OXIDE AND NON OXIDE CERAMIC (Oxide ceramics (MAGNESIA (MgO) (Properties…
OXIDE AND NON OXIDE CERAMIC
Two most important magnesium materials are magnesite (MgCO3) and Brucite ( Mg(OH)2 )
1 . DEAD BURNING --- hydroxide or carbonate heated from 1500-2000 degree celcius.
2 . HARD BURNING --- hydroxide or carbonate is heated between 1000 to 1500 degree celcius to retain some of its chemical reactivity
3 . LIGHT BURNING --- temperature of heating is kept between 700 to 1000 degree Celcius and product resulting in more reactive
FUSION --- hydroxide or carbonate heated to temperature in excess of 2650 degree celcius . This process producing a very dense and inert product.
PH around 10.3
Transparency to infrared
High thermal conductivity
Good corrosion resistance
Low electrical conductivity
Types of Magnesia
Non Oxide ceramics
Titanium Boride (TiB)
good resistance to high temperatures
ood electrical conductivity
excellent resistance to oxidation.
chemically stable against numerous molten metals.
Solution phase reaction
- NaBH4 and TiCl4, followed by
the amorphous precursor obtained at 900–1100 °C
- a mixture of elemental Ti and B powders
Self-propagating high temperature synthesis process
- addition of varying amounts of NaCl.
- Self-propagating high temperature synthesis
- benzene of metallic sodium with amorphous boron powder and TiCl4 at 400 °C
Cathode material for aluminum smelting flux electrolysis
Sputtering target for hard material coatings
Crucibles for non-ferrous metals
Manufacture of cutting tools
synthesized by the carbonthermal reduction method using TiO2 (rutile), graphite and B2O3
Purity of (TIB)
98% in mass
crystal granularity is perfect
average particle size is 2-3 μm.