Building Materials, Third Edition

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resists alkaline corrosion, but gets readily dissolved in nitric acid and aquaregia. The presence
of carbon, arsenic, sulphur leads to brittleness. Small amounts of magnesium render it more
ductile whereas iron makes it hard.

…Nickel is used in making nickel steels, coin, German silver, wires, as catalyst and for
moisture-proof packings. Nickel is widely used as an alloying element in steel and cast iron
and as an electro-deposited coating over steel to give corrosion protection. Nickel is also used
to form alloys with such elements as copper, chromium and iron.

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The various alloys of nickel are designed to have certain characteristics such as a high degree
of toughness, corrosin resistance, oxidation resistance, low creep rate at high temperatures,
and good properties at very low temperatures. Some of the important nickel alloys are as
follows:

w2w— is made by alloying copper with nickel. These are used where high strength,
pressure tightness, high resistance to corrosion and wear is required. They are widely used in
marine, chemical, power, electrical, and oil-refinery equipments.

r2e are alloys consisting principally of nickel, molybdenum, and iron. These are
resistant to a wide variety of non-oxidizing acids and salts.

s™ consist principally of nickel, chromium, and iron. These have high resistance to corrosion
and to oxidation at high temperatures.

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1. Describe manufacture, properties and uses of:
   (a) Copper (b) Aluminium (c) Lead


2. Give the properties and uses of following:
   (a) Tin (b) Nickel (c) Zinc


3. Describe the extraction, properties and uses of any three non-ferrous metals. Describe also
   their alloys and uses.


4. Discuss the use of non-ferrous metals as building materials.


5. What is the difference between ferrous and non-ferrous metals? Give two examples of each
   type and state their properties and uses.


6. Write notes on:
   (a) Brazing (b) Soldering (c) Annealing


7. What is an alloy? Describe the properties and uses of brass and bronze.


8. Describe the following:
   (a) Gun metal (b) Monel metal (c) White metal
   (d) Yellow metal (e) German silver (f) Pewter