Question

1. What are the main differences between alloys and composite materials? Explain with an example.

Answer 1

Both alloys and composites are a mixture of elements. The main difference between alloy and composite is their composition. An alloy has at least one metal in its composition while composites don’t have any metal components.

Alloy:

An alloy is a homogeneous substance that can be made by melting two or more elements, one of which is a metal. The participatory metal is classified as the parent metal, which acts as a base metal for the alloying material and the rest of the substances are called as alloying agents. The alloying agents can either be a nonmetal or metal in which their contribution or proportion is very small. Alloys have improved properties when compared to the properties of the constituent substance they are made of. Almost all the alloys are lustrous due to the presence of the metal component in their composition.

For an alloy: Material A + Material B -------> Material C

They mix each other to give an another material.

Examples of alloys are steel, brass, bronze, etc.

Composite:

Composites are also a mixture of two or more elements, but it does not contain metals in its composition. Unlike alloys, composites are heterogeneous. Most composites are found naturally while some are synthetic. Composites are made from components that have different physical properties.

For a composite Material: A + Material B ---------> Material A + Material B

Which means material A and B don't mix each other but they together. The constituents retain their identity that means they don't merge completely into one another, although they act in concert. We can distinguish the material A and B in the product.

A few of the examples of natural composites are wood, bones of the human body, etc. A few examples of synthetic composites are concrete, fiberglass, etc.

Difference Between an Alloy and a Composite:

Alloy	Composite
An Alloy is a mixture of one or more metals with other elements.	Composites are also a mixture of two or more elements, but it does not contain metals.
An alloy can either be a homogenous or a heterogeneous mixture.	A composite is always a heterogeneous mixture.
Alloys are lustrous due to the presence of metals in their composition.	Composites are not lustrous as they do not contain metals in their composition.
Most alloys can conduct electricity.	Composites do not conduct electricity except for polymeric composites.
Alloys always contain a metal.	Composites do not contain metals.

Alloys can be found naturally but they are rare. Composites occur naturally almost everywhere. The differences between alloy and composite should be understood clearly as they are closely related and are often used interchangeably.