Tài liệu tiếng anh - LAMNGHIEPVN.INFO (Hưng Bùi) UNIT 2

UNIT 2: ENGINEERING MATERIALS
A. Reading:

Scanning tables

In engineering, it is important to practice reading tables, charts, diagrams, and
graphs because so much information is represented in these ways.
Scanning is the best strategy for finding information in a table. With scanning, you
know before you read what sort of information you are searching for. To scan a table, you
move your eyes up and down the columns until you find the word or words you want. To
scan quickly, you must learn to ignore any information which will not help you with your
task.
1. Scan the table which follows to find a material which is:
a. soft
b. ductile
c. malleable
d. tough
e. scratch-resistant
f. conductive and malleable
g. durable and hard
h. stiff and brittle
i. ductile and corrosion-resistant
j. heat-resistant and chemical-resistant
Materials
Metal
Aluminium
Copper

Properties

Uses

Light,
soft,
ductile,
highly Aircraft, engine components,
conductive, corrosion-resistant
foil, cooking utensils.
Very malleable, tough & ductile, Electric wiring, PCBs, tubing
highly
conductive,
corrosionresistant.

Brass (65% copper, Very corrosion-resistant. Casts well, Valves, taps, castings, ship
35% zinc)
easily machined. Can be work fittings, electrical contacts
hardened. Good conductor.
Mild steel (iron High strength, ductile, tough, fairly
with 0.15% to 0.3% malleable, cannot be hardened and General purpose
carbon)
tempered, low cost, poor corrosion
resistance
High carbon steel Hardest of the carbon steels but less Cutting tools such as drills,
(iron with 0.7% to ductile and malleable. Can be files, saws
1.4% carbon)
hardened and tempered.
Thermoplastics

High impact strength & toughness, Safety
helmets,
car

scratch-resistant, light & durable
components,
telephones,


ABS

kitchenware

Materials

Properties

Uses

Acrylic

Stiff, hard, very durable, clear, can Aircraft canopies, baths,
be polished easily, can be formed double glazing
easily

Nylon

Hard, tough, wear-resistant, self- Bearings, gears, castings
lubricating
for power tools

Thermosetting plastics
Epoxy resin

Polyester resin
Urea formaldehyde

High strength when reinforced, Adhesive, encapsulation of
good chemical & wear resistance
electronic components
Stiff, hard, brittle. Good chemical
and heat resistance
Moulding, boat and car
bodies
Stiff, hard, strong, brittle, heatresistant, and a good electrical Electrical fitting, adhesives
insulator

2. Scan the table to find:
a. A metal used to make aircraft.
b. Plastics used for adhesives
c. Steel which can be hardened
d. An alloy suitable for castings
e. A plastic with very low friction
f. A material suitable for safety helmets
g. A metal suitable for a salt-water environment
h. A metal for general construction use but which should be protected from
corrosion
i. A plastic for car bodies
j. The metal used for the conductors in printed circuit boards

B. Language study:

1. Making definitions

Study these facts from the table about aluminium:
1. Aluminium is a light metal.
2. Aluminium is used to make aircraft.


We can link these facts to make a definition of aluminium:
1+2 Aluminium is a light metal which is used to make aircraft.
We can use the relative pronoun which in making definition of something, and the
which-clause is known as the adjective clause in these cases.
Use the table above to make definitions of each of the materials in column A. Choose the
correct information in column B and C to describe the materials in column A.
A
1.
2.
3.
4.
5.
6.
7.
8.

an alloy
a thermoplastic
mild steel
a conductor
an insulator
high carbon steel
brass
a thermosetting plastic

B

a metal
a material
an alloy

a.
b.
c.
d.
e.
f.
g.
h.

C
allows heat or current to flow easily
remains rigid at high temperatures
does not allow heat or current to flow easily
contains iron & 0.7% to 1.4% carbon
becomes plastic when heated
contains iron & 0.15% to 0.3% carbon
formed by mixing other metals or elements
consists of copper and zinc

2. Adding information to a text
Study this sentence about aluminium
Aluminium is used to make aircraft, engine components, and many items for the
kitchen.
We can add extra information to the sentence like this:

Aluminium, which is light, soft, and ductile, is used to make aircraft, engine
components – for example, cylinder heads – and many items for the kitchen, such
as pots.
Note that the extra information is marked with commas or dashes:
, which …,
- for example, … , such as …,
Add this extra information to the following text about plastics.
1. plastics can be moulded into plates, car components, and medical aids.
2. Thermoplastics soften when heated again and again.
3. Thermosetting plastics set hard and do not alter if heated again.
4. ABS is used for safety helmets.
5. Nylon is self-lubricating.
6. Nylon is used for motorized drives in cameras.
7. Acrylic is a clear thermoplastic.
8. Acrylic is used for aircraft canopies and double glazing.


9. Polyester resin is used for boat and car bodies.
10. Polyester resin is hard and has good chemical and heat resistance.
Plastics are synthetic materials. They can be softened and moulded into useful
articles. They have many applications in engineering. There are two types of plastics:
thermoplastics and thermosetting plastics.
ABS is a thermoplastic which is tough and durable. Because it has high impact
strength, it has application where sudden loads may occur.
Nylons is a hard, tough thermoplastic. It is used where silent, low-friction operation
is required.
Acrylic can be formed in several ways. It is hard, durable, and has many uses.
Polyester resin is a thermosetting plastic used for castings. It has a number of useful
properties.

C. Word study:

Properties of materials

Study these examples of adjective and noun pairs for describing the properties of
materials.
Adjective

Noun

Flexible

flexibility

Light

lightness

Strong

strength

Now fill in the gaps in this table with the missing adjectives and nouns
Adjective
……….
elastic
……...
tough
soft
rigid

wear-resistant
………
hard

Noun
wind resistance
………
plasticity
……….
………
……….
………
brittleness
……….

New words and expressions:
-

ductile (adj.):
malleable (adj.):
scratch-resistant (adj.):
conductive (adj.):

dễ kéo sợi, dễ uốn
dễ dát mỏng
chống trầy xướt
có tính dẫn điện


-

-

durable (adj.):
stiff and brittle (adj.):
corrosion-resistant
(adj.):
friction (n.):
salt-water
environment:
circuit board:
alloy (n.):

bền
cứng và giòn, dễ gãy
chống ăn mòn (kim loại)
lực ma sát
môi trường nước mặn
bảng điện
hợp kim