Smart materials

A smart material is when heat or electric applied which significantly changes its shape or colour.

Product	What smart material	What does the smart material do?	Properties + characteristics
Mug	Thermo chromic pigment	The smart material changes the colour or theme when it responds to heat, so when hot water is put into the mug, the warmth/humidity makes the mug change red to represent that it’s hot. If cold water is put in, it does the opposite and indicates the mug by showing a blue colour instead.	Changes colour due to heat.
Spoon	Shape memory alloys	Heat treatment gives the material memory of its original shape. When heat is applied to the spoon, it is able to bend the spoon. Once the spoon has been bended, you can get back it’s original shape by putting it under cold water and then straighten it using some force and it will return to it’s original shape.	Changes shape and can retain previous shape.
Warning signs	Phosphorescent pigments	The sign absorb light when it is out and when the lights are turned off, the light will emit after a certain amount of time.	Absorbs light then emits light.
Drawer	Smart grease	Controls the speed of the two materials that need to be required by absorbing the energy.	Control movement.

Composite materials

A composite material is more than one material which is combined together to make a property. They are usually different elements; physical and chemical properties that make up the composite material. 

Advantages

The advantages of using composite materials is that it is safe because fibres that are used to make the materials have a low electrical conductivity and are efficient fire retardants so that they don’t react as quick.

Composite materials have good strength because it is made up of multiple layers therefore it can withstand more pressure applied. They are made as strong as materials like aluminium and steel. They use a lot of fibres and fillers within each layer so that they reduce the impact done to the material.

Light weight- Composites are weighed less because they are made up of different thin layers. It is said they are 25% less than steel and 30% lighter than aluminium. Light composite are used for vehicles and aeroplanes. The Boeing 787 is a typical example which uses 50% composite materials for the weight of it.

Durable- It is very durable because it is made up from more than one layer that is stacked up upon each other. This is helpful as it makes products that use composite materials last longer.

Particle based composites

Tarmac –properties–used for Bike wheels, Cars wheels and road surfacing.-Characteristics – An Asphalt concrete, made up of multiple layers of minerals and asphalt, broken stone made with tar.

Concretes – properties – Buildings, bridges and paths. Characteristics – A solid material – very versatile – strength, durability and has a good thermal mass (Reduces the heat moving past the concrete.)

Cermets – properties Watches and circular power saw blades. – Cermets can be made out of ceramic and metal material. Characteristics-High temperature resistance and hardness, made out of ceramic and metal materials which are combined together.

Board composites

Hardboard - Used for clipboards, furniture and benches.

Chipboard- Used for flooring, furniture and wardrobes. 

Plywood -Used for seats, desks and housing e.g.: Ceiling.

Fibre composites

Natural wood – Used for toilet seats, drawers, for building support.

Elastomers mixed with fibre- Used for grip on shoes, tires, and springs on bicycles

Concretes mixed with fibres- Chair legs, basements and flooring.

How does the structure of plywood give material strength?

Plywood as a high density strength because it is a composite material made up by gluing woods that can be softwoods and hardwoods. The more layers and the more glue applied, the more strength Plywood will have as it will start to become more resistant if lots of different layers are being used.

MDF (Medium Density Fibreboard)

MDF is a wood product which is produced by the breaking down of softwoods and hardwoods into small fibres of wood. It is made up of all types of different fibre board. Sawdust can create MDF as when it is sawdust, it is all combined together with glue and then hardened to gives the physical properties of MDF. MDF can be used for worktops, draws and chairs.