30) Conversational topic “Materials Technology” should include:
• Material types;
Metals and non-metals
• metals- examples of metallic materials are iron (Fe) and copper (Cu)
• non-metals- examples of non-metallic materials are carbon (C) and silicon (Si).
As iron is such a widely used material, so that we can also divide into:
• ferrous metals - those that contain iron
• non-ferrous metals - those that do not contain iron.
• Elements, compounds and mixtures
With regard to the chemical composition of materials three main categories can be used:
• Elements are pure materials in their most basic form. They cannot be broken down into different constituents.For example iron, carbon and aluminium (AI).
• Compounds consist of two or more elements that are chemically bound - that is, combined by a chemical reaction. An everyday example is water, which is a compound of hydrogen and oxygen.
• Mixtures consist of two or more elements or compounds which are mixed together, but which are not chemically bound. For example alloys and etc.
•Composite materials
The earliest examples of composite materials were bricks made from mud and straw. A modern, everyday example is fibreglass- correctly called glass reinforced plastic (GRP) -which has a plastic matrix reinforced with glass fibres.
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