Key points
- Material properties: materials have physical, aesthetic, and structural characteristics that guide their selection for specific applications
- Physical characteristics: these include density, hardness, thermal conductivity, and electrical conductivity, which determine how a material behaves under different conditions
- Aesthetic characteristics: these cover the appearance of materials, including colour, texture, and finish, affecting both visual appeal and sensory experience
- Structural characteristics: these relate to a material's ability to withstand forces, including strength, toughness, elasticity, and stiffness, determining its durability and performance
Introduction to Materials
A quick overview of woods, plastics and metals.
Knowing which material to use when designing or manufacturing a product is a very important skill to have. Different materials have a wide range of different properties. This means that choosing the correct material to use is a very important decision in the design and manufacturing process. In this video we will go over the most common material and their properties.
Wood can be split into 3 main categories. Hardwoods, softwoods and manufactured boards.
Hardwoods: These are generally a very hard and tough wood. They also give the best finish. However, they are more difficult to work with and can also be very expensive. Hardwoods come from deciduous trees and therefore take a long time to grow.
Softwoods:These are a much softer type of wood. They are however, much easier to cut and work with. They are also much cheaper than hardwoods. They are not as durable or long-lasting as hardwoods. Softwoods come from coniferous trees. They grow much faster than deciduous trees.
Manufactured Boards: These are man-made materials. Made using a number of different techniques. Each type of board for example plywood or chipboard are produced to have specific properties. They are also the cheapest type of wood to use. Manufactured boards do not give the nicest finish and will not last as long as the other two types.
Plastics are split into two categories, thermoplastics and thermosets.
Thermoplastics can be heated and shaped many times. Examples of thermoplastics are acrylic. This is used to make car headlights. It is often used as a glass alternative. Rigid polystyrene is another example. A common use of this would be for simple toys as it is hard while still being light.
As plastics can be moulded, a much more complex shape can be produced. Thermoset plastics can only be heated and shaped once. They are therefore more commonly found in instances where heat is more an issue. For example light fittings or a saucepan handle.
Metals are most commonly split into 3 categories ferrous, non-ferrous and alloys. Ferrous metals contain iron and therefore easily rust. They are also magnetic. Examples of these are iron and steel.
Non-Ferrous Metals do not contain iron, they therefore don't rust. They are also not magnetic. Some common examples are aluminium and copper. Lastly we have alloys. These are made up of a mixture of more than one metal. The most common examples of these are bronze (copper and tin) and brass (copper and zinc)
Material properties and characteristics can be broken down into three key categories physical, aesthetic and structural characteristics.
These characteristics guide designers and engineers in selecting the right material for a specific application.
What are physical characteristics of materials?
These refer to the measurable properties of a material, such as density, hardness, thermal conductivity and electrical conductivity.
Density is the amount of mass a material has for a given volume. It shows how heavy or light a material is compared to it's size.
Hardness is a measure of how resistant a material is to being scratched, dented or worn down. It indicates how tough the surface of the material is.
Thermal conductivity is how well a material transfers heat. A material with high thermal conductivity quickly moves heat through it, while one with low thermal conductivity resists heat flow.
Electrical conductivity is a material's ability to allow electric current to pass through it. A material with high electrical conductivity easily lets electricity flow, while one with low conductivity resists it.
What are the aesthetics of materials?
These describe the materials appearance and how it appeals to the senses. It includes colour, texture and finish.
Colour is the visual characteristic of a material determined by how it reflects or absorbs light. It affects the appearance of the material and can influence the aesthetic appeal and identification.
Texture describes the surface feel and appearance of a material, including whether it is smooth, rough, bumpy or glossy. It affects both how the material looks and how it feels to the touch.
Finish refers to the final surface treatment or coating applied to a material, affecting the appearance and feel. It can be glossy, matt, smooth or textured and influences durability, resistance to wear and overall look.
What are the physical characteristics of materials?
These relate to a material's ability to withstand forces, including strength, toughness, elasticity and stiffness.
Strength is a material's ability to withstand force without breaking or deforming. It indicates how much load a material can handle before it fails.
Toughness is a measure of how well a material can handle being hit or stressed without breaking. It means the material can absorb a lot of force and still stay intact.
Elasticity is a material's ability to return to its original shape after being stretched or compressed. It means that when you apply force, the material can change shape, but once the force is removed, it goes back to how it was before.
Stiffness is a measure of how much a material resists bending or stretching. A stiff material does not change shape easily when force is applied to it. It stays firm and rigid, making it less flexible.
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