• Mild steel is a type of carbon steel with a low amount of carbon – it is
actually also known as “low carbon steel.”
• The amount of carbon in mild steel is 0.05% to 0.25% by weight, whereas
higher carbon steels are typically described as having a carbon content
from 0.30% to 2.0%.
• Less carbon means that mild steel is more ductile, machinable, and weld
able than high carbon and other steels.
• Mild steel also has a high amount iron and ferrite, making it magnetic
• less tensile strength than high carbon and alloy steels
The process of heat treatment is carried out first by heating the material and then
cooling it in the brine, water and oil. The purpose of heat treatment is to soften the
metal, to change the grain size, to modify the structure of the material and to
relieve the stress set up in the material after hot and cold working.
Manufacturing of mild steel
•Direct-reduced iron (DRI), also called sponge iron , is produced from
the direct reduction of iron ore (in the form of lumps, pellets, or fines) to
iron by a reducing gas or elementary carbon produced from natural
gas or coal.
•A blast furnace is a type of metallurgical furnace used for smelting to
produce industrial metals and its alloys, generally iron, but also others
such as lead or copper
•An electric arc furnace (EAF) is a furnace that heats charged material by
means of an electric arc. while blast furnaces cannot vary their
production by much and can remain in operation for years at a time,
EAFs can be rapidly started and stopped, allowing the steel mill to vary
production according to demand.
Steel can be recycled over and over again without losing any of its
properties. An interesting fact is that recycling 1 t of steel helps to
save 1.8 barrels of oil, 10.9 million Btu's of energy, 642 kWh of
energy, and 2.3 m3 of landfill space.
Steel recycling can be performed by following some of these steps:
Sorting – Magnets can be used to attract the steel away from other
materials in a recycling facility
Shredding - Shredders are designed with rotating magnetic drums
that extract iron and steel from other metals and materials
Media separation- by using electrical currents, high-pressure air flows
and liquid floating systems, further separation of steel from other
materials can be achieved
Shearing - Hydraulic machinery are used to cut thick heavy steel
recovered from railways and ships by exerting enormous pressure on
the items. Sometimes gas and plasma arch are used
Steel is then melted and reshaped before being used in the
production of a variety of commodities ranging from bikes and new
cans to paper clips.
PROPERTIES OF MILD STEEL
• Ductile & malleable
• More tough and more elastic than cast iron and wrought iron
• More prone to rusting than wrought iron
• Corrodes quickly
• Easily forged, welded & riveted
• Withstands shocks & impacts well
• Not much affected by saline water
• Equally strong in tension, compression and in shear
• Difficult to harden and temper
• density7.8 gm/ cubic centimeter
• Young's modulus -200Gpa
• Compressive strength 250 Mpa
• Tensile strength -370Mpa
Structural steel differs from concrete in its attributed compressive strength as
well as tensile strength.
• Strength - Having high strength, stiffness, toughness, and ductile
properties, structural steel is one of the most commonly used materials in
commercial and industrial building construction.
• Constructability - Structural steel can be developed into nearly any shape,
which are either bolted or welded together in construction. Structural
steel can be erected as soon as the materials are delivered on site,
whereas concrete must be cured at least 1–2 weeks after pouring before
construction can continue, making steel a schedule-friendly construction
• Fire resistance - Steel is inherently a noncombustible material.
However,when heated to temperatures seen in a fire scenario, the
strength and stiffness of the material is significantly reduced. The
International Building Code requires steel be enveloped in sufficient
fire-resistant materials, increasing overall cost of steel structure
• Corrosion - Steel, when in contact with water, can corrode, creating
a potentially dangerous structure. Measures must be taken in
structural steel construction to prevent any lifetime corrosion. The
steel can be painted, providing water resistance. Also, the fire
resistance material used to envelope steel is commonly water
• Mold - Steel provides a less suitable surface environment for mold
to grow than wood.
Advantages of mild steel
• Continuous weld can be produced
• High level of operation are not required
• Less distortion and hardning
• Less grain growth
• High elastic ratio and endurance stress
• Better machine ability at high hardness
• Greater ductibility at high stength
• Ease of fabrication and speed of construction
• Lower in cost
• High strength to weight ratio.
Disadvantages of mild steel
• Heavy material , installing may not be easy
• Weld may contain slag
• It rust easily
• Cannot made better by heat treatment
• Due to its weight difficult to transport
• Has a high expansion rate in changing temperatures, can suufer fatigue
and cracks and more corrosion
• high density
• Poor electric and thermal conductivity
Uses of mild steel
•Steel frame buildings
•Visually Aesthetic Metal Gate, Fencing etc. Design
• Sections are the most common building materials we used in
• There are many types of sections but it can be classified into two parts-
• Load bearing sections
I sections (parallel flanged column)
c section (channel section)
L section (equal leg angles)
I sections c section L section
• Framed sections
framing sections are those mild steel sections used for framing doors ,
windows , glass panels .
Types of framing sections-
• T section -1 –sash bar
2- glazing bar
• Mullion –at window frames
• Z section- for window shutters
Steel plate is a material often used to make products. This steel can be welded,
formed, machined, sheared, drilled, sawed, punched bolted and riveted. Mainly
used for building ships, bridges, structure for buildings, pressure vessels, industrial
machinery and military equipments, nuclear reactors, penstock, etc.
SOME MANUFACTURING STEPS:
• Minimize internal flaw of the plate.
• Automatic dimension control.
• Reduces thickness deviation.
• Process of rolling and accelerated cooling.
• To produce high tensile steel without any heat treatment.
• Residual stress is removed.
• to provide better flatness of plates.
• Check for flaws, such as blow holes, cracks, etc.
• done to ensure quality.
Consists of welded frames of two verticals & two horizontals of 48.3 mm OD verticals,
braced together with scissor type cross braces secured by spring clips. Bracing is
provided in alternate bays for scaffold heights upto 20m and in all bays for greater
heights. 'H' frame with 60.3 mm OD. verticals are also available for staging of heavier
structures. Available sizes are 2000 x 1250, 1500 x 1250, 1000 x 1250. All other sizes &
finishes are also available.
Manufactured out of 20mm NB pipe.
Suitable for Frame spacing 2.5, 2.0, 1.5 ,1.0 Meters.
Pins are manufactured from mild steel bars with diameters ranging from 9 to 330 mm.
Pin connections are provided when hinged joints are required, i.e., for the connection
where zero moment or free rotation is desired.
Pins are provided in the following cases:
• Tie rod connections in water tanks and elevated bins
• As diagonal bracing connections in beams and columns.
• Truss bridge girders
• Hinged arches
• Chain link cables suspension bridges
Variouus types of pins used for making the connections are forged steel pin, undrilled
pin and drilled pin. To make a pin connection, one end of the bar is forged like a fork
and a hole is drilled in this portion. The end of the other bar to be connected is also
forged and an eye is made. A hole is drilled in such a way that it matches with the hole
on the fork end bar. The eye bar is inserted in the jaws of the fork end and a pin is
placed. Both the forged ends are made octagonal for a good grip. The pin in the joint is
secured by means of a cotter pin or screw.
• mild steel (steel containing a
small percentage of carbon,
strong and tough but not readily
tempered), also known as plain-
carbon steel and low-carbon
steel, is now the most common
form of steel because its price is
relatively low while it provides
material properties that are
acceptable for many applications.
FABRICATION & ASSEMBLY
• Mild steel is hard in nature ,
fabrication is difficult ,only
possible in large factories
• Mild steel could be easily
assembled using welding.
• Mild steel can also attached by
heating and melting method.
HANDLING AND TRANSPORTION
• Comes in large sizes upto 12 m
,handling is tougher then
aluminium or other material
• Mild steel can be sawed , drilled ,
welded on the site.
• Requires heavy machinery for
installing load bearing structures
• Casting Based
• Extrusion Based
• Foil and Powdered Based
• Sheet Based
Forms of Aluminium
• Mild steel sheets
• Doors and Window frames
• Space divider and partition
• Recycled steel can be used for the same applications as
steel produced from virgin material. Products that are
made of recycled steel include:
• Electrical appliances
• Automobiles and other vehicles
• Office supplies
• Hardware such as bolts, nuts, screws etc.
• Construction materials
• Cans and containers
FLAT FALSE CEILING:
The use of such ceiling is done in
mild steel frames are made to carry
Mild steel fascia
External non-load bearing wall
designed to carry its own weight
Sufficient strong to carry wind
Larger sizes can be produced by
using interlocking sections.
Mild steel trusses
• A truss is essentially a triangulated
system of straight interconnected
structural elements. The most
common use of trusses is in
buildings, where support to roofs, the
floors and internal loading such as
services and suspended ceilings, are
readily provided. The main reasons
for using trusses are:
• Long span
• Reduced deflection
• Opportunity to support considerable
•Collapsible Steel Doors
It is use in godowns, workshop, public windows
•Rolling Steel Shutter Door
The door is raised to open it and lowered to close
it. On large doors, the action may be motorized. It
provides protection against wind and rain and it is
use in mainly in shops.
•Mild Steel Sheet Door
It is use in godowns, workshop, public windows
and etc. It is quite strong
Types of mild steel doors
•Corrugated Steel Doors
It is same as above doors except it is mady by
corrugated steel sheets are welded to shutter
frame instead of MI sheets.
• Hollow Metal Doors
This types of doors look like a wooden door but
have more strength and strong compare to wood.
It is made by using strong metal sheets.
Types of aluminiumwindows
A window that cannot be opened, whose
function is limited to allowing light to enter.
A sash window or hung sash window is
made of one or more movable panels or
"sashes" that form a frame to hold panes of
glass, which are often separated from other
panes (or "lights") by narrow muntins
• Metal Windows
Metal windows, made up of mild steel
having lesser cost and more strength