Copper alloys

In addition to the extensive application of copper itself, it is largely used in the manufacture of alloys. Its alloys, especially those with zinc (the brasses) and with tin (the bronzes) are of vast importance for engineering and other purposes, while its alloys with other metals have numerous uses in many industries. When copper is cast in what is termed a closed mould - i. e., a mould with a small aperture or "ingate"- unsound vesicular castings only can be produced. To obtain a sound casting the mould must be an open one, hence none but articles of simple forms can be cast of the metal. This is why alloys of copper have come into such extensive use.

Copper alloys are the alloys based on copper. Here we can mention bronze, brass and also a copper-nickel alloys (for instance cupronickel) where nickel is a main alloying element. Bronze is an alloy of copper and tin, aluminum, beryllium or some other chemical elements which do not contain zinc or where it does not serve as a main alloying element. They distinguish a tin bronze, where tin is a main alloying element, and a tin less (special) bronze a tin less bronze may be double (with aluminum, beryllium, etc.) and multi-component.

Bronze has high anticorrosion properties and plasticity. Double bronze has an inclination for guttering effect and oxidation in molten condition. Such kind of bronze is difficult to solder. In order to improve the quality of such kind of bronze, it is alloyed with manganese, iron, nickel and some other elements. Abundance of bismuth, stibium, sulfur and arsenic (they form easily molten, fragile eutectics and lessen the strength of bronze) doesn't have to exceed the thousandth and the hundredth of a percent.

Brass is an alloy of copper and zinc contains 50% of Zn. Brass can be simple (consists only of copper and zinc) and multi-component (which consists not only of copper and zinc, but also of some other alloying elements, such as aluminum, manganese, nickel, tin, lead, flint). Brass has high anticorrosion properties in the air and in sea water. It oxidizes a little. Brass is widely used in shipbuilding, engineering industry, and instrument-making. It is used for manufacturing signs and decorations.

Cupronickel is an alloy of copper with nickel, iron, and manganese. It has high anticorrosion properties in sea and fresh water and it conducts electricity and heat very well. Cupronickel is used for manufacturing medical instruments, utensils, coins and decorations etc. Cupronickel got its name due to the surnames of French inventors. They were Majo and Sherrie who created this alloy in 1819.

Copper alloys are widely used in engineering industry, shipbuilding and aircraft building and also in electrotechical industry, and for manufacturing vapour-water accessories, utensils, etc. Cupronickel is used for manufacturing decorations, medical instruments, coins, etc.

Task 1

Read the following correctly:

the earth's crust, 0,0047%, cuprite, covellite, azurlite, bornite, affinage, 2541 degrees centigrade, halogens, blue vitriol, sulphuric acid, cuprous oxide, cupric oxide, charcoal, carbonaceous matters, an electrolyte anemia, lead, bismuth, to yield.

Task 2

Translate the following into English:

мінералоутворення, температура кипіння, галоген, купорос, деревинне вугілля, карбонатні речовини, піддавати електрохімічній очистці, спорідненість, боротьба з сільськогосподарськими шкідниками, недостатня кількість міді.

Task 3

Match the following word combinations with their translation. Fill in the table with the missing Ukrainian equivalents.

1. atomic weight 2. free state 3. industrial importance 4. chemical activity 5. blue vitriol 6. reducing agents 7. copper compounds 8. spinal fluid 9. sulphide solution	1-a	а) атомна вага b) c) d) відновлювач e) f) спінальна рідина g) h) i)

Task 4

Translate the names of the following elements into English and read it correctly:

натрій, галоген, кобальт, нікель, золото, срібло, цинк, свинець, вісмут.

Task 5	Fill in the gaps with the given verbs in proper tense form according to the meaning.
1. In the nature copper generally _____ as sulphide ore. 2. Natural copper _____ of two stable isotopes 63Cu (69.l%) and 65Cu (30,9%). 3. Copper _____ many alloys with different metals 4. Copper compounds _____ for manufacturing of catalysts, preparations for pest and fungi control, etc. 5. When heating, copper _____ with oxygen, sulphur, halogens, etc. 6. To obtain a very pure copper, it has to be _____ to electrochemical affinage.	a) to yield b) to form c) to react d) to consist e) to use g) to find

Task 6

Fill in the table according to the text “Copper and its importance”.

Points to be described	Detailed notes
Copper existence in nature.
Definition of mineral formation.
Main mineral formations.
Copper appearance.
List the properties of copper.
Two oxides of copper. List its properties.
Utilization of copper compounds.

Task 7

Give a short report on copper using the information from the table above.

Task 8

Match the following word combinations with their meanings (the text “Copper Alloys”):

1. unsound casting 2. sound casting 3. guttering effect 4. vapour-water accessories 5. copper alloys 6. molten condition 7. the extensive application 8. instrument-making industry 9. utensils

a. розплавлений стан b. широке застосування c. міцна, правильна виливка d. приладобудівна промисловість e. дефектна виливка f. пароводяні матеріали g. ефект витікання h. сплави міді i. кухонний посуд

Task 9	Scan the text “Copper alloys”. Fill in the table with the missing information.
Copper alloy	Alloy components	Alloy properties	Alloy applications
Bronze
Brass			- is widely used in shipbuilding, engineering industry, and instrument-making - is used for manufacturing signs and decorations
	- an alloy of copper with nickel, iron, and manganese.	- high anticorrosion properties in sea and fresh water - conducts electricity and heat very well

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