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CERAMICS
7th group member :
Firda Ramadhena
112122239
Emeral Sakinah
Dinar
Prima Annisa Karunia 112121184
CERAMICS
 Ceramic Materials
Ceramic materials are inorganic and non-metallic materials
that can be composed also of metal and non-metal materials.
Because it has certain properties that are difficult processed and
avoided like the fragility of nature, then this material development
is quite slow.
The most important element that ceramic materials can be
processed into industrial materials which is good because in
general has excellent properties, such as:
1. Strong
2. Hard
3. Stable in high temperature.
By having important properties above, the ceramic materials
such as Silicon Carbide (SiC) or Silicon Nitride (Si3N4) can be used
as a base turbine and motor. They are formed of materials in ionic
and covalent bonding.
 Characteristic
Properties and main characteristics of ceramic materials can be
summarized as follows:
1. Hard
2. Fragile
3. Has a high melting temperature
4. Electical Isolator
5. A poor conductor of heat
6. Has a stable chemical composition
7. Has a high compressive
8. Properties retain heat stable
 Scope
This material as a raw material for a wide range industries, such as:
1. Household appliances
2. Cookers furnace equipment
3. Irrigation pipes
4. Glassware equipment
5. Refractory goods
6. Tooling machines
7. Electronic materials
8. Aviation and armament
Ceramic Phases
Generally ceramic phase has a crystalline structure,
only difference with the element of metal crystals,
crystalline ceramics do not have much free electrons.
This is because the electrons divided by the adjacent atoms.
Or is because the electrons move from one atom
to another atom and form ionic bonds.
Because the ionic bonds the ceramic material has
a high stability.
Tetrahaden crystal SiO4
structure is the basis for the
construction of various types of
crystalline silicate ceramic
materials.
Atom bonding ceramic materials are stronger than metal,
because the chemical reactions take place more slowly.
In general, the crystal structure of the
ceramic material is more complicated
when compared with the crystal
structure of the metal.
The picture is a form of cristobalite SiO2 unit.
Crystal Ceramic Material
Wake ceramic crystals that occur from
metallic and non-metallic compounds most
simple is if the comparison between metallic and
nonmetallic elements as 1:1. Examples of these
compounds are molecules of MgO. 2 MgO
bonding electrons move from the metal to nonmetal, thus forming Mg2+ cations and anions O2-.
How the preparation of the main atom can have 3 ways,
as the following example:
Crystal Ceramic Build type AZ
WAKE OF CRYSTAL: ZnS
Coordination Numbers: 4
Constants Kisi: a = 4 (r + R)
WAKE OF CRYSTAL: NaCl
Coordination Numbers: 6
Constants Kisi: a = (2r + 2R)
WAKE OF CRYSTAL: CsCl
Coordination Numbers: 8
Constants Kisi: a = (r + R)
 The Number Of Coordinates And Radius Comparison
EXAMPLES OF CERAMIC CRYSTAL
STRUCTURE
EXAMPLES OF CERAMIC CRYSTAL
STRUCTURE
A. CRYSTAL STRUCTURE OF CESIUM CHLORIDA (CsCl)
B. CRYSTAL STRUCTURE OF NATRIUM CHLORIDA (NaCl)
C. CRYSTAL STRUCTURE OF ZINK SULPHUR (SnS)
D. CRYSTAL STRUCTURE OF FLUROIT
E. CRYSTAL STRUCTURE OF WURTZITE
COORDINATES OF ATOM
CRYSTALCERAMIC MATERIAL
ELECTRON MAGNETIC PROPERTIES
OF CERAMICS
• Ceramic materials disseminated to electromagnetic circuits, this is
because the constant dielectric this material is high, even at the
moment of the transition elements are almost all semiconductors.
• There are a variety of oxides which acts as an insulator is good,
because the valence electrons of the metal atoms move on a
permanent basis to the oxygen atoms to form ion O2-
examples of phase binair diagram
THE TRANSFORMATION OF COMPOUND
CERAMIC
Ceramic Crystal type SiO2 shape : tetrahedder silica can have
various forms of alotropi, when the temperature rises, the silica will
change from :
The graph of the equilibrium is affected by the
pressure and temperature
THE TRANSFORMATION OF
COMPOUND CERAMIC
The transformation from crystalline to the crystalline form of a shift
transformation, where the transformation of this form is identical to the
reaction martensit. Silica with drastically changed the structure of the
Crystal due to distortion of the unit cell on the small contiguous parts or
from the nearest neighbor. This kind of transformation also occurs in
cristobolite and trydimite.
Transformation between silica and tridimite, with the cristobolite
transformation of the renewal (recontructive). Recontructive
transformation, requiring splitting of bonding between atoms and formed
a major change in crystal structure. The transformation this form requires
greater energy, the growing of grains crystals, and runs slower than on
the transformation of the shift.
THE TRANSFORMATION OF COMPOUND CERAMIC
The CaO-SiO2-Al2O2 tertiary phase diagram
THE TRANSFORMATION OF COMPOUND CERAMIC
The transformation of the shift gives rise to a linear expansionshaped dimensions and for sufficiently large compared to the sislika
that occurred on the glass, look at pictures 2.8.2 below :
CRYSTAL DEFECTS
POINT DEFECTS
HANDICAP LINE
DISABLE FIELDS
POINT DEFECTS
• Defects occur on events intersial or subtitusional, which is the
replacement of one atom to another.
•
Example: a ceramic compound at equilibrium NiO-MgO or
orthosilikat compounds such as : (Mg,Fe)2 SiO4 here ions mg or fe
acts of mutual substitution.
HANDICAP LINE
• This form of Disability line defect known as very popular name is
“dislocation”. Like many of the defects occur in compounds such as
LiF, Al2O3 and crystal MgO.
• Although at high temperatures, a ceramic material retains the
properties of the ' brittle ' before the case shifts atoms to be plastis
deformation.
DISABLE FIELDS
For example the events binding molecules of gas into the
surface of the material and this can serve meredusir energy surface.
Of foreign ions on certain ceramic compounds will be attracted to
composition from the surface of the Crystal field and certainly will
change the composition of the material.
PROCESS
TECHNOLOGY
VISCOSITY
THEORY
FINE PARTICLE
(POWDER)
formation technique
homogenization
manufacturing
process
PRESSING
SLIP CASTING
EXTRUSION
JIGGERING
SINTERING
TECHNIQUE FOR MANUFACTURING SHEET
AND PLATE GLASS
a) Rolling
b) Floating the glass on molten tin.
Figure (a): Stating the process of rolling and heat treatment to end with annealling.
Figure (b): The pool of glass with hot and cold process and continues to annealling.
How glass is made?
PROCESSES FOR SHAPING CERAMIC CRYSTALINE
a. PRESSING
b. ISOTATIC PROCESSING
c. EXTURSION
d. JIGERRING
e. SLIP CASTING
GRINDING
Until 20 years ago, ceramic material only known on the electrical
energy industry, because as an excellent insulator. Now known and
processed certain advantages such as: hard, refractory, insulation
and has a stable chemical composition. Hard materials are
processed because of violence and brittleness higher than metal, has
now managed to take the place as a superior components for :
a. CUTTING TOOLS
b. MECHANICAL PARTS.
CERAMIC MATERIALS FOR
HIGH TEMPERATURE HEAT EXCHANGES
Operation process of heat exchanges with temperatures
above 1000˚ C requires a material with excellent mechanical
properties. The properties include: strength of materials in high
temperature, High heat impact, creep and heat fatigue resistance.
The Material has mechanical properties above are just generally
owned by: ceramic monooksida. To get the materials ready for use
must be processed by sintering, both normal sintering and hot
presure pressurized sintering.
Ceramic materials are resistant to heat load caused by the
effects of heat flows from one side of the wall to the other side of
the heat exchange.
FISTON CERAMIC ENGINE.
In 1989 Isuzu Motor Co. Ltd., announced that it will begin to enter the
market a passenger vehicle which is driven by a piston engine of the
ceramic material.
presented a comparison of
output/thermal efficiency on
Ceramic Methanol engines