Stainless steels and their types, structure, properties, different applications as engineering material and advantages and disadvantages of their use..........
2. High Alloy
Steels,
Ferrous
metal.
Category
The corrosion
resistance of iron-
chromium alloys
was first
recognized in 1821
by the French
metallurgist Pierre
Breathier,
. In the years 1904-
1911, several
researchers,
particularly Leon
Gullet of France,
prepared alloys
that would today
be considered
stainless steel
.
History
Stainless Steel is a
type of steel that is
characterized
primarily by their
corrosion
resistance, high
strength and
ductility , and high
chromium content
Introduction
6. Hardness (Brinell
3000kg)
137-595
Specific Heat
(J/kg-K)
420-500
Hardness (Brinell
3000kg)
137-595
Yield Strength (MPa)
207-552
Tensile Strength
(MPa)
515-827
Melting Point (°C)
1371-1454
Tensile Properties
Elastic Modulus
(GPa)190-210
Density (1000
kg/m3)
7.75-8.1
Percent Elongation
(%) 12-40
Electrical Resistivity
(10-9ῼ-m)
75.7-1020
Poisson's Ratio
0.27-0.3
PROPERTIES OF STAINLESS STEEL
In this section, we are going to discuss properties of stainless steel which we consider
before bringing it into work.
Mechanical Properties:
7. Chemical Properties:
• Chromium is added to steel to
make it resistant to rust.
• Stainless steel forms a
passivation layer of
Chromium (III) Oxide.
•The other minor constituents of steel are
nickel, nitrogen, molybdenum and
aluminum. Nickel increase the corrosion
resistance further.
8. PHYSICAL PROPERTIES:
Stainless steel is very
strong. This form of steel
can withstand very high
and very low heats while
still maintaining a solid
but flexible shape.
The steel is also unlikely to
deteriorate or rust as
other metals are known
to do. This lack of
permeability and chemical
reaction helps the
stainless steel maintain its
initial integrity and
strength.
Stainless steel is not
known as a good
conductor of heat or
electricity,
which makes the material
safe in the construction,
manufacturing and
cooking industries.
Strength
Stain
Resistance Conductivity
9. Applications Of stainless Steel
Stainless steel is an attractive material for a variety of applications, usually due to the
corrosion resistance and strength. Amongst the fields which make great use of stainless
steel are the following:
I. Medical and Surgery Equipment:
Medical and
Surgery
Equipment
Automotive
Industry
Chemical and
Petrochemical
Industry
Architecture,
building and
construction
11. Advantages of stainless steel
More Hygienic
Ease of
Fabrication
Easy to Clean
and Maintain
Ease of
Fabrication
Attractive
Appearance
Strength-to-
weight
Advantage
Aesthetically
Pleasing
Won't Discolor
or Stain
High Corrosion
Resistance
12. Disadvantages of stainless steel
Dirt Shows Difficult to Weld
Difficulty in
Fabricating
Difficult to
Machine
High Initial Cost
High Polishing
Cost
Scratches And
Dents
Poor conductor
of heat