Thermoplastic polymers These may repeatedly warmed and cooled
without appreciable changes occurring the properties the material. Alloy alloy mixture two more metals. Polyvinylchloride (PVC) used for cable insulation thermo-
plastic polymer. Let now define the terms and properties some the materials used
in the electrotechnical industry.
Synthetic rubber manufactured, opposed being produced natu-
rally.
Definition
Alloy alloy mixture two or
more metals. What makes them differ-
ent materials the way which the atoms and electrons are arranged and
how strongly the electrons are attracted the atoms.
Definition
Thermoplastic polymers These may be
repeatedly warmed and cooled with-
out appreciable changes occurring in
the properties the material.
Non-ferrous Metals which not contain iron are called non-ferrous. Plug tops, socket outlets and
switch plates are made from this material.
Definition
A conductor material, usually a
metal, which the electrons are
loosely bound the central nucleus.
An insulator material, usually non-metal, which the electrons are
very firmly bound the nucleus and, therefore, will not allow heat elec-
tricity pass through it.
Definition
Polyvinylchloride (PVC) used for cable
insulation thermoplastic polymer. They have
a flexible quality when operated maximum temperature 70°C but
should not flexed when the air temperature near 0°C, otherwise they
may crack.
Ferrous metals have magnetic properties. The word ‘ferrous’ comes from the Latin word ferrum meaning iron.
Definition
Corrosion The destruction metal
by chemical action.
Ferrous word used describe all metals which the main constituent
is iron. 4.
Definition
Ferrous word used describe all
metals which the main constituent
is iron. Copper, aluminium, tin, lead, zinc
and brass are examples non-ferrous metals. Brass alloy cop-
per and zinc, usually the ratio 70–30% 60–40%.
Rubber tough elastic substance made from the sap tropical plants.
Definition
Non-ferrous Metals which not con-
tain iron are called non-ferrous.
These electrons can easily become
‘free electrons’ which allows heat and
electricity pass easily through the
material. Most corrosion
takes place when metal contact with moisture (see also mild steel
and zinc). They
are non-magnetic and resist rusting.
Corrosion The destruction metal chemical action.
Thermosetting polymers Once heated and formed, products made from
thermosetting polymers are fixed rigidly. Synthetic artificial rubber carefully manufactured have all the
.
They are good insulators, but give off toxic fumes when burned.
All materials are made atoms and electrons.
Definition
An insulator material, usually a
non metal, which the electrons are
very firmly bound the nucleus and,
therefore, will not allow heat elec-
tricity pass through it. These electrons can easily become
‘free electrons’ which allows heat and electricity pass easily through the
material.
It good insulator, but degrades and becomes brittle when exposed to
sunlight. Cast iron, wrought iron and steel
are all ferrous metals.Basic Electrical Installation Work
100
Properties conductors and insulators
In Fig.
A conductor material, usually metal, which the electrons are
loosely bound the central nucleus.1 the last chapter looked the atomic structure materials
