Materials - Metals

Question 1

Aluminium Alloy

Answer 1

• Non-ferrous metal
• Silver white in color`

Question 2

Copper Alloy

Answer 2

• Non-ferrous metal
• Pinkish brown in color

Question 3

Silver

Answer 3

• Expensive, non-ferrous metal
• Bright silver in color

Question 4

Mild Steel

Answer 4

• Inexpensive ferrous metal
• Silver gray in color

Question 5

Carbon Steel

Answer 5

-Darker gray than mild steel due to carbon content

Question 6

Alloys

Answer 6

• Two or more metals melted then mixed together
• Ex: Iron + Carbon = Steel

Question 7

Alloy Examples

Answer 7

Aluminum Alloy - pure aluminum comes
from bauxite. Small amounts of copper,
magnesium and manganese are added

Copper - extracted from copper ore

Brass - an alloy of copper (65%)
and zinc (35%)

Silver - pure silver is very soft.
Sometimes 7.5% copper is added
to make it stronger (sterling silver)

Mild Steel - an alloy of iron with
0.15 to 0.35% carbon

Carbon Steel - an alloy of iron with
0.35 to 1.15% carbon added

Question 8

Common Metal Uses

Answer 8

Aluminum Alloy - used for car
engines and window frames

Copper - used for plumbing and
electrical wiring

Brass - used for locks and
water faucets

Silver - used for jewelry and
specialist electrical wiring

Mild Steel - used for car bodies
and major building structures

Carbon Steel - used mainly
for tools

Question 9

Workability of Common Metals

Answer 9

Aluminum Alloy - relatively soft, weak
metal but easy to work by hand (work
with hand tools) and easy to machine.

Copper - harder to work than aluminum
alloy but as easy to machine.

Brass - slightly easier than copper to
work by hand, the same to machine.

Silver - very easy to machine, slightly
more difficult to work by hand.

Mild Steel - easy to work by hand,
very easy to machine.

Carbon Steel - easy to work by hand because it has similar
properties to mild steel. It is not easy to machine because it can be
as hard as the cutting tools used in the machines.

Question 10

Densities of Common Metals

Answer 10

Silver - similar in hardness and
strength to copper but much denser

Mild Steel - quite hard and strong
metal, dense and difficult to stretch

Aluminum Alloy - it is one of the
lightest of metals (low density)

Copper - it is considerably denser
than aluminum alloy

Brass - brass is harder and
stronger than copper but is about
the same density

Carbon Steel - similar in strength
and density to mild steel