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Metals Ceramics Plastics Glass Fibres EXAMPLES METALS IRON STEEL LEAD COPPER BRASS • MALLEABLE THEIR MAIN CHARACTERISTICS: • DUCTILE •HARD • USUALLY BURN ON HEATING • HIGH MELTING POINTS •STRONG •HIGH DENSITY •GOOD CONDUCTORS OF HEAT AND ELECTRICITY PLASTICS Typical properties: Examples: Flexible Low Density Easily Moulded Poor Conductors of Heat and Electricity Often Transparent Melt and often Burn on Heating POLYSTYRENE NYLON POLYETHANE TYPICAL PROPERTIES Hard Brittle Medium density very high melting points Non –conductors of heat and electricity Very unreactive Do not burn EXAMPLES China, Bricks, Tiles, Pots PROPERTIES Hard Brittle Medium density Very high melting points Non –conductors of heat and electricity Very unreactive Often Trasparent EXAMPLES Pyrex, Lead Crystal, Soft soda glass TYPICAL PROPERTIES : EXAMPLES Flexible Low density May burn on heating Long stringy strands Wool Paper Cotton Rayon Polyester APPEARANCE Shiny, ductile,malleable MELTING AND BOILING POINT Usually higher than non-metals HEAT CONDUCTIVITY Good conductors of heat SPECIFIC WEIGHT Heavier than non-metals CONDUCTORS OF ELECTRICITY Good conductors •Metals are used in everyday life and half of them are used for alloys with other metals. •Solidity and hardness are characteristics of metals,but mercury is liquid and both potassium and sodium are very soft. Lead is also soft and easily scratched. •Most metals are heavy but lithium is the lightest of all solids. •Gold,silver,platinum and mercury are known as precious materials. APPEARANCE MELTING AND BOILING POINTS Non-metals are dull. They are neither ductile, nor malleable. Usually lower than metals , many are gases HEAT Poor conductors of heat CONDUCTIVITY SPECIFIC WEIGHT Lighter than metals Poor conductors CONDUCTORS OF ELECTRICITY Composite materials are new types of products, made thanks to the flexibility of composite materials. Carbon fibres are very strong. They are used in many structural components ranging from propellers and rotor blades to body armour. 1) 2) 3) 4) 5) Iron is the second most abundant metal found in the earth’s crust. It is the most common and useful of all metals. It is silver grey , strongly magnetic , hard , malleable and ductile. Iron is only found in its pure form in meteorites, so it has to be extracted from various ores. The most common ones are magnetite and pyrite. Hardened steel Mild steel •Hard •Strong •Unmalleable •Softer •More malleable Cast Iron = smelting and carbon Heavy Brittle Zinc is a metal which cannot be found in nature as a pure metal. Its most common ores are zinc blend and calamine. The metal is used for roofing. It is also used to galvanise iron to prevent rusting. Zinc forms a large number of alloys. 1. 2. 3. 4. 5. Tin does not occur in a pure state in nature. The main source is the tinstone. Tin is a soft, malleable metal with a silverwhite lustre. Its main use is in the coating of steel to prevent rusting. Tinplate is also used in the canning industry. It Is a semiconductor. •flexible It is used in a variety of applications because it is •malleable •waterproof Solar panels Integrated circuits Silicon has a number of uses in Microprocessors Transistors Construction Industry The automotive Industry •Nitinol is a Smart Shape Memory Alloy. • Nitinol can be used for medical purposes. • It can also be used for the frames in your glasses.