Manufactured board
Medium density fibreboard (MDF) is a manufactured board made from wood pulp which is bonded with a polymer called urea formaldehyde. The wood pulp is often made from the waste from cutting solid wood. Advantages of MDF · It is available in larger widths than solid wood. · Its properties can be uniform in different directions. · It is much cheaper than solid wood. Metals
Metal is made from metal ores, which have to be mined and processed to transform them into usable materials. It is rare for metals to be used in pure form. Normally they are mixed with other metals to improve their properties: the mixture is called an alloy. Most metals are good conductors. There are two main types of metal alloys: ferrous and non-ferrous. Ferrous metals contain iron. Non-ferrous metals do not contain iron. Both types of metals can be recycled.
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