1.8 - Alloys

yes. i know this is technically 1.7 also. let me have this

What are alloys?

a mixture of a metal with at least one other element (this can be another metal or a non metal)

Why are alloys harder than pure metals?

• by mixing two or more metals together, the regular arrangement of the atoms is disrupted (alloy formed)

• this larger/smaller element prevents the original metal ions forming layers and the ions cannot slide past each other any longer

Why are alloys used?

pure metals don’t always have the properties needed

What are some examples of alloys?

• steel

• magnalium

• nitinol

How are steels made?

by adding small amounts of carbon to the pure iron

What is a benefit of steel?

• iron will rust fairly quickly, but steel is much less likely to rust

• steel is a lot stronger than iron

What is magnalium?

an aluminnum alloy containing 5% magnesium

What are the benefits of magnalium?

is stronger, lighter and more resistant to corrorosion than aluminum

What are aluminum alloys used for?

aircrafts, car parts, soda cans and aluminum foil

What is a shape memory alloy?

an alloy that "remembers" its original, cold-forged shape: returning to the pre-deformed shape when heated

What is nitinol?

a shape memory alloy of nickel and titanium

What are the uses of shape memory alloys?

• glasses frames

• triggers to start the sprinklers in fire alarm system

• controllers for hot water valves in showers or coffee machines