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MATERIALS IN · PDF file 2014. 4. 13. · Materials in Practice Asst. Prof. Dr. Ayşe KALEMTAŞ akalemtas MATERIALS IN PRACTICE Asst. Prof. Dr. Ayşe KALEMTAŞ Office Hours: Friday,

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  • 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] mailto:[email protected] mailto:[email protected] mailto:[email protected] mailto:[email protected] mailto:[email protected]

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

    OBJECTIVE

     To provide a basic understanding of ceramic

    materials.

     To understand

     processing,

     properties,

     characterisation and

     design

    of ceramic materials.

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

    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).

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

    ISSUES TO ADDRESS

     What is ceramic?

     Classification of ceramic materials

     Processing of ceramic materials

     Properties of ceramic materials

     Typical applications of ceramic materials

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

    Classifications of Materials

    Materials

    Metals

    Polymers

    Ceramics

    Composites

    With technological

    progress, natural

    materials become

    insufficient to meet

    increasing demands

    on product

    capabilities and

    functions.

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

    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.

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

    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.

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

    Introduction to Ceramic Materials

    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

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

    Introduction to Ceramic Materials

     Bonding:

     Mostly ionic, some covalent.

     % ionic character increases with difference electronegativity.

    CaF2

    SiC

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

    Introduction to Ceramic Materials

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

    Introduction

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

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

    Introduction

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

    M ET

    A LS

    High density

    Medium to high melting point

    Medium to high elastic modulus

    Reactive

    Ductile

    C ER

    A M

    IC S Low density

    High melting point

    Very high elastic modulus

    Unreactive

    Brittle

    P O

    LY M

    ER S Very low density

    Low melting point

    Low elastic modulus

    Very reactive

    Ductile and brittle types

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

    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

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

    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.

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

    Ceramics Materials

    Non-uniform, cru

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