Metals

Question 1

what does conductivity mean?

Answer 1

Ability for electricity to pass through

Question 2

what is malleability

Answer 2

the ability of a material to deform by bending, twisting or stretching; ability to be drawn out without breaking. It increases with temperature

Question 3

what is hardness

Answer 3

Is the ability of a material to resist wear, scratching and indentation

Question 4

toughness

Answer 4

The ability of a material to withstand blows or sudden shocks without breaking

Question 5

ductility

Answer 5

Ability of a material to be permanently deformed in all directions without fracture. It increases with temperature

Question 6

What are the 2 different types of metals

Answer 6

Ferrous and non-ferrous

Question 7

What is a ferrous metal

Answer 7

a metal that contains iron and t=so therefore are magnetic

Question 8

what is a non-ferrous metal

Answer 8

a metal not containing with iron, often pure metals

Question 9

name 3 ferrous metals

Answer 9

tungsten steel
high carbon steel
cast iron

Question 10

name 3 non-ferrous metals

Answer 10

tin
titanium
copper

Question 11

name the 6 manufacturing processes

Answer 11

Sand casting
extrusion
die casting
welding
forging
hardening, tempering and annealing

Question 12

name the 4 stock forms

Answer 12

bar, sheet, plate, pipe

Question 13

How do you extract metals from their ore

Answer 13

furnace heating- the ore is heated to such a high temperature( above the metals melting point) that the metal separates from the other substances in the ore.

Question 14

where can you find metals

Answer 14

in ores within the earths crust

Question 15

What is sand casting

Answer 15

Sand casting is another way of creating metal products using a mould. A pattern shape of the product to be manufactured is made in sand. Molten metal is then poured in and allowed to cool before being removed from the sand. Sand casting is one of the oldest forms of metal casting.

Question 16

What is annealing?

Answer 16

this is heating a metal to a specific temperature and then allowing it to cool slowly.It is often used to make metal more malleable and ductile tobe worked on. it can be carried out repeatedly.

Question 17

Name the different head shapes for the machine screws

Answer 17

Slotted
Pozidriv
Phillips
Allen

Question 18

what is the difference between a nut and a bolt

Answer 18

nut= metal fastener with a threaded hole
bolt= is a type of screw that fits the thread in the nut

Question 19

what are nuts and bolts used for and what are they made from

Answer 19

they are used to join metal, wood and plastic together. they are usually made of carbon steel but some a coated with zinc to make them resistant to corrosion - usually when being used outdoors.

Question 20

what needs to be done to a metal before it can be treated

Answer 20

it needs to be smoothed and cleaned with abrasives (e.g metal wool) and chemical cleaners (e.g degrease)

Question 21

what is dip coating

Answer 21

This is the process of covering a metal with plastic. The metal is heated to between 180°-1200°C and then dipped into fluidised plastic powder. this is powder that has air blown through to make it act like liquid. The coated metal is returned to the oven where the plastic melts and gives a smooth finish.. This is used to cover tool handles and wheelchair parts.

Question 22

what is powder coating

Answer 22

This is spraying a plastic powder onto a metal part and heating it to fuse the powder to the metal. The powder is sprayed onto the metal with an electrostatic gun which gives it an electrical charge and makes it attracted to the metal. This is commonly used for bike frames, wheels and outdoor play equipment.

Question 23

Galvanising

Answer 23

This is used to protect a base metal like iron or steel from corrosion.This is done by coating the base metal with a more reactive metal, such as zinc. The zinc creates a barrier and protects the base metal from corrosion. However, if it is scratched or damaged, the base metal can be exposed. Gates and metal pails are often galvanised.

Question 24

name the properties and composition of mild steel

Answer 24

ductile, tough, easy to shape, good conductor
This is an alloy of iron containing carbon and some other metals-used on car bodies and nuts/bolts

Question 25

name the properties and composition of stainless steel

Answer 25

doesn’t rust, easy to clean, hard, smooth
alloy of iron and chromium (from 10.57 to 27%). The chromium produces an oxide layer to prevent corrosion. used for kitchen utensils

Question 26

name composition and uses of cast iron

Answer 26

2.5-4% carbon
1-3%silicon
remainder is iron

brake discs, manhole covers, large casting

Question 27

name properties and composition of aluminum

Answer 27

soft and malleable, excellent

Question 28

what is a scale layer?

Answer 28

Oxidized layer that forms during heating and forging of steel

Question 29

How do you die cast?

Answer 29

1. Mold design- create a mold called a die. Usually made from steel or aluminum. Develop a CAD design and create with a CNC machine
2. Metal is melted in a furnace and poured into a ladle
3. Injection- once the metal is liquidized, it is injected into the mold under high pressure. Once collide and is taken out and trimmed
4. finishing is applied