Alloy steel is carbon steel that contains small amounts of other elements like manganese, silicon, nickel, and chromium added to improve properties. It has better tensile strength, hardness, toughness, and wear and heat resistance than carbon steel. Common alloying elements include chromium, cobalt, manganese, molybdenum, and nickel. Alloy steels are manufactured through processes of iron making, primary and secondary steelmaking, continuous casting, and forming to produce bars, wires, and other shapes for applications in automotive, engineering, construction, and other industries.

2.  Alloy steel- it is a steel that has small amounts of
one or more alloying elements (other than carbon)
such as manganese, silicon, nickel, titanium, copper,
chromium and aluminium added.
 It is alloyed with a variety of elements in total
amounts between 1.0% and 50% by weight to
modify or improve its mechanical properties

3. Alloy steel has some of its properties better
than carbon steel.
 Tensile strength
 Hardness
 Toughness
 Wear Resistance
 High Temperature Resistance

4.  Density (1000 kg/m3): Around 7.85
 Elastic Modulus (GPa): 190-210
 Poisson Ratio: Yield Strength (Mpa):366-1793
 Thermal Expansion (10-6/K): 9.0-15
 Melting Point (°C): 1371-1454
 Thermal Conductivity (W/m-K): 26-48.6
 Specific Heat (J/kg-K): 452-1499
 Electrical Resistivity (10-9W-m): 210-1251
 Tensile Strength (MPa): 758-1882
 Percent Elongation (%) : 4-31
 Hardness (Brinell 3000kg): 149-627

5.  Chromium – Adds hardness. Increased toughness and
wear resistance.
 Cobalt – Used in making cutting tools; improved Hot
Hardness (or Red Hardness).
 Manganese – Increases surface hardness. Improves
resistance to strain, hammering & shocks.
 Molybdenum – Increases strength. Improves
resistance to shock and heat.
 Nickel – Increases strength & toughness. Improves
corrosion resistance.
 Tungsten – Adds hardness and improves grain
structure. Provides improved heat resistance.

6.  Alloy steels are broken down into two groups: low-
alloy steels and high-alloy steels.
 low-alloy steels : increase strength and
hardenability.
 high-alloy steels : improves corrosion resistance
and stability at high or low temperature.
 Most commonly, the phrase "alloy steel" refers to
low- alloy steels.

7.  Simple alloy steel is alloy steel containing one
alloying element. for example, simple nickel
steel.
 Quaternary alloy steel is alloy steel that contains
two alloying elements, as, Chromium Vanadium
steel.
 Complex steel is alloy steel containing more than
two alloying elements such as high speed tool
steel.

8. This process can be divided into the following steps:-
 Iron making: In the first step, the raw inputs iron
ore, coke, and lime are melted in a blast furnace
.and turned into molten iron
 Primary Steelmaking: Primary steelmaking methods
differ between BOS and EAF methods. EAF method
feeds recycled steel scrap through use of high power
electric arcs (temperatures up to 1650 °C) to melt
the metal and convert it to high-quality steel.
 Secondary Steelmaking: Secondary steelmaking
involves treating the molten steel produced .This is
done by adding or removing certain elements
and/or manipulating the temperature and
production environment. the following secondary
steelmaking processes are be used:

9.  Vacuum degassing
 Continuous Casting: In this step, the molten steel is
cast into a cooled mold causing a thin steel shell to
solidify. The shell strand is withdrawn using guided
rolls and fully cooled and solidified. The strand is cut
into desired lengths depending on application.
 Primary Forming: The steel that is cast is then
formed into various shapes, often by hot rolling, a
process that eliminates cast defects and achieves
the required shape and surface quality. Hot rolled
products are divided into flat products, long
products, seamless tubes, and specialty products.
 Downstream processing - refers to recovery and
purification

10.  Alloy steels are manufactured in the form of:
Bars, Wires, Wire Rod, Bright Bars
 Sizes: Alloy steel products are manufactured in
size ranging from 5mm to 400mm width or
diameter.
 Shapes: Alloy Steel products are manufactured in
the following shapes -Square Round,Rectangle
,Hexagon Flat,Customized Shapes.

11.  Automotive- Transmission Parts, Engine Components, Steering
Components, High Tensile Fasteners, Fuel Injection Pumps,
Bearing Axles, Gears, Crankshaft, Transmission Chains, Springs,
Combustion chamber, Axles, Wheel Hubs
 Engineering -Cutting Tools, Structural Steel
 Industry- Mining Machinery, Energy exploration machinery,
food-processing units(non-corrosive environment)
 Construction- Reinforcing Bars Agriculture Tractor Parts
 Home -Utensils, Decorative purposes
 Railways- Wagon Axles, Crankshafts, Cushioning Device
Components, Steel Liners, Traction Gears
 Military- Ordnance, gun barrels, projectiles, missile
components

12.  The application of alloy steel is increasing everyday.
 Wide use in Automotive industries .
 Forging industry is the largest consumer of alloy
steel, which in turn caters to the need of automotive
and auto ancillary sector. The industry has registered
a growth of over 15% p.a. for the last two years.
 CARE(Credit Analysis & Research Limited) Research
expects the domestic alloy steel demand to grow at
a CAGR of 13.6% during the period FY11 to FY16.

13.  Wikipedia .org
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 www.intechopen.com