Technology and market perspective for future Value Added Materials

Table 2: Classification of common engineering
materials
Group
Metals
and
Alloys
Ceramics
Organic
Polymers
Important characteristics
Hardness, resistance
to
corrosion, thermal
and electrical
conductivity,
malleability,
stiffness and
property of
magnetism.
Thermal resistance,
brittleness,
opaqueness
to light,
electrical insulation,
hightemperature
strength, abrasiveness,
resistance
to
corrosion.
Soft, light in
weight, dimensionally
unstable,
poor conductors
of heat and
electricity, ductile,
combustible,
low-thermal
resistance.
Source: Metallurgist Encyclopaedia.
Common examples
of engineering
use 33
Iron and steels,
aluminium, copper,
zinc, magnesium,
brass,
bronze, invar,
super alloys,
super-conductors,
etc.
Silica, glass,
cement, concrete,
refractories,
silicon carbide,
boron nitride
abrasives, ferrites,
insulators,
garnets, etc.
Plastics – poly
vinyl chloride,
poly tetra fluoroethylene,
polycarbonates.
Natural and
synthetic fibers –
nylon, terylene,
leather, etc.
Other uses –
explosives, refrigerants,
insulators,
lubricants, detergents,
fuels,
vitamins, medicines,
adhesives,
etc.
New additional classes for VAMs
Semiconductor materials are nominally
small band gap insulators. The defining
property of a semiconductor material is
that it can be doped with impurities that
alter its electronic properties in a controllable
way. The most commonly used semiconductor
materials are crystalline inorganic
solids. Semiconductors can be classified
into many groups following periodic
table groups of their constituent atoms 34
as well as by different approaches following
their general properties: e.g. elemental
semiconductors, compound semiconductors,
layered semiconductors, magnetic
semiconductors, organic semiconductors,
charge-transfer complexes and others.
Composite materials constitute the category
where most VAMs will be identified.
Composites are materials composed of two
or more distinct phases (matrix phase and
dispersed phase) and having bulk properties
significantly different from those of
any of the constituents. A composite therefore
is a combination of two or more
chemically distinct materials whose physical
characteristics are superior to its constituents
acting independently. The classification
of composite materials (based on
matrix material) follows this basic split: 35
Metal Matrix Composites (MMC) Metal
matrix composites are composed of
a metallic matrix (aluminium, magnesium,
iron, cobalt, copper) and a dispersed
ceramic (oxides, carbides) or
metallic (lead, tungsten, molybdenum)
phase.
Ceramic Matrix Composites (CMC)
Ceramic matrix composites are com-
33
Please note that these are not necessarily examples of VAMs, but
definitely there are VAMs existing within these groups in the form of
different composite materials.
24
34
See Fluck, E. ‘New notations in the periodic table’. Pure & App.
Chem. 1988, 60, 431-436; and Leigh, G. J. ‘Nomenclature of
Inorganic Chemistry: Recommendations.’ Blackwell Science, 1990.
35
Dr. Dmitri Kopeliovich, ‘Classification of composites’.
http://www.substech.com/