Metals

Question 1

What are the two types of metal?

Answer 1

• Ferrous
• Non-Ferrous

Question 2

What is a ferrous metal?

Answer 2

• Metals that contain Iron
• They corrode quickly and easily
• Are magnetic due to iron content

Question 3

What is a non-ferrous metal?

Answer 3

• Metals that don’t contain iron
• More resistant to corrosion
• Better electrical conductors
• More expensive than ferrous

Question 4

What are some common shapes in which metals are available?

Answer 4

• Round bar
• Box section
• Tube
• Sheet
• RSJs

Question 5

Examples of ferrous metals

Answer 5

• Mild steel
• Carbon Steel
• Stainless steel
• Cast iron
• Wrought iron

Question 6

Examples of non-ferrous metals

Answer 6

• Aluminium
• copper
• tin

Question 7

Properties of metals

Answer 7

• High melting point
• High tensile strength
• Shiny finish
• Malleable
• ductile
• Good conductor

Question 8

Mild steel

Answer 8

• Inexpensive
• Tough
• Easy to work
• 99.95% Carbon approx.
  e.g. Building and car bodies

Question 9

Medium carbon steel

Answer 9

• Similar to mild steel
• Slightly harder and less ductile
• 99.7% Iron
  e.g. Axels and Crank shafts

Question 10

High Carbon Steel

Answer 10

• Harder and stronger than mild steel
• More brittle
• 99.4% Iron
  e.g. High strength cables and springs

Question 11

Tool steel

Answer 11

• Extremely hard
• Resistant to heat
• 98.5% Iron
  e.g. Cutting tools and machines

Question 12

Stainless Steel

Answer 12

• Resistant to wear and corrosion
• Iron, Nickel and minimum of 10.6% Chromium
  e.g. Cutlery and utensils

Question 13

Cast Iron

Answer 13

• High Compressive Strength
• Extremely Brittle
• Extremely Resistant to corrosion
• up to 6% carbon and 94% iron
  e.g. Saucepans and engine block

Question 14

Wrought Iron

Answer 14

• Strong
• High resistance to corrosion
• Attractive patina as it ages
• Almost 100% iron
  e.g. Ornamental gates and fences

Question 15

Features of Non-Ferrous Metals

Answer 15

• Over fifty non-ferrous
• Don’t corrode as fast
• Most commonly used:
  
  • Aluminium
  • Copper
  • Lead
  • Zinc
  • Tin

Question 16

Aluminium

Answer 16

• Lightweight
• Malleable
• Polishable to mirror
• Good conductor
  e.g. Drinks cans and plane parts

Question 17

Copper

Answer 17

• Soft and very ductile
• Malleable
• Verry good conductor
• Good corrosion resistance
  e.g. Jewellery and Electric cables

Question 18

Lead

Answer 18

• Soft and malleable
• Dense
• Resistant to corrosion
• very Resistant to acid
  e.g. Car batteries and weights

Question 19

Zinc

Answer 19

• Weak
• Brittle
• Poor conductor
• Extremely resistant to corrosion
• Retains shiny finish
  e.g. Coating on ferrous metals

Question 20

Tin

Answer 20

• Ductile
• Malleable
• Very resistant to corrosion
  e.g. Corrosion prevention layer on other metals

Question 21

Brass

Answer 21

• Copper and zinc alloy
• Durable
• Corrosion resistant
  e.g. Trumpets and fittings

Question 22

Pewter

Answer 22

• Tin, copper, lead and antimony alloy
• Tough
• Malleable
• Polishes well
  e.g. Tankards and cheap jewellery

Question 23

Duralumin

Answer 23

• Aluminium, copper, manganese and magnesium alloy
• Lightweight but very strong
• Expensive and hard to extract
  e.g. Aircraft and car chassis

Question 24

Solder

Answer 24

• Lead and Tin alloy (old)
• Tin and copper alloy (modern)
• Malleable
• Low melting point
• Good conductor
  e.g. Electrical and plumbing connections

Question 25

Alnico

Answer 25

- Iron, nickel, Aluminium and Cobalt Alloy - Very Magnetic - Good conductivity - Corrosion resistant e.g. Loudspeaker magnets

Question 26

Bronze

Answer 26

- Copper and tin alloy with others - Malleable - Ductile - Good conductor - Attractive color e.g. Sculptures and instruments

Question 27

Gunmetal

Answer 27

- Copper, zinc and tin alloy - Tough - Durable - Low friction e.g. Valves and hydraulic equipment

Question 28

Stering Silver

Answer 28

- Silver and Copper alloy - Shiny and attractive - Ductile - Very soft - tarnishes easily e.g. Hugh quality cutlery