III. Answer the following questions.
Date: 2015-10-07; view: 470.
II. Fill in the following table.
I. Copy the underlined words and word-combinations, translate them into Ukrainian and learn them.
Aluminium
Aluminium is lightweight, strong, and readily formable. Aluminium and its alloys, numbering in the hundreds, are available in all common commercial forms. Because of their high thermal conductivity, many aluminium alloys are used as electrical conductors.
Commercially pure aluminium has a tensile strength of about 13,000 psi. Cold-working the metal approximately doubles its strength. For greater strength aluminium is alloyed with other elements such as manganese, silicon, copper, magnesium or zinc. Some alloys are further strengthened and hardened by heat treatment. Most aluminium alloys lose strength at elevated temperatures, although some retainsignificant strength to 500o F.
| Materials | Qualities | |||||
| In English | In Ukrainian | Specific weight | Strength | Abundance | Melting point | Conductivity |
| Lithium Osmium Mercury Tungsten Aluminium Magnesium | __________ | 0.53g/cm3 22.5 g/cm3 - - + - | - - - - + - | most abundant | + + - - | - + - |
1. Which of the non-ferrous metals is the most abundant metal of earth?
2. Which is the most abundant metal of land?
3. What factors define the selection of materials?
4. Why is magnesium so expensive?
5. Name the properties of pure aluminium.
6. How are the properties of pure aluminium improved?
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