Metals

Question 1

Ferrous metal

Answer 1

• contains ferrite/iron, so will oxidise (rust)
• almost all are magnetic
• produced in blast furnaces
• carbon added to produce different grades of metal

Question 2

Ferrous metal examples

Answer 2

mild steel
iron
cast iron
high speed steel
pyrite
stainless steel

Question 3

Alloys

Answer 3

• all metals are found in the form of oxides or sulphates, extracted from ore before any useful processing.
• metals that are formed by mixing two or more metals, to improve their properties.
• grouped into ferrous and non ferrous alloys.

Question 4

Non ferrous metal examples

Answer 4

aluminium
copper
silver
gold
brass
mercury
zinc
gallium
tin
titanium
nickel
cobalt
magnesium
lead
pewter

Question 5

Non ferrous metal

Answer 5

• contains no iron
• mainly produced by electrolysis
• expensive production due to electrical energy costs involved

Question 6

micro structure

Answer 6

• metals are made of crystalline structures
• 3 forms of regular lattice patterns:
  close packed hexagonal
  body centred cubic
  face centred cubic

Question 7

close packed hexagonal

Answer 7

zinc, magnesium
- weak, poor strength to weight ratio

Question 8

face centred cubic

Answer 8

aluminium, copper, gold, silver, lead
- very ductile, good electrical conductors

Question 9

body centred cubic

Answer 9

chromium, tungsten
- hard, tough

Question 10

types of metal manufacturing

Answer 10

press formed
extrusion
die cast
sand casting

Question 11

press formed

Answer 11

cold sheet
male+female mould
quick and efficient

Question 12

extrusion

Answer 12

profiling one pattern through a die, then cooled

Question 13

die cast

Answer 13

lots of detail
moulded (expensive to make the mould)
molten metal poured
lots can be produced

Question 14

sand casting

Answer 14

not perfect, not much detail
quick, efficient
can cast a range of sizes (post-box)
cost effective but you have to finish the piece