What Are Things Made From?
Everything around you — your desk, your phone, your clothes, the air you breathe — is made from materials. Scientists group materials by their properties, which helps us choose the right material for the right job.
A material is any substance from which objects can be made. Materials can be natural (found in nature) or synthetic (made by humans).
When you look around your classroom, you can spot many different materials: wood in the furniture, glass in the windows, metal in the door handle, plastic in your ruler, and fabric in your bag. Each was chosen because of what it can do.
Think of materials like ingredients in a recipe. A chef picks ingredients based on what each one adds to the dish. Engineers and designers pick materials based on what each one contributes to a product — strength, lightness, flexibility, and so on.
This unit is called Materials and Change — and that second word matters. As we explore what things are made from, keep asking yourself: can this material change? Can it be melted, bent, burned, or recycled into something new? We will return to this idea throughout the unit.
Major Groups of Materials
Scientists organise materials into broad groups based on shared properties. A widely used system in materials science groups them as follows:
- Metals — shiny, usually hard, good conductors of heat and electricity, often strong. Examples: iron, copper, aluminium, gold.
- Ceramics — hard, brittle, heat-resistant materials made from non-metallic minerals. Examples: glass, brick, porcelain, pottery.
- Polymers — materials made from long chains of molecules. Most plastics are synthetic (human-made) polymers, but natural polymers also exist (e.g., natural rubber, cotton, wool). Polymers are typically lightweight, mouldable, and often waterproof.
- Composites — materials made by combining two or more different materials to get the best properties of each. Example: fibreglass (glass fibres embedded in plastic resin).
- Other non-metallic materials — a broad category including wood, paper, and fabric, which come from living things.
These categories are not always perfectly separate — some materials could fit into more than one group, and scientists sometimes use different classification systems for different purposes. What matters is being able to describe the properties of a material and explain why it was chosen for a job.
Within metals, scientists make a further distinction: ferromagnetic metals (such as iron, steel, cobalt, and nickel) are attracted to magnets, while most other metals (aluminium, copper, zinc, brass) are not attracted to magnets.
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