Post on 08-Jul-2015
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T H E A L L O Y I N G E L E M E N T S A N D T H E I R E F F E C T O N T H E P R O P E R T I E S
O F S T E E L
• BSME01133079 FAIZ JAWAID
• BSME01133069 BILAL ASHAR
• BSME01133042 ASAD BAJWA
WHAT IS ALLOY?
Alloy is the metal made by the combination of two or more metals
or elements combined to attain certain chemical or mechanical
properties
DIFFERENCE BETWEEN
ALLOY AND COMPOSITE
A Brief Description
Alloy is a mixture of two or more elements where at least one of them
is metal.
Steel is an example for alloy. It is made up of iron and carbon.
Composite is a material made out of two or more constituent materials
which are chemically or physically different.
Concrete is the composite material typically consists of gravels held
with a matrix of cement
A BRIEF HISTORY OF
ALLOYS
Historically, the earliest alloys created by man was brass, a simple
alloy of copper and zinc known to be in use from as early as 3000 BC
King Croesus of Lydia during the years 560-546 BC desired and
developed the first official government coinage system using a
naturally occurring alloy of gold and silver, known as Electrum
ALLOY STEEL
Alloy steel is basically mixture of Iron and Carbon and other trace
elements (Silicon Manganese Sulfur etc)
Carbon %age in steel is about 0.12 - 2%
Carbon
Chromium
Silicon
Manganese
Nickel
Vanadium
ALLOYING ELEMENTS IN
STEEL
Molybdenum
Tungsten
Aluminum
Titanium
Boron
CARBON
Percentage range 0.12 - 2%
Increases hardness
Increases Strength
The basic metal, iron, is alloyed
with carbon to make steel and
has the effect of increasing the
hardness and strength by heat
treatment but the addition of
carbon enables a wide range of
hardness and strength.
CHROMIUM
Percentage range 0.5 - 18%
Increases hardenability of steel (0.5-2%)
Provides Corrosion Resistance (4-18%)
Chromium is added to the
steel to increase resistance
to oxidation. This
resistance increases as more
chromium is added.
'Stainless Steel' has
approximately 18%
chromium and a very
marked degree of general
corrosion resistance when
compared with steels with a
lower percentage of
chromium. When added to
low alloy steels, chromium
can increase the response
to heat treatment, thus
improving harden ability
and strength.
CHROMIUM PROTECTION
Percentage Range 0.2 – 2%
Increases Strength (0.2 – 0.7%)
Spring Steels (0.7 – 2% )
Improve Magnetic Properties (Higher Percentages)
SILICON
This metalloid improves
strength, elasticity, acid
resistance and results in
larger grain sizes, thereby,
leading to greater
magnetic permeability.
Because silicon is used in
a deoxidizing agent in
the production of steel, it
is almost always found in
some percentage in all
grades of steel.
The addition of 2% silicon changes the behavior of the steel drastically for
use in a katana. This spring steel is most commonly seen in application on
fencing foils where it needs to withstand a high degree of bend and still be
able to return to center.
SILICON USE
Percentage Range 0.25 – 1%
When combined with Sulfur Improves Brittleness (0.25-0.40%)
Increases Hardenability (>1%)
MANGANESE
Increases strength at high
temperatures by eliminating
the formation of iron sulfides.
Manganese also improves
hardenability, ductility and
wear resistance. Like nickel,
manganese is an austenite
forming element and can be
used in the AISI 200 Series of
Austenitic stainless steels as
a substitute for nickel.
Percentage Range 2 - 20%
Provide Toughness (2-5%)
Provides Corrosion Resistance (12-20%)
NICKEL
Nickel is added in large
amounts, over about 8%, to
high chromium stainless steel
to form the most important
class of corrosion and heat
resistant steels. These are
the austenitic stainless steels,
typified by 18-8, where the
tendency of nickel to form
austenite is responsible for a
great toughness and high
strength at both high and low
temperatures. Nickel also
improves resistance to
oxidation and corrosion
NICKEL APPLICATIONS
Nickel stainless steel alloy Environmental Protection Agency (EPA)
eliminates a stronger and thicker corrosion-
resistant.
Percentage Range 0 - 0.15%
Stable Carbides-Increase Strength While Retaining Ductility
Promotes fine grain structure (FGS)
VANADIUM
vanadium can produce
stable carbides that
increase strength at
high temperatures. By
promoting a fine grain
structure, ductility can
be retained.
high carbon high chromium die steel with added
carbon and vanadium for abrasion resisting
qualities.
VANADIUM USE
The first large-scale industrial use of vanadium
in steels was found in the chassis of the Ford Model
T, inspired by French race cars.(1927)
Percentage Range 0.2-5%
Stable Carbides
Inhibits Grain Growth
MOLYBDENUM
Found in small
quantities in
stainless steels,
molybdenum
increases
hardenability and
strength, particular at
high temperatures.
Often used in
chromium-nickel
austenitic steels,
molybdenum
protects against
pitting corrosion
caused by chlorides
and sulfur chemicals.
Percentage Range
Hardness at high temperatures
TUNGSTEN
Produces stable carbides and
refines grain size so as to
increase hardness, particularly
at high temperatures
Many high speed steels - those used in cutting and machining tools like saw blades - contain around 18
percent tungsten
Tungsten-steel alloys are also used in the production of rocket engine nozzles, which must have high heat
resistant properties.
TUNGSTEN USES
Percentage Range 0.95 – 1.30%
Increase ductility in steel alloys
commonly used in draw quality steels.
Helps in removing the dissolved oxygen from the
liquid steel. This process is known as killing.
ALUMINUM
ALUMINUM USE
Aluminized steel in different parts of
a car
Percentage Range
Improves Strength
Reduces martensitic hardness in chromium
steels
TITANIUM
Improves both
strength and
corrosion resistance
while limiting
austenite grain size.
At 0.25-0.60
percent titanium
content, carbon
combines with the
titanium, allowing
chromium to
remain at grain
boundaries and
resist oxidization.
TITANIUM USE
EOS has expanded its metal materials portfolio with EOS titanium Ti64ELI and EOS stainless
steel 316L.
EOS titanium Ti64ELI is a light metal alloy that is corrosion resistant and bio-compatible
Percentage range 0.001-0.003%
Powerful hardenability agent
BORON
A hardenability agent that improves
deformability and machinability. Boron is
added to fully killed steel and only needs
to be added in very small quantities to
have a hardening affect. Additions of
boron are most effective in low carbon
steels.
Hot-stamping boron-alloyed steels for
automotive parts
BORON USE
Thank You