Alloys

What is an alloy?

A mixture of a metal with other elements (metals or non-metals) to improve its properties.

Why are alloys stronger than pure metals?

Different-sized atoms disrupt the metal’s regular structure making the layers distorted, making it harder for layers to slide over each other.

How do alloys compare to pure metals?

✅ Stronger and harder than pure metals.
✅ More resistant to corrosion in many cases.
✅ Designed for specific uses (e.g., lightweight, strong, corrosion-resistant).

What is steel?

An alloy of iron mixed with carbon and sometimes other metals (e.g., chromium, nickel).

uses of low carbon steel, high carbon steel and stainless steel

Type of Steel	Composition	Properties	Uses
Low-carbon steel	Iron + a small amount of carbon	Soft, easily shaped	Car body panels
High-carbon steel	Iron + more carbon	Hard, brittle	Cutting tools, bridges
Stainless steel	Iron + chromium + nickel	Corrosion-resistant, strong	Cutlery, surgical tools

What is bronze used for?

✅ Statues
✅ Medals
✅ Ship propellers

What is brass used for?

✅ Musical instruments
✅ Plumbing fittings
✅ Door handles

Why is gold alloyed?

Pure gold is too soft, so it is mixed with other metals to make it harder and more durable.

What is gold alloy used for?

✅ Jewellery
✅ Electrical components

How is the purity of gold measured?

In carats (e.g., 24-carat gold is 100% pure, 18-carat gold is 75% gold).

Why is aluminium alloyed?

Pure aluminium is soft, but alloys make it stronger while keeping it lightweight.

What are aluminium alloys used for?

✅ Aeroplanes (light but strong).
✅ Car bodies.

what is bronze an alloy of

copper and tin

what is brass an alloy of

copper and zinc