The document provides a comprehensive overview of steel, detailing its history, composition, and various properties. Key characteristics such as weldability, hardenability, machinability, and wear resistance are discussed, along with the effects of carbon and alloying elements on steel properties. It also covers the applications of different types of steel, including low, medium, and high carbon steels, alloy steels, and stainless steels.

1. -: Steel Introduction :-
Mr.Prashant Kshirsagar
DGM-Quality

2. -: Contents :-
• Background of metals and steel
• Invention of Steel
• Steel Making Process
• Iron Carbon Phase diagram
• Phases in Steel
• Characteristics of Steel
• Effect of Carbon Steel properties
• Effect of Alloying elements in Steel properties
• High Carbon Steel
• Characteristics of High Carbon Steel
• Application of Steels

3. -: Metals and Steel :-
• Metal is an element, compound or alloy that is a good conductor
of both electricity and heat.
• Metal crystal structure and specific metal properties are
determined by holding together the atoms of a metal
• Steel is an alloy of iron and carbon with less than 2% of carbon
& with substantial quantities of Manganese.
• Steel is most widely used in construction/infrastructure (52%)
and in every aspect of our lives e.g. in cars, refrigerators and
washing machines, cargo ships and surgical scalpels because of
it’s hardness and tensile strength.

4. • Steel production can be traced back nearly 4,000
years to the start of the Iron Age.
• Sir “Henry Bessemer” inventor and engineer who
developed the first process for manufacturing
steel inexpensively (1856), leading to the
development of the Bessemer converter.
-: Invention of Steel :-
996.3MillionT
111.2
2019

5. -: Steel Making Process :-

6. -: Iron-Carbon Phase Diagram :-

7. -: Phases in Steel :-

8. -: Phases in Steel :-

9. -: Characteristics of Steel:-
• Weldability:
• A steels weldability determines how easily a material can be
welded with each other. Materials with low weldability are
likely to crack due to the local stresses caused from heating at the
weld joint. We need to relieve the residual stresses after the
welding through heat treatment process.
• Hardenability:
• A materials hardenability determines how easily the material
can be hardened by thermal treatment.
• The hardenability of steel is a function of the carbon content of
the material, other alloying elements, and the grain size of the
austenite.
• High hardenability refers to the ability of the alloy to produce a
high martensite percentage throughout the body of the material
upon quenching.

10. -:Characteristics of Steel:-
• Machineability:
• Machinability is the ease with which a metal can be cut
(machined) permitting the removal of the material with a
satisfactory finish at low cost. Materials with
good machinability (free machining materials) require little
power to cut, can be cut quickly, easily obtain a good finish, and
do not wear the tooling much.
• Low-carbon steels are "gummy" and stick to the cutting tool,
resulting in a built up edge that shortens tool life. Therefore,
0.20% carbon steel has the best machinability than low C steel.
• Workability:
• Workability is defined as the extent to which a material be
deformed in a specific metal working process without the
formation of cracks. If ductility of the material is high the
material can be mechanically worked with ease.
• Higher strength metals such as high carbon steel have lower
ductility making them far less workable compared to low
carbon steel which has high ductility.

11. -:Characteristics of Steel:-
• Wear Resistance:
• Wear resistance is a materials resistance to surface material
loss due to some form of mechanical action such as abrasion,
erosion, adhesion, fatigue, or cavitation.
• Surface hardness greatly affects the wear resistance of a
material. The high surface hardness of a file allows it to
wear down other metals of lower hardness without
experiencing significant wear itself. The harder materials
provide lower wear rate and friction coefficient.
• Corrosion resistance:
• Corrosion is the loss of metal due to a reaction with the
environment, and is measured as the percentage of weight
loss due to oxidation or other chemical reactions.
• Metals that are going to be exposed to rain, water, humidity, or
anything else that can cause a metal’s surface to oxidize are
vulnerable to corrosion damage. To protect against corrosion
you can use stainless or galvanized steel, titanium,
aluminum, or add & maintain a sealant layer such as paint.

12. Types of Steel
• Carbon Steels only contain trace amounts of elements besides
carbon and iron. This group is the most common, accounting for
90% of steel production. Carbon Steel is divided into three
subgroups depending on the amount of carbon in the metal:
• Low Carbon Steels/Mild Steels (up to 0.3% carbon),
• Medium Carbon Steels (0.3–0.6% carbon), and
• High Carbon Steels (more than 0.6% carbon).
• Alloy Steels contain alloying elements like nickel, copper,
chromium, and/or aluminum. These additional elements are used to
influence the metal’s strength, ductility, corrosion resistance, and
machinability.
• Stainless Steels contain 10–20% chromium as their alloying
element and are valued for their high corrosion resistance. These
steels are commonly used in medical equipment, piping, cutting
tools, and food processing equipment.
• Tool Steels make excellent cutting and drilling equipment as
they contain tungsten, molybdenum, cobalt, and vanadium to
increase heat resistance and durability.

13. -:Effect of Carbon on Properties of Steels:-

14. -:Effect of Alloying elements in Steel:-

15. -: High Carbon Steel :-

16. -: Characteristic of High Carbon Steel :-
• Due to the quality of High Carbon Wire, it plays an important
role in numerous industries such as engineering, construction,
automobile, and so on. Especially the wear characteristics
and higher strength, hardness makes the High Carbon Wire
suitable for many industries such as spring industry, farm
implement industry, and high strength wires.
• Characteristic of High carbon steel:
• High Tensile Strength: The large quantity of carbon enhances
the tensile Strength of material hence used in steel strand,
spring steel wire, steel rope, and steel cord.
• Hardness: The high carbon steel is easily flame hardened and
permits it to work in different forms. It has the highest
hardness and toughness which improve performance.
• Resistance to Wear: The wear resistance increases as the
material becomes harder.
• However, some of the effects of elevated carbon levels include
reduced weldability, ductility, and impact toughness.

17. -: Application of Steel:-