materials in practicesablon.mu.edu.tr/icerik/metalurji.mu.edu.tr/sayfa/kalemtas_a_materi… · d....

Materials in Practice Asst. Prof. Dr. Ayşe KALEMTAŞ Materials in Practice Asst. Prof. Dr. Ayşe KALEMTAŞ

MATERIALS IN

PRACTICE

Asst. Prof. Dr. Ayşe KALEMTAŞ

Office Hours: Friday, 16:30-17:30

[email protected], [email protected]

Phone: +90 – 252 211 19 17

Metallurgical and Materials Engineering Department

mailto:[email protected]







OBJECTIVE

To provide a basic understanding of ceramic

materials.

To understand

processing,

properties,

characterisation and

design

of ceramic materials.


REFERENCES

D. W. Richerson, "Modern Ceramic Engineering," Second

Edition, Marcel Dekker Inc., (1992).

W.D. Kingery, H.K. Bowen, and D.R. Uhlmann,

“Introduction to Ceramics”, John Wiley and Sons, 1976.

Reed, J. S., ”Principles of Ceramic Processing” John

Wiley&Sons, New York (1995).

Ring, T. A., "Fundamentals of Ceramic Powder Processing

and Synthesis", Academic Press, San Diego (1996).

Rahaman, M. N., "Ceramic Processing and Sintering",

Marcel Dekker Inc. (1995).


ISSUES TO ADDRESS

What is ceramic?

Classification of ceramic materials

Processing of ceramic materials

Properties of ceramic materials

Typical applications of ceramic materials


Classifications of Materials

Materials

Metals

Polymers

Ceramics

Composites

With technological

progress, natural

materials become

insufficient to meet

increasing demands

on product

capabilities and

functions.


What is "ceramic"?

• from Greek meaning: "burnt earth"

• non-metal, inorganic

• Ceramic materials are inorganic compounds consisting of metallic and nonmetallic elements which are held together with ionic and/or covalent bonds.


Introduction to Ceramic Materials

Ceramics are

inorganic, nonmetallic, solids, crystalline,

amorphous (e.g. glass), hard, brittle, stable

to high temperatures, less dense than

metals, more elastic than metals, and very

high melting.

Ceramics can be covalent network and/or ionic

bonded.



Ductile versus Brittle Fracture

Fracture Behavior: Very Ductile Modulate Ductile Brittle

Ductile Fracture is

Desirable

Ductile warning

before fracture

Brittle no warning

before fracture

% RA or %EL: Large Moderate Small



Bonding:

Mostly ionic, some covalent.

% ionic character increases with difference electronegativity.

CaF2

SiC


Introduction

A comparison of the properties of ceramics, metals, and polymers


Introduction

A comparison of the properties of ceramics, metals, and polymers

MET

ALS

High density

Medium to high melting point

Medium to high elastic modulus

Reactive

Ductile

CER

AM

ICS Low density

High melting point

Very high elastic modulus

Unreactive

Brittle

PO

LYM

ERS Very low density

Low melting point

Low elastic modulus

Very reactive

Ductile and brittle types


Historical Perspective

Stone Age: 2.5 million years ago

Pottery Age: 4000 B.C.E

Copper Age: 4000 B.C.E – 3000 B.C.E.

Bronze Age: 2000 B.C.E – 1000 B.C.E.

Foundation of metallurgy- Alloys of copper and tin

Iron Age: 1000 B.C.E – 1B.C.E.

Plastics Age: late 20th Century to current time

Semiconductor Age: late 20th Century to current time


Ceramics Materials

Ceramic Materials

Naturally occurring minerals Synthetic materials

their origin

locations in which they can be found

their relative abundance

Naturally occurring minerals require extraction,

which is often a regional industry located close to

abundant quantities of the natural deposit.

Most minerals need to go through some form of

physical or chemical processing before use. The

collective term for these processes is beneficiation.

When you understand how oxides are

manufactured, it will be clear why they are often

impure and why Si, Na, Ca are the major impurities.

borides (TiB2, BN, etc.)

carbides (SiC, B4C, TiC, etc.)

nitrides (AlN, Si3N4, TiN, etc.)

oxides (TiO2, Al2O3, etc.)

These ceramics are becoming more common,

but are generally expensive and desire special

processing environments.

For many nonoxides the main impurities are

often components of the starting material which

was not reacted, e.g., Al in AlN or Si in Si3N4.


Ceramics Materials

Non-uniform, crude materials from natural

deposits clays. (Montmorillonite, illite, etc.)

NATURAL RAW MATERIALS


Classification of Ceramics

Ceramic Materials

Advanced Ceramics Traditional Ceramics

Advanced ceramics

Made from artificial or chemically modified raw

materials.

Traditional ceramics

Mainly made from natural raw materials such as kaolinite (clay mineral), quartz and

feldspar.



Ceramic Materials

Advanced Ceramics

Structural Ceramics

Bioceramics

Ceramics used in automotive industry

Nuclear ceramics

Wear resistant ceramics (tribological)

Functional Ceramics

Electronic substrate, package ceramics

Capasitor dielectric, piezoelectric ceramics

Magnetic ceramics

Optical ceramics

Conductive ceramics

Traditional Ceramics

Whitewares

Cement

Abrasives

Refractories

Brick and tile

Structural clay products


Traditional Ceramic Products

Whitewares:

• Dinnerware

• Floor and wall tile

• Electrical porcelain

• Decorative ceramics

Cement:

• Concrete roads, bridges, buildings, dams, sidewalks, bricks/blocks

Abrasives:

• Natural and synthetic abrasives

Refractories:

• Brick and monolithic products used in iron and steel, non-ferrous metals, glass, cements, ceramics, energy conversion, petroleum, and chemicals industries, kiln furniture

Glasses:

• Flat glass (windows), container glass (bottles), pressed and blown glass (dinnerware), glass fibers (home insulation)

Structural clay products:

• Brick, sewer pipe, roofing tile



Clay pipes are sustainable

products and last longer than

other materials



Insulating brick

Refractory Brick


Processing of Traditional Ceramics

Minerals

Chemical processing

Powder Powder

processing

Green body

Sintering Dense/Porous

Compact

Final Product


Materials Tetrahedron

Microstructures Properties

Processing

Performance



Clay products – Main Components

Clay

Silica Feldspar



Clay products – Main Components

When mixed with water the crystals can easily slide over each other (like a pack of cards), and this phenomenon

gives rise to the plasticity of clays.

Provides plasticity, when mixed with water

Hardens upon drying and firing (without losing

the shape)

Adding water to clay

-- allows material to shear easily along weak

van der Waals bonds

-- enables extrusion

-- enables slip casting

Silica, SiO2, is mixed with clay to reduce shrinkage

of the ware while it is being fired, and thus

prevent cracking, and to increase the rigidity of the ware so that it will

not collapse at the high temperatures required for firing. Silica is useful for this purpose becasue

it is hard, chemically stable, has a high

melting point and can readily be obtained in a pure state in the form of

quartz.

Feldspars are used as a flux in the firing of

ceramic ware. When a body is fired, the

feldspar melts at a lower temperature than clay or

silica, due to the presence of Na+, K+ or Ca2+ ions, and forms a

molten glass which causes solid particles of

clay to cling together: when the glass solidifies

it gives strength and hardness to the body.

Clay

Silica

Feldspar


Cement and Concrete Manufacturing

Lime

Clay

Iron

Kiln

Gypsum

Clinker

Additions

Mill

Gravel

Cement

Admixtures

Sand

Water

Mixer



Ceramic Materials

Advanced Ceramics

Structural Ceramics

Bioceramics

Ceramics used in automotive industry

Nuclear ceramics

Wear resistant ceramics (tribological)

Functional Ceramics

Electronic substrate, package ceramics

Capasitor dielectric, piezoelectric ceramics

Magnetic ceramics

Optical ceramics

Conductive ceramics


Whitewares

Cement

Abrasives

Refractories

Brick and tile

Structural clay products


Ceramic Materials

The technology of ceramics is a rapidly developing applied science in

today’s world. Technological advances result from unexpected material

discoveries. On the other hand, the new technology can drive the

development of new ceramics.

Currently many new classes of materials have been devised to satisfy

various new applications. Advanced ceramics offer numerous

enhancements in performance, durability, reliability, hardness, high

mechanical strength at high temperature, stiffness, low density, optical

conductivity, electrical insulation and conductivity, thermal insulation

and conductivity, radiation resistance, and so on.

Ceramic technologies have been widely used for aircraft and

aerospace applications, wear-resistant parts, bio-ceramics, cutting

tools, advanced optics, superconductivity, nuclear reactors, etc.

M. Rosso, Ceramic and metal matrix composites: Routes and properties, Journal of Materials Processing Technology 175 (2006) 364–375


Advanced Ceramic Products


Ceramic Materials

OXIDES

The raw materials used for oxide ceramics

are almost entirely produced by chemical

processes to achieve a high chemical purity

and to obtain the most suitable powders for

component fabrication.

NONOXIDES

Most of the important nonoxide ceramics

do not occur naturally and therefore must

be synthesized. The synthesis route is

usually one of the following:

Combine the metal directly with the

nonmetal at high temperatures.

Reduce the oxide with carbon at high

temperature (carbothermal reduction) and

subsequently react it with the nonmetal.



Application

Cutting tools

Bearing, liners, seals

Agricultural machinery

Engine and turbine parts

Shielding, armour

Hig performance windows

Artificial bones, teeth

Property

Hardness, toughness

Wear resistance

Wear resistance

Heat, wear resistance

Hardness, toughness

Translucence, strenght

Wear resistance, strenght

Material

Alumina, SiAlON

Alumina, zirconia

Alumina, zirconia

SiC, Alumina, Si3N4

Alumina, B4C

Alumina, Magnesia

Zirconia, Alumina


Processing of Ceramics

* : Ceramic Materials: Science and Engineering, by C. Barry

Carter and M. Grant Norton, Springer, 2007, page 6.

A comparison of different

aspects of traditional and

advanced ceramics.*


Raw Material Selection Criterias

Raw material cost

Market factors

Technical process parameters

Performance of the desired product

Market price of the product


Design Objectives

Performance: Strength, Temperature

Manufacturing Techniques

Life Cycle Considerations

Cost


Other Ceramic Materials

Cements - Ceramic raw materials are joined using a binder that does

not require firing or sintering in a process called cementation.

Coatings - Ceramics are often used to provide protective coatings to

other materials.

Thin Films and Single Crystals - Thin films of many complex and

multi-component ceramics are produced using different techniques

such as sputtering, sol-gel, and chemical-vapor deposition (CVD).

Fibers - Fibers are produced from ceramic materials for several uses:

as a reinforcement in composite materials, for weaving into fabrics, or

for use in fiber-optic systems.

Joining and Assembly of Ceramic Components - Ceramics are

often made as monolithic components rather than assemblies of

numerous components.


Ceramic Materials


Ceramic Materials

Advanced

ceramic

application

tree

Limitations due to

- High cost

- Low toughness

- Low reliability M. Rosso, Ceramic and metal matrix composites: Routes and properties, Journal of Materials Processing

Technology 175 (2006) 364–375



Ceramic filter Foam ceramic molten metal filter

Ceramic Knife Ceramic Fiber Boards As The Heat Insulation



Ceramic Fiber Products

Ceramic fittings

Ceramic faucet valves with superior

wear resistance and sealing

performance.

Ceramics are used in various textile

machines as guide parts, thread

processing nozzles, oiling nozzles,

rollers and twister parts. Cutting and wear-resistant parts Alumina Ceramic Pipe Lining



http://aluminatechnologies.com/products.php



Ceramic seal rings, axial bearings and radial bearings ensure highly reliable operation and long service life

wherever fluids are pumped or gas is compressed.

Ball Heads Cup Inserts. For inserting

into the acetabular cup

Knee Joint Components.

Improved quality of life,

reduce wear and minimize the

risk of allergies.

High temperature wear

resistance industrial zirconia

advanced ceramic insulator

products



With its extensive material range and continuously growing production

expertise in the field of ceramic components for textile processing,

Biocompatible ceramic parts for

drug-delivery systems.

Sheer Veneers ZrO2-metal free

restorations



Bearing Rollers made from Silicon Nitride

In engine design or exhaust systems, in liquid or gas

circuits – automotive industry demands on seal

rings, bearings and sealing technology are especially

high. Technical ceramics ensure wear resistance,

temperature resistance and stability in these

aggressive environments.

Ceramic gas nozzles made of silicon nitride

Ceramic rollers



Inserts from CeramTec's latest generation of

ceramic cutting materials. Designed specifically

for high-performance machining of cast iron

materials.

The proven performance standard for

efficient machining with indexable inserts

made of ceramic cutting materials.

CBN indexable inserts (polycrystalline cubic boron nitride) for

efficient machining of cast iron materials and sintered steels for

turning, milling, boring and grooving.

Whether filtration, galvanization, water heating or soil analysis; fields of

application such as the chemicals industry, laboratories, electronics and

electrical engineering, environmental technology or foundry technology


Thanks for your kind

attention

THE END


Any

Questions

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