Alloys Flashcards

All 6 cards in this deck

What is an alloy?

A mixture of a metal with one or more other elements.

Using a model of layers of atoms, why is an alloy usually stronger and harder than the pure metal?

e.g. brass compared with pure copper

The alloy contains atoms of different sizes, which disrupt the layers so they cannot easily slide over each other; zinc atoms are larger than copper atoms, so brass is harder than pure copper.

True or false? In a pure metal the layers of atoms can easily slide over each other.

True. All the atoms are the same size, so the regular layers slip easily, making pure metals softer.

True or false? An alloy is a compound formed when two metals react together.

False. An alloy is a mixture, not a compound.

Why is iron alloyed with other metals to make alloy steels?

Pure iron is too soft and corrodes easily; alloy steels are harder, stronger and can be made more resistant to corrosion.

Which metal is added to iron to make stainless steel, and what is stainless steel used for?

Chromium (often with nickel); it resists corrosion, so it is used for cutlery, sinks and chemical plant.