Metals

Question 1

What are the three main Categories that metals are classified into ?

Answer 1

• ferrous
• non- ferrous
• alloys

Question 2

What are the advantages of joining metals together ?

Answer 2

In comparison to pure metals, they have better corrosion resistance, lower costs, higher strength and better workability

Question 3

Where is metal sourced from ?

Answer 3

They are often sourced from mines in the form of ores.

Question 4

What is used to increase the hardness of iron ?

Answer 4

Carbon is a common additive used to increase the hardness

Question 5

What do all ferrous metals contain ?

Answer 5

Iron (Fe)

Question 6

What are ferrous metals ?

Answer 6

Metals that contain iron , are magnetic and can rust

Question 7

What are non ferrous metals ?

Answer 7

Metals that do not contain iron , aren’t magnetic and can’t rust

Question 8

What is an alloy ?

Answer 8

It is a combination of two or more metals, or two or more elements , one of which must be a metal

Question 9

Properties of low carbon steel ?

Answer 9

• malleable
• ductile
• relatively inexpensive in comparison to other metals
• has a good tensile strength however it is lower than higher carbon steel
  -easy to weld

Question 10

What type of metal is low carbon steel ?

Answer 10

Ferrous metal

Question 11

What are the applications of low carbon steel ?

Answer 11

• nuts / bolts
• automotive parts

Question 12

Why is low carbon steel used in refrigerator panels ?

Answer 12

-relatively cheap
- hard
- easy to form - press former
- easy to weld

Question 13

What are the properties of medium carbon steel ?

Answer 13

-less ductile than low carbon steel
- hard
- malleable
- tough
- good tensile strength

Question 14

What are the applications of medium carbon steel ?

Answer 14

Applications include gears , springs , rail tracks and machine parts

Question 15

What properties make it suitable for medium carbon steel to be used for gears ?

Answer 15

They have a good wear resistance , can be hardened , widely available and are relatively inexpensive.

Question 16

What are the properties of grey cast iron ?

Answer 16

-distributes heat evenly
- withstands compression resisting deformation
- very hard
- good resistance to oxidation
- can be brittle and has a low impact resistance

Question 17

What are the applications of grey cast iron ?

Answer 17

• radiators
• cookware
• stoves

Question 18

What are the properties of white cast iron ?

Answer 18

• excellent resistance to abrasion
• greater tensile strength than grey cast iron
• hard and brittle
• can be cast with little shrinkage

Question 19

What are applications of white cast iron ?

Answer 19

Applications include extrusion nozzles , dies , stone crushers and industrial rollers

Question 20

What are the stock forms that metals can come in ?

Answer 20

• sheets varying thicknesses of 1mm to 3mm
• plates , generally thicker than 3mm and narrower
• bars
• tubes , hollow cross sectional
• structural angular shapes such as H beams , L beams ..

Question 21

How is metals extracted ?

Answer 21

The raw metal is extracted from the ore through a combination of crushing, smelting or heating , with additional chemicals and huge amounts of energy