Match the same words with the antonyms (text A)

1) realized 5) low a) stop e) high

2) continue 6) superior b) unrealized f) usual

3) use 7) widespread c) conserve g) unknown

4) emerge 8) major d) vanish h) secondary

13. Translate the text on theory and practical use of PVD coatings, study the structure of TiALN. Make its technical and non-technical description.

Hard materials suitable for thin films are predominantly but not entirely carbides, nitrides, borides and silicides. It is also groups of metals from the periodic table. The first generation of hard PVD coatings were single metal nitrides such as TiN, CrN, and ZrN. They have been exploited commercially because of their higher hardness compared to high-speed steel and cemented carbide and for decorative purposes. ZrCN for example is used to simulate gold in decorative applications such as watch cases. Alloyed elements are known to improve oxidation resistance, e.g. TiALN. This improvement in temperature resistance was achieved by introducing other elements such as Cr, Al or Y, into the TiN lattice. PVD coating development continued through deposition of multi- layers and super-lattices. At present, scientists study nano-composite coatings.

Artist’s impression of the structure of TiALCN

14. Scan the text about Copper (Cu) carefully. Use the scattered Nouns – Verbs – Adjectives – Adverbial Modifiers to make as many correct sentences-statements as possible.

Copper is a highly malleable (i.e. easily worked), red-brown metal, which is ductile and has many uses. It occurs as native copper and in a variety of mineral forms. Copper is extracted by smelting and refining by electrolysis. Copper has been an important metal for thousands of years in its alloys, brass and bronze. It is used in coins as an alloy with nickel. Since copper is an excellent conductor of electricity, it is widely used in the electrical industry. It is also used as pipes for plumbing, in paints, pigments, printing and fungicides (chemical solutions, which destroy fungal growth.

Copper:

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