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Ceramics
Inorganic solids made up of metallic and nonmetallic or matalloid elements
ionic and covalent bonds
Crystalline or semi-crystalline structure
    Properties
  • heat-resistant
    high, well-defined melting points
  • Refractory (can withstand very high heat without deformation)
  • Poor conductors of thet and electricity
  • most ceramics have low densities
    • MgO·SiO2 Steatite 2.8
    • SiC Silicon Carbide 3.16
    • Si3N4 Silicon Nitride 3.3
    • AlN Aluminum Nitride 3.4
    • Al2O3 Alumina 3.8
    • Y2O3 Ittria 4.9
    • ZrO2 Zirconia 6.0
    • TiC·TiN Cermet 6.0
  • chemically inert
  • corrosion-resistant
  • hard
  • brittle
  • wear-resistant
  • may be opaque
    Categories of ceramics
  • Traditional
    • made of clay and cements
      that have been hardened by heating at high temperatures in special ovens called kilns
    • examples: dishes, crokery, flowerpots, roof and wall tiles
    • The earliest ceramic products were pottery made out of clay
  • Advanced
    • Carbides: SiC
      Oxides: Al2O3
      Nitrides: Si3N4
      many other materials: mixed oxide ceramics as semiconductors
    examples:
  • used as refractories in furnaces and durable building materials: bricks, tiles, cinder blocks
  • used as electrical and thermal insulators: spark plugs, telephone poles, electronic devices, and the nose cones of spacecraft
  • used as coatings on inexpensive materials that are resistant to cracks: in engines parts to reduce heat transfer
    Important types of pottery
  • earthenware (loza)
    • It is opaque
      non-vitreous (fired below 1200ºC)
    • glazed or unglazed
  • then stoneware (gres)
    • Vitrous or semi-vitreous
      nonporous
      glazed or unglazed
  • porcelain (porcelana)

Glasses
SiO2 is the main component of glass
It is a mixture of of two or more kinds of metallic silicates
Contain impurities that prevent crystallization
Amorphous structure (no long-range order)
    Properties:
  • soften over a range of temperatures
  • most glasses are translucent or transparent
  • hard
  • brittle
  • inert
  • biologically inactive

Glass ceramics
many tiny crystalline regions within a noncrystalline matrix
most glass-ceramics expand less than most glasses
examples: windows, wood stoves, radiant cooktop surfaces
    Glass-ceramics system
    A mix of oxides: Al2O3 × nSiO2
  • LAS system: x Li2O
  • MAS system: x MgO
  • ZAS system: x ZnO

Limestone Calcium Carbonate : Ca CO3
Quicklime Calcium oxide: Ca O
Hydrated or slaked lime Calcium hydroxide: Ca ( OH )2
Silica Silicon dioxide: Si O2
sand, flint, quartz,opal (hydrated)
Gypsum mineral :Calcium sulphate dihydrate: CaSO4·2H2O

Building materials * all building materials need water
Gypsum plaster or plaster Calcium sulphate hemihydrate : CaSO4 ·½H2O
other names: Plaster of Paris and calcined gypsum
Cement Portland cement: limestone + gypsum + clay or sand
Fibre cement Asbestos cement (in the past)
Mortar
  • Gypsum mortar: plaster + sand
  • Cement mortar:
    • Portland cement + sand
    • Pozzolana + sand
  • Lime mortar:
    • quicklime + sand
    • quicklime + cement mortar
Concrete Concrete: Cement + gravel (aggregate) = small stones + sand
    types of concrete:
  • mass concrete
  • structural concrete
      steel reinforced concrete
      • tensioned
        • pre-tensioned
        • post-tensioned

Ceramics
ceramics are earthy materials (from clay) made rigid by high temperature
  • porous:
    • clay
    • earthenware
  • waterproof:
    • stoneware
    • china (porcelain)
  • ceramics: They are in a crystalline state
    chemicals: Oxides, Carbides, Nitrides, sulphides.
  • glasses: They are in an amorphous state
    chemicals: Silica, Alumina; Calcium, Sodium, Boron, Magnesium, Lead oxides

Piedra caliza carbonato de calcio : Ca CO3
Cal viva Óxido de calcio: Ca O
Cal apagada Hidróxido de calcio: Ca ( OH )2
Sílice Dióxido de silicio: Si O2
arena, pedernal (sílex),cuarzo, ópalo (hidratado)
Yeso (mineral) mineral :Sulfato de calcio dihidratado: CaSO4·2H2O

Materiales de construcción * Todos ellos necesitan agua
Yeso Sulfato cálcico hemihidratado : CaSO4 ·½H2O
otros nombres: yeso cocido
Cemento Cemento Portland: Piedra caliza + yeso + arcilla o arena
Fibrocemento Cemento con amianto o asbesto (en el pasado)
Mortero
  • Mortero de yeso: yeso + arena
  • Mortero de cemento:
    • Cemento Portland + arena
    • Puzolana + arena
  • Mortero de cal:
    • cal viva + arena
    • cal viva + mortero de cemento
Hormigón Hormigón: Cemento + grava (áridos) + arena
    tipos de hormigón:
  • hormigón en masa
  • hormigón estructural
      hormigón armado (de barras de acero)
      • tensionado
        • pre-tensionado
        • post-tensionado

Cerámicos
Los materiales cerámicos son materiales terrosos (de arcilla) que se hacen rí,gidos por temperaturas altas
  • porosos:
    • arcillas cocidas
    • loza
  • impermeables:
    • gres
    • porcelana
  • cerámicos: Están en un estado cristalino
    composición química: Óxidos, Carburos, Nitruros, sulfuros.
  • vidrios: Están en un estado amorfo
    composición química: Sílice, Alúmina; Calcio, Sodio, Boro, Magnesio, Óxidos de plomo