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7 Scan the table below to find materials which are:
| 1. soft 2. ductile 3. malleable 4. tough 5. scratch-resistant | 6. conductive and malleable 7. durable and hard 8. stiff and brittle 9. ductile and corrosion-resistant 10. heat-resistant and chemical-resistant |
| Materials | Properties | Uses |
| Metals | ||
| Aluminium | Light, soft, ductile, highly conductive, corrosion-resistant. | Aircraft, engine components, foil, cooking utensils |
| Copper | Very malleable, tough and ductile, highly conductive, corrosion-resistant. | Electric wiring, PCBs (printed circuit board), tubing |
| Brass (65% copper, 35% zinc) | Very corrosion-resistant. Casts well, easily machined. Can be work hardened. Good conductor. | Valves, taps, castings, ship fittings, electrical contacts |
| Mild steel (iron with 0.15% to 0..3% carbon) | High strength, ductile, tough, fairly malleable. Cannot be hardened and tempered. Low cost. Poor corrosion resistance. | General purpose |
| High carbon steel (iron with 0.7% to 1.4% carbon) | Hardest of the carbon steels but less ductile and malleable. Can be hardened and tempered. | Cutting tools such as drills, files, saws |
| Thermoplastics | ||
| ABS | High impact strength and toughness, scratch-resistant, light and durable. | Safety helmets, car components, telephones, kitchenware |
| Acrylic | Stiff, hard, very durable, clear, can be polished easily. Can be formed easily. | Aircraft canopies, baths, double glazing |
| Nylon | Hard, tough, wear-resistant, self-lubricatine. | Bearings, gears, casings for power tools |
| Thermosetting plastics | ||
| Epoxy resin | High strength when reinforced, good chemical and wear resistance. | Adhesives, encapsulation of electronic components |
| Polyester resin | Stiff, hard, brittle. Good chemical and heat resistance. | Moulding, boat and car bodies |
| Urea formaldehyde | Stiff, hard, strong, brittle, heat-resistant, and a good electrical insulator. | Electrical fittings, adhesives |
English for Electrical and Mechanical Engineering./ Er.H.GIendinning
8 Scan the table to find:
1 A metal used to make aircraft
2 Plastics used for adhesives
3 Steel which can be hardened
4 An alloy suitable for castings
5 A plastic with very low friction
6 A material suitable for safety helmets
7 A metal suitable for a salt-water environment
8 A metal for general construction use but which should be protected from corrosion
9 A plastic for car bodies
10 A metal used for the conductors in printed circuit boards
SPEAKING
9 What chemical objects are presented in the Figure below? Tell about these objects using the following phrases from the previous text.
| …can be divided into including The major markets for … are… to be used mainly in… to be principally used to make… to be used in markets ranging from… with applications including… | The principal raw materials for polymers are… to be primarily made from … to be usually produced with… to tend to have… to be generally characterized… to be sold for… |
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