Ceramics Flashcards
PRIMARILY CONSIST OF METALLIC
AND NONMETALLIC ELEMENTS
Ceramics
ALSO CALLED THE CLAY PRODUCTS
OR SILICATE INDUSTRIES
Ceramic industry
CERAMIC INDUSTRY ALWAYS HAVE __________ AS THEIR FINISHED MATERIAL IN A VARIETY OF PRODUCTIONS
SILICATES
Demand for materials:
-WITHSTAND HIGHER TEMPERATURES,
-RESIST GREATER PRESSURES,
-HAS SUPERIOR MECHANICAL PROPERTIES,
-POSSESS SPECIAL ELECTRICAL CHARACTERISTICS,
-OFFER PROTECTION AGAINST CORROSIVE CHEMICALS
When and where was the discovery of oldest known ceramic artifact
Early 28000 BC (Paleolithic period), Brno, Czech Republic
Oldest known ceramic artifact
VENUS OF DOLNÍ VĚSTONICE
In this location hundreds of clays representing ice age animals was discovered
Czech republic
15000 BC
Burnt claywares
Become engage wuth the arts of ceramics (5000BC)
Chinese and Egyptian
1920
PURE OXIDE REFRACTORIES,
METAL-BONDED OXIDES,
CARBIDES, NITRIDES, AND BORIDES
1924
Face brick attained 2.5 billion
1925
Common brick reached 7.6 billion
3 main raw ingredients ceramics
Clay
Feldspar
Sand
MORE OR LESS IMPURE HYDRATED ALUMINUM
SILICATES THAT HAVE RESULTED FROM THE
WEATHERING OF IGNEOUS ROCKS SUCH AS
FELDSPAR
Clay
PRODUCED
THROUGH
THE
HYDROLYSIS OF WEATHERING REACTIONS
OF IGNEOUS ROCKS
Clay
Different clay materials:
KAOLINITE (AL2O3 2SIO2 2H2O)
BEIDELLITE (AL2O3 3SIO2 H2O)
MONTMORILLONITE (AL2O3 4SIO2 H2O)
HALLOYSITE (AL2O3 2SIO2 3H2O)
CLAYS ARE ________ AND _______WHEN SUFFICIENTLY FINELY PULVERIZED
Plastic
Modable
CLAY IS WET, RIGID WHEN IT IS BEING _________
AIR-DRY
T&F. CLAY IS VITREOUS WHEN FIRED AT A SUITABLY HIGH TEMPERATURE
T
T&F. DIFFERENT CLAY BODIES “MATURE” AT SAME TEMPERATURES
F(DIFFERENT)
TERM USED TO IDENTIFY THAT AT A SPECIFIC TEMPERATURE, CLAY CAN BE FORMULATED TO PRODUCE NEW PRODUCTS
Mature
MOST BASIC CLAY MINERAL USED IN THE CERAMIC INDUSTRY
Kaolinite
Most abundant clay mineral
Kaolinite
BASED ON
MONTMORILLONITE CLAYS
Bentonite clay
THEY ARE USED TO SOME
EXTENT WHERE VERY HIGH PLASTICITY IS DESIRED
Bentonite clay
HELPS TO ACHIEVE THE REQUIRED PARTICULAR SIZE AND SIZE DISTRIBUTION OF RAW MATERIALS
Benefication
Benefication increase the clay content while whice decreasing the content of _________
Quartz
PROCESS OF BENEFICIATION OF CLAY CONSISTS OF:
Unit operation
ADDED AS THE APPROPRIATE
ADDITIONAL AGENTS USED TO CONTROL THE COLLOIDAL PROPERTIES OF
CLAY
Sodium silicate and aluminum
GROUP OF ALUMINOSILICATE MINERALS
THAT ALSO CONTAINS CALCIUM, SODIUM
AND POTASSIUM
Feldspar
MAKES UP MORE THAN HALF OF THE EARTH’S CRUST
Feldspar
MOST COMMON MINERAL IN THE EARTH’S
CRUST
Feldspar
3 common type of feldspar
POTASH FELDSPAR
SODA FELDSPAR
LIME
FELDSAPR
MOST COMMON TYPE OF FELDSPAR
Potash
Feldslar are greate importance as
Fluxing constituent
FORMS WHEN CLAY MINERALS ARE IN CONTANCT WITH EACH OTHER AND UNDERGOES METAMORPHISM
Mullite
T&F. PRESENCE OF FLUXES TENDS TO INCREASE THE TEMPERATURE OF THE FORMATION OF MULLITE AND INCREASES THE ATTAINMENT OF THE EQUILIBRIUM CONDITIONS
F(lower)
PROMOTES VITRIFICATION
Feldspar
TYPE OF MINERAL THAT NATURALLY CONSIST OF SILICA/ QUARTZ OR SIO2
Sand
Use for manufacturing light-colored ceramics
Sand with low iron content
150 TO 650°C
Dehydration or “chemical water smoking”
600 TO 900°C
Calcination
350 TO 900°C
Oxidation of ferrous iron and organic matter
900°C AND
HIGHER
Silicate formation
MOST ESSENTIAL INGREDIENT
Clay (in form of kaolinite)
AS THE TEMPERATURE OF THE AMORPHOUS ALUMINA (KAOLIN) CHANGES TO 940 C, IT FORMS A CRYSTALLINE FORM CALLED
Gamma alumina
AT ABOUT 1000 C, THE ALUMINA AND
SILICA COMBINE TO FORM
Mullite
THE TEMPERATURE EXCEEDS TO MORE
THAN 1000 C, THE MULLITE IS
CONVERTED TO A CRYSTALLINE FORM
CALLED
Cristobalite
DEGREE
OF VITRIFICATION DEPENDS UPON
THE FOLLOWING FACTORS:
Amount of refactories and flux oxide
Time
Temperature
GENERIC TERM FOR CERAMIC PRODUCTS WHICH ARE USUALLY WHITE AND OF FINE TEXTURE
Whitewares
SOMETIMES CALLED SEMI-VITREOUS DINNERWARE, WHICH ARE POROUS AND
NON-TRANSLUCENT WITH A SOFT GLAZE
Earthware
VITRIFIED TRANSLUCENT WARE WITH A MEDIUM GLAZE THAT CAN RESIST
ABRASION TO A DEGREE AND USED FOR NONTECHNICAL PURPOSES
Chinaware
INCLUDES CHEMICAL, INSULATING, AND DENTAL PORCELAIN, VITRIFIED
TRANSLUCENT WARE WITH A HARD GLAZE, AND CAN RESIST ABRASION TO
THE MAXIMUM DEGREE
Porcelain
SCRATCH/DAMAGE/PILAS
Abrasion
FORMERLY MADE FROM CLAY, USUALLY POROUS; HENCE, HAS VITREOUS COMPOSITION, PREFIRED AND SIZED VITREOUS GROG IS SOMETIMES INCLUDED WITH THE TRIAXIAL COMPOSITION
Sanitary ware
OLDEST OF CERAMIC WARES, WAS IN USE LONG BEFORE
PORCELAIN WAS DEVELOPED
Stoneware
REGARDED AS A CRUDE PORCELAIN MADE FROM
A POORER GRADE OF NOT CAREFULLY FABRICATED RAW MATERIALS
Stoneware
3 line of production of porcelain:
Wet process porcelain
Dry process porcelain
Cast porcelain
USED FOR PRODUCTION OF FINE-GRAINED
HIGHLY GLAZED INSULATORS FOR HIGH VOLTAGE SERVICE
Wet process porcelain
PROCESS EMPLOYED FOR RAPID PRODUCTION
OF MORE OPEN-TEXTURED LOW-VOLTAGE
PIECES
Dry process porcelain
NECESSARY FOR THE MAKING OF PIECES THAT
ARE EITHER TOO LARGE OR TOO INTRICATE
FOR THE OTHER TWO METHODS
Cast porcelain
PLASTIC CLAY IS PRESSED INTO OR ON A SINGLE REVOLVING MOLD
Jigging
PROCESS OF VITRIFICATION FOR THE PRODUCTION
OF PORCELAIN IS DONE THROUGH A
One fire process
T&F. GLAZING IS NOT IMPORTANT IN THE PRODUCTION OF WHITEWARES
F(IMPORTANT)
THIN COATING OF GLASS THAT IS MELTED AND IS APPLIED THE SURFACE OF THE POROUS CERAMIC WARE
Glaze
2 ingredients of glazing
Refactory materials
Flux
TECHNICAL TERM FOR THE FIRING OF
THE GLAZE INSIDE THE KILN
Glost firing
LOW-COST BUT VERY DURABLE PRODUCTS
Heavy clay products
PROCESS OF GLAZING IN SEWER PIPE
AND DRAIN TILE BY THROWING SALT UPON
THE KILN FIRE FOR IT TO REACT AND FORM THE FUSIBLE COATING OR THE GLAZE
Salt glaze
COMPRISES COMMON AND FACE BRICK
Buliding clay
STANDARD BRICK TYPE AND THE MOST ABUNDANTLY USED BUILDING MATERIAL IN MODERN CONSTRUCTION
Common bricks
HAVE A MORE AESTHETICALLY
PLEASING APPEARANCE
Face bricks
UNIFORM IN COLOR AND SMOOTHER IN TEXTURE THAN THE COMMON BRICK
Face bricks
Raw materials for building bricks:
Red burning clay
White burning clay
Budd burning clay
Manufacturing process for bricks:
Soft mud procedure
Stiff mud procedure
Dry process procedure
CONSIST OF MOLDING THE CLAY MIXTURE CONTAINING 20 TO 30 PERCENT WATER IN
MOLDS COATED WITH A THIN LAYER OF EITHER SAND OR WATER TO PREVENT STICKING
Soft-mud procedure
EMPLOYED FOR FIREBRICK AND IS THE ANCIENT METHOD FOR MAKING
BUILDING BRICKS
Soft-mud procedure
WATER CONTENT IS FROM 4 TO 7 PERCENT (USUALLY THE “AS-IS” CONDITION) WHICH
MAKES THE CLAY RELATIVELY NONPLASTIC
Dry process procedure
EMPLOYED FOR THE MANUFACTURE OF PRACTICALLY EVERY CLAY PRODUCT, INCLUDING ALL TYPES OF BRICK, SEWER PIPE, DRAIN TILE, HOLLOW TILE, FIREPROOFING, AND TERRA COTTA
Stiff-mud process
The great percentage of clay product is made from
Stiff-mud
Ways of drying bricks:
Outdoor
Shed
Tunnel drier
PROCESS OF REMOVING AIR FROM THE PUG MIL
De-airing
INCREASES THE WORKABILITY, PLASTICITY, AND’ STRENGTH OF THE UNDRIED BRICK BY REDUCING VOIDS, FOR ALL BUT A FEW CLAYS
De-airing
ARE USUALLY PLACED IN THE NEUTRAL GROUP
THOUGH THEY MAY BELONG IN BOTH ACID AND BASIC GROUPS DEPENDING ON THE RELATIVE SILICA-ALUMINA CONTENT
Fire-clay bricks
T&F. USUALLY ADVISABLE TO EMPLOY AN ACID BRICK IN CONTACT WITH AN ALKALINE PRODUCT OR VICE VERSA
F(inadvisable)
QUALITY OR DEGREE OF HAVING MINUTE SPACES OR HOLES THROUGH WHICH LIQUID OR AIR MAY PASS
Porosity
T&F. HIGHER THE POROSITY OF THE BRICK THE MORE EASILY IT IS PENETRATED BY MOLTEN FLUXES AND GASSES
T
T&F. LOWEST POROSITY HAVE THE GREATEST STRENGTH, THERMAL CONDUCTIVITY, AND HEAT CAPACITY
T
POINT WHERE THE MOLECULES HOLDING THEIR BONDS TOGETHER BREAK APART AND FORM A LIQUID
Fusion point
Fusion point can be determined by
Pyrometric cones
MEASURE HEAT-WORK, THE EFFECT OF TIME, AND TEMPERATURE
Pyrometric cone
FRACTURING OF A REFRACTORY BRICK OR BLOCK DUE TO UNEVEN HEAT STRESSES OR COMPRESSION CAUSED BY HEAT
Spalling
THE COMPRESSIVE OR FLEXURAL STRENGTH DETERMINED PRIOR TO FIRING
Cold strength
T&F. BRICKS WITH THE LOWEST THERMAL EXPANSION AND COARSEST TEXTURE ARE THE NOT RESISTANT TO RAPID THERMAL CHANGES AND DEVELOP LESS STRAIN
F(resistance)
T&F. DENSEST AND LEAST POROUS BRICKS HAVE THE HIGHEST THERMAL CONDUCTIVITY
T
Furnace heat capacity depends upod:
Thermal conductivity
Specific heat
Specific gravity
ONE OF THE MOST IMPORTANT FACTORS IS THE SIZE OF THE PARTICLES IN THE BATCH
Grinding
FUNCTION IS TO DISTRIBUTE THE PLASTIC MATERIALSO AS TO THOROUGHLY COAT THE NONPLASTIC CONSTITUENTS.
Mixing
PARTICULARLY SUITED FOR BATCHES THAT CONSISTS PRIMARILY OF NONPLASTIC MATERIALS
Dry-press method
USED TO REMOVE THE MOISTURE ADDED BEFORE MOLDING TO DEVELOP PLASTICITY
Drying
TWO IMPORTANT THINGS TAKE PLACE DURING BURNING:
Development of permanent bond
Development of stable minerals
Duringburning the volme may shrink as much as
30%
How many percent of refactory manufactor as nonbasic
95%
MOST WIDELY USED OF ALL AVAILABLE REFRACTORY MATERIALS, SINCE THEY ARE WELL SUITED FOR A VARIETY OF APPLICATIONS
Fireclay bricks
CONTAINS APPROXIMATELY 95 TO 96% SIO2 AND ABOUT 2% LIME ADDED DURING GRINDING TO FURNISH THE BOND
Silica bricks
UNDERGO PERMANENT EXPANSION
Silica bricks
MADE FROM MAGNESIA. CHROMITE. AND FORSTERITE
Basic refractories
FROM DOMESTIC MAGNESITES OR MAGNESIA
EXTRACTED FROM BRINES
Magnrsia refactories
2 type of insulating bricks
Backimg refactory brick
Regular refactiry brick
ALSO KNOWN AS “PORCELAIN ENAMEL” IS A SMOOTH, GLASSY, AND DURABLE SURFACE THAT IS FUSED AT TEMPERATURES HIGHER THAN 800 C
Vitreous enamel