This document discusses steel, including its composition, types based on carbon content, physical properties, and factors affecting properties. It describes mild steel as containing 0.15-0.25% carbon and being very ductile, malleable, and elastic. Medium carbon steel contains 0.25-0.70% carbon and is used for tools and machinery. High carbon steel has 0.70-1.5% carbon and is tougher, stronger, and resists corrosion. The physical properties of steel include high strength-to-weight ratio, dimensional stability, conductivity, durability, and recyclability. Carbon content, impurities, heat treatment processes affect the properties of steel.

1. GOVERNMENT ENGINEERING COLLEGE
GANDHINAGAR
Vyomee Bagiya 220130141052
Heer Gokani 220130141015
Mahetab Ghanchi 220130141013
Nirali Chauhan 220130141009
STEEL

2. TABLE OF CONTENTS
Introduction
Classification of
steel based on
carbon content
Physical
properties
Factors affecting
physical properties
01
02
03
04

3. TABLE OF CONTENTS
Market forms
of steel
Uses
05
06

4. Introduction
Steel is comprised mostly of Iron and has some carbon mixed in
different proportions to create different kinds of steel. While carbon
is the main property changing factor, other alloying metals are also
added such as sulphur, phosphorus, manganese, silicon, etc.

5. TYPES
BASED ON
CARBON
CONTENT
MILD
STEEL
MEDIUM
CARBON
STEEL
HIGH
CARBON
STEEL
0.15-0.25% 0.25-0.70%
0.70-1.5%
OTHERS

6. MILD STEEL
● 0.15-0.25%
Carbon
● 0.05%
Sulphur
● 0.055%
Phosphorus
Composition
● Very ductile,
malleable, elastic.
● Easily forged, welded
or riveted.
● Strong in
compression,
tension and shear.
Properties
● Manufacturing of rolled
structural sections.
● Bars for reinforcements of
concrete and sheets for
roof coverings.
● For making equipments,
tools and machine parts.
Uses

7. MEDIUM CARBON STEEL
● 0.25-0.70%
Carbon
● 0.9%
Manganese
● 0.05%
Sulphur
● 0.04%
Phosphorus
Composition
● Granular structure.
● Easy to harden and
temper, difficult to
forge and weld.
● Stronger in
compression than
tension and shear.
● Absorbs shocks and
vibrations.
Properties
● Making tools like
drills, files, chisels.
● Machines needing
durable and shock
absorbing parts.
● Railway wheels, and
tracks, gears,
crankshafts.
Uses

8. HIGH CARBON STEEL
● 0.70-1.5%
Carbon
● 0.6%
Manganese
● 0.2% Silicon
● 0.05% Sulphur
● 0.05%
Phosphorus
Composition
● Tougher and more
elastic.
● Increased tensile
strength, high
hardness.
● Brittle and less
ductile.
● Resists corrosion.
Properties
● For reinforcing
pre-stressed
concrete
structures.
● In tools and die
steels.
Uses

9. OTHERS
DEAD MILD STEEL
(<0.15% C)
● Most abundant
grade of steel,
least expensive.
● Good weldability.
● Unresponsive to
heat treatment,
need cold working
to improve
strength.
01
02
CAST STEEL/CARBON
TOOL STEEL (>1.5%C)
● Crystalline
structure, brittle.
● Easy to cast into
any shape.
● Does not rust.
● Easy to recycle.

10. PHYSICAL PROPERTIES
Lowest of all
building materials
available.
Strength to
weight ratio
Dimensional
stability
Ductility
Conductance
Recyclable
Remains
unchanged for
many years or after
subjected to
extreme
environmental
conditions.
Can be easily
molded into any
shape.
Good conductor of
electricity and heat.
Efficient to recycle
without losing its
properties.

11. PHYSICAL PROPERTIES
Good durability for
a building material.
Durability
Resistance to
corrosion
Quality
Does not corrode
easily on exposure
to moisture like its
constituents iron
and carbon.
Higher carbon
content gives more
strength and high
quality steel with
less carbon is more
ductile. Now it is
manufactured to
ensure good
strength and
ductility by rapid
cooling.

12. FACTORS
AFFECTING
PHYSICAL
PROPERTIES OF
STEEL

13. Factors affecting physical properties
Tensile strength of steel increases with carbon content up to
0.8% and decreases after that.
Ductility, hardness and strength also increases with carbon
content.
Carbon Content
01
02 Presence of Impurities
If sulphur content in steel is between 0.02-0.10%, it has no
appreciable effect on ductility and strength of steel.
Excess sulphur will decrease ductility and strength.

14. 03
The phosphorus content in steel should be below 0.12%. Excess
phosphorus reduces ductility, strength and shock resistance.
If silicon content is less than 0.20%, it has no effect on physical
properties. If it is increased to 0.30-0.40$, elasticity and strength
increases without reduction in ductility.
Manganese helps to improve strength of mild steel. Desirable
content is 0.30-1.0%. If it exceeds 1.50%, steel becomes very
brittle.
Heat Treatment Processes
Most steel are subjected to 3 basic processes:
annealing, quenching and tempering.

15. Steel is heated beyond its critical temperature for the annealing
process.During this phase, the grain quality of the steel changes.
Heat treated steel must be tempered before it can be used as a
commercial material. Tempering is also heating steel, but this
time below the critical temperature.
Tempering steel is a way to make hardened steel less brittle and
change its durability to suit your needs.
Quenching is the industry term for rapidly cooling hot steel to
make it hard again. Depending on the project, hot and malleable
steel will be dipped in either water or oil to cool. This brings the
steel back to a solid state and often leaves it brittle.

16. Market Forms of Steel

17. Market Forms of Steel