
Polymerization reactions occur by two main mechanisms: addition polymerization and
condensation polymerization.
Fig.1.17(b) shows a polymer containing many C2H4 mers, or units.
The word "poly (many)" as a prefix to the name of the particular molecule. Polymer
molecule consisting of vinly chloride mers, C2H3Cl, is called polyvinylchloride, PVC.
In construction of this polymer, the original double bond of ethylene monomer seen in
Fig.1.17(a) is broken to form two single bonds and thus the adjacent mers are connected
to each other. Thus a large molecule is formed.
Figure 1.17 Addition polymerization of ethylene:
(a) Monomers of C2H4 ethylene; (b) Ethylene
polymer formed by connection of many ethylene
mers
NATURE and STRUCTURE of
MATERIALS




Isomers -- In molecules of the same composition, more
than one atomic arrangements are usually possible.
Variations in the structure of molecules with the same
composition are called "isomers".
Fig.1.18 illustrates an example of isomers of propyl
alcohol, the normal propyl alcohol and isopropyl alcohol.
Although the compositions of these two alcohols are same,
their structures are different.
Figure 1.18 Isomers of propanol:
(a) Normal propyl alcohol;
(b) Isopropyl alcohol
NATURE and STRUCTURE of
MATERIALS
Amorphous Structures and Their Atomic Arrangements
 « Amorphous» means having no definite form.
 While the crystal structures have an ordered and three dimensional, geometric
arrangement that repeats itself the amorphous materials lack the repetitive pattern
of crystals.
 Fig.1.19 shows the general arrangements of atoms in a crystalline solid and in
amorphous materials such as liquids and gases.
 Besides the gases and liquids, some solids such as glasses, tars and asphalts have
amorphous structures too.
Figure 1.19
Arrangements of Atoms in
(a) A crystalline solid,
(b) A liquid, and
(c) A gas
(a)
(b)
(c)
NATURE and STRUCTURE of
MATERIALS








Gases -- There is no structure in a gas other than the structure of
individual molecules that it contains.
Each atom or molecule in the gas is quite far from other atoms or
molecules.
Therefore, they are free to move independently.
Since the atoms or molecules in a gas are free to move
independently, a gas which
fills an available space exerts pressure on its surroundings.
Liquids -- Like gases, liquids are fluids that do not have the
long-range repetitive pattern of crystals.
However, unlike gases, the atoms are not very far from each
other and they are not independent. In a way, the arrangements of
atoms show some similar characteristics to that of a crystal.
The difference between the atomic arrangements in crystal
structures and liquids is that, crystal structures have a crystalline
pattern of long-range order and the liquids have a short-range
structure in which the interatomic distances between first
neighbors are fairly uniform.
NATURE and STRUCTURE of
MATERIALS

Glasses -- Glasses are non crystalline solids.
They have a short range structure in which the
interatomic distances between first neighbors are
fairly uniform.

In other words, they lack long range order of
their atoms.

At sufficiently high temperatures they form true
liquids and increase their volume.

Volume changes and expansion characteristics
of glasses are shown in Fig.1.20.

The term "glass" applies to all materials which
have the expansion characteristics shown in that
figure.

Glasses may be either inorganic or organic.
Figure 1.20
Volume changes in glasses
NATURE and STRUCTURE of
MATERIALS





As can be seen in Fig.1.20, a glass is in liquid form at
a sufficiently high temperature.
The atoms have freedom to move around and respond
to shear stresses.
When it is super cooled below the melting
temperature Tm, thermal contraction takes place.
This contraction is caused by atomic rearrangements
which produce more efficient packing of atoms.
Below a certain temperature called fictive temperature
Tf, no further rearrangements of atoms takes place and
only further contraction is caused by reduced thermal
vibrations of atoms.
NATURE and STRUCTURE of
MATERIALS
Crystal Structures and Their Atomic Arrangements
 Crystals
are the structures that consist of regular
arrangements of atoms that have repeating patterns in three
dimensions.
 Most engineering materials have crystalline structure.
 The repeating three-dimensional pattern in crystals is due to
atomic coordination within the material.
 This pattern sometimes controls the external shape of the
crystals.
 The smallest volumetric unit that consists of regular
arrangements of atoms is called a "unit cell".
 All crystals are made of repeating patterns of unit cells.
NATURE and STRUCTURE of
MATERIALS
Crystal Systems and Crystal Lattices

Atomic packing in all crystals may take one of the seven crystal patterns
(systems) the names and geometry of which are shown in Table 1.4.
Trigonal = Rhombohedral
NATURE and STRUCTURE of
MATERIALS
Phases, Compositional Variations and Impure Phases
 The term "phase" is defined as "a structurally homogeneous part of a
material system".
 Some metals, such as copper and zinc do not contain any foreign elements in
their structure; they are pure.
 On the other hand, there are some metals that are not pure at all.
 In some cases, foreign elements are intentionally added to a material for the
purpose of improving its properties.
 For example, inclusion of zinc element to copper produces brass. In such a
case, the foreign element becomes a part of the crystal lattice of copper while
the copper still maintains its body centered cubic structure.
 If an addition becomes an integral part of the solid phase, the resulting phase
is called a solid solution.
+
=
NATURE and STRUCTURE of
MATERIALS

2 grains in a solid.
Figure 1.32 Grain boundary
 The shape of a grain in a solid is usually controlled by
the presence of surrounding grains.
 The atoms of any particular grain are arranged with
one orientation and one pattern characterized by the
unit cell.
 However, there exists a transition zone (grain boundary)
between two adjacent grains and at this zone the atoms
are not aligned with either grain.
 The grain boundary is considered to be two
dimensional, although it actually has a finite thickness
of 2 to 10 or more atomic distances.
 The mismatch of the orientation of adjacent grains
produces a less efficient packing of the atoms along the
boundary.
 Therefore, the atoms along the boundary have a higher
energy than those within the grain. So those atoms at
the grain boundaries can easily be separated from the
grains.
NATURE and STRUCTURE of
MATERIALS

Grain boundary samples
MECHANICAL PROPERTIES





Shape changing property is used as indicator of ductility, the ability
of a material to be elongated in tension.
Brittleness is having hardness and rigidity but little tensile strength;
breaking readily with a comparatively smooth fracture, as glass.
The ability of a metal to deform plastically and to absorb energy in
the process before fracture is termed toughness.
In materials science, fracture toughness is a property which
describes the ability of a material containing a crack to
resist fracture, and is one of the most important properties of any
material for many design applications.
Hardness is a measure of how resistant solid matter is to various
kinds of permanent shape change when a compressive force is
applied.
MECHANICAL PROPERTIES
MECHANICAL PROPERTIES
a.) Ductile
b.) Brittle
MECHANICAL PROPERTIES
.
PHYSICAL PROPERTIES





The modulus of elasticity (also known as the elastic modulus, the tensile
modulus, or Young's modulus) is a number that measures an object or
substance's resistance to being deformed elastically (i.e., non-permanently)
when a force is applied to it.
In physics, thermal conductivity (often denoted k, λ, or κ) is the property of
a material to conduct heat.
Thermal expansion is the tendency of matter to change in shape, area,
and volume in response to a change in temperature.
Heat capacity or thermal capacity is a measurable physical quantity equal
to the ratio of the heat added to (or removed from) an object to the
resulting temperature change.
Fatigue limit, endurance limit, and fatigue strength are all expressions
used to describe a property of materials: the amplitude (or range) of cyclic
stress that can be applied to the material without causing fatigue failure.
FIGURE OUT - COMPARISON
Yield Strength
σys= 370MPa=37 kg/mm2
Elastic Modules
E=216GPa=216.000.MPa=
216.000.106Pa=
=216.000.106 N/m2=
=21.600.106 kg/m2=
=21.600 kg/mm2
Kıc-fracture toughness
High Kıc crack(a) tolerant
Kıc= σ √a= MPa.a1/2= MPa.m1/2
Specific heat (J/kg.K cal/g.0C)
Air=0,2cal/g.0C
Water=1 cal/g.0C
Soil= 0,3-1,5 cal/g.0C
metal<seramic<polymer
Th. Conductivity (W/m.K)
Polymer, elostomer= 10-3. metal
Th.Expansion (10-6/0C, 10-6/K)
P,E = 10 . metal
Ceramic 0,5.10-6/0C
Polymer 50.10-6/0C -400. 10-6/0C
Invar 0,7. 10-6/0C
MATERIALS
Fiat: Naylon 8, Çelik 0.5, Alüminyum 4, Titanyum 26, Cam 0,8
Yoğunluk, Özgül Kütle: Cam2.5, Titanyum 5,Alümin. 2.7, çelik 7.8
Teknik Özellikler
Elastik Modül, Direngenlik: Çelik 210,Alümin.75, PVC 3, Naylon3
% Uzama: Naylon 1000, PC 100, Çelik25, Cam 0
Kırılma Tokluğu: Cam 0.6, Çelik 60, Titany.80, Polimer komp. 10
Sertlik:PVC10,Çelik 400, Cam 460
Akma Mukavemeti: Cam 30, Çelik1000, PVC45
Servis: PVC-20-70,Çelik-70-360, Cam-250-250
Özgül ısı: Cam900,Çelik480,PVC1400,
Termal iletkenlik: Cam1,Çelik50, Alümin.200, Polimer köpük0.05
Termal genleşme: Cam9.Çelik12, Alümin.20, Polimer köpük100
Ekolojik Özellikler
Enerji miktarı: Cam22,Çelik65, Alümin.275, Polimer köpük170
Cam-yüksek,Çelik-yüksek, Alümin.-yüksek, Polimer köpük-düşük
Estetik Özellikler
Düş.-yük. titreş:Cam7-8,Çelik9, Alümin.8-9, Polimer köpük2-3
Sönümleme-çınlama:Cam8-9,Çelik6-7, Alümin.5-8, Polim-köp2
Cam7-8,Çelik9, Alümin.8-9, Polimer köpük2-3
Cam5-6,Çelik9, Alümin.9-10, Polimer köpük8-9
Parlaklık:Çelik-%59,Alüminyum-%89
Geçirgen-opak:PC-optik kalite, Alüminyum-opak
Diğer polimerlere göre göreceli özellikler
Soğuğa dayanım
Korozyon direnci
Sönümleme
Yanma geciktiriciliği
Ağır
Sıcağa dayanım
Kayganlık
Sağlam
References


T. Y. ERDOGAN v. d., «Materials Science for Civil
Engineering», ODTU Yayıncılık, 2010, Ankara
M. ASHBY and K. JOHNSON, «Materials and
Design», Elsevier Butterworth Heinemann, 2006,
Amsterdam.