Basic HTML Version
20
SECTION 1
polymers
polimeri
(to) manufacture
produrre/fabbricare
oxide
ossido
nitride
nitruro
carbide
carburo
TECHNICAL ENGLISH
10
On the basis of your knowledge of technology, list two different properties of each of the following
materials: copper, aluminium, zinc, brass, bronze, lead.
Always on the basis of what you have studied in technology, decide which metal you would use for each
of the following and give reasons for your choice by comparing the qualities of the materials you have
chosen.
electric cables bearings roof flashings cooking foil
11
Brainstorming
Look around your classroom and try to identify different types of materials the objects
in it are made of. Describe the material as it appears when you look at it and when you touch it. Use
adjectives such as:
soft
,
hard
,
rough
,
smooth
,
strong
,
light
,
heavy
,
fragile
,
natural
,
man-made
,
warm
,
cool
,
shiny
,
bright
,
dull
,
transparent
,
opaque
,
pleasant
,
unpleasant
,
springy
,
firm
,
powdery
,
slippery
etc.
12
Read the passage below and underline the key-words.
13
Now list the key-words that you have underlined and translate them.
TYPES OF MATERIALS
M
aterials are normally grouped together into types
based on what they were made from.
There are five main categories:
metals
,
polymers
,
ceramics
,
composites
,
wood
.
Recently, some new materials have been developed
with properties that can change with the environment.
Even though they have been given new names (for
example: smart materials), they still fall into one of the
first four categories.
Although, the materials in each category share certain
characteristics, there are often considerable differences
between the properties of individual materials even of
the same type.
Polymers
are the most widely used materials in
commercial production. These are organic materials
made up of a chain of single units called monomers.
They are
manufactured
by a process called
polymerisation. They can be synthetic, chemically
manufactured from carbon-based materials or natural,
made by processing natural elements, such as plants.
They include polypropylene, nylon and acrylic.
Ceramics are often
oxides
,
nitrides
, or
carbides
of
metals. They are used for a wide range of applications:
tools, insulators, lenses, plaster, bricks, etc. Most
ceramics are used in polycrystalline form.
TEXT 4
Plastic granules.
Progetto FOR MECHANICALS_unit_1.indd 20
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