1. ALLOYS AND PROPERTIES OF SOME COMMON ALLOYS
DEFINITION:
An alloy is a metal (parent metal) combined with other
substances (alloying agents),resulting in superior properties
such as; strength, hardness, durability, ductility, tensile
strength and toughness.
Example, mild steel is 0.1 - 0.3% Carbon and 99.9 - 99.7%
Iron.
Alloys are sometimes described as a mixture of two or more
metals. However, this is misleading, as often alloys are
composed of just one metal, as well as other non-metal
elements. Cast iron is an example, as it is a combination of
iron (metal) and carbon (non-metal).
.
2. Metal alloys have specific enhanced
properties compared to their ‘parent’ metals
• For example, steel. Steel is itself an alloy of iron and
carbon. Iron is a very brittle metal, likely to break or
snap if it receives a sudden blow/shock.
• Adding the alloying agent carbon, gives the new
property of toughness and tensile strength. Steel can
be used in the construction industry for bridges and
large buildings.
• A bridge manufactured only from the parent metal,
iron, would eventually collapse due to its inability to
absorb shocks/blows.
• The table below gives three alloying elements that can
be added to the alloy steel, to further improve its
physical properties.
3. Sr.NO Alloying Agent Properties Uses
1 CHROMIUM
Resists wear and increases
corrosion resistance. Increases
hardness and toughness
Stainless Steel
:Kitchen
utensils,
medical
instruments
2 VANADIUM Increased strength and
toughness of steel,
including wear resistance
Crank shafts
,some hand
tools. surgical
instruments
3 NICKLE Increased strength and
hardness, resistance to
corrosion.
Engine parts,
turbine blades
measuring
tabes
4. • Properties of Brass
Brass is a metal made of copper and zinc, having a muted yellow color,
somewhat similar to gold.
• Brass Properties
Some of the useful properties of brass include:
Relatively resistant to tarnishing
Good malleability
Good acoustic properties
Decorative golden color
Relatively low melting point and flow characteristics make it a relatively
easy to cast
Nonmagnetic
Low coefficient of friction
• Applications of Brass
Brass is often used for: Musical instruments, Lamps, Knobs, Handles,
Bowls, Bearings, Sleeves, Bushings, Nuts and bolts, Gears, Valves,
Plumbing, Electrical devices, Bells, Hinges, Clock hands, Gibs, Slides,
Machine tool components and Zippers.
5. • Properties and Uses of Bronze
• Bronze is a metal alloy consisting primarily of copper and
other metals with tin as the main additive. It is an
extremely malleable and durable alloy, and can last for
years. Bronze is less brittle than other metals, like iron and
steel.
• Bronze is also tremendously weather-resistant and does
not rust when exposed to moisture. It is often used in
modern architecture, especially for railings and grills, which
gives many public buildings an air of grandeur and charm.
Bronze is also the alloy of choice in the casting of public,
outdoor statues. Its malleability makes it ideal for pouring
into elaborate moulds and has a distinguished aesthetic
finish.
• Other variations of bronze are common in other industries:
alpha bronze, which is commonly used in the manufacture
of coins, fine blades and turbines; and bismuth bronze,
used in light reflectors and mirrors.
