What is Stainless Steel?
Stainless steel is a generic term for a family of corrosion resistant alloy steels containing 10.5% or more chromium.
All
stainless steels have a high resistance to corrosion. This resistance
to attack is due to the naturally occurring chromium-rich oxide film
formed on the surface of the steel. Although extremely thin, this
invisible, inert film is tightly adherent to the metal and extremely
protective in a wide range of corrosive media. The film is rapidly self
repairing in the presence of oxygen, and damage by abrasion, cutting or
machining is quickly repaired.
Benefits of Stainless Steel
Corrosion resistance
All
stainless steels have a high resistance to corrosion. Low alloyed
grades resist corrosion in atmospheric conditions; highly alloyed grades
can resist corrosion in most acids, alkaline solutions, and chloride
bearing environments, even at elevated temperatures and pressures.
High and low temperature resistance
Some
grades will resist scaling and maintain high strength at very high
temperatures, while others show exceptional toughness at cryogenic
temperatures.
Ease of fabrication
The majority of stainless steels can be cut, welded, formed, machined and fabricated readily.
Strength
The
cold work hardening properties of many stainless steels can be used in
design to reduce material thicknesses and reduce weight and costs. Other
stainless steels may be heat treated to make very high strength
components.
Aesthetic appeal
Stainless steel
is available in many surface finishes. It is easily and simply
maintained resulting in a high quality, pleasing appearance.
Hygienic properties
The
cleanability of stainless steel makes it the first choice in hospitals,
kitchens, food and pharmaceutical processing facilities.
Life cycle characteristics
Stainless steel is a durable, low maintenance material and is often the least expensive choice in a life cycle cost comparison.
•Types of Stainless Steel
In
addition to chromium, nickel, molybdenum, titanium, niobium and other
elements may also be added to stainless steels in varying quantities to
produce a range of stainless steel grades, each with different
properties.
There are a number of grades to choose from, but all stainless steels can be divided into five basic categories:
- austenitic
- ferritic
- duplex
- martensitic
- precipitation hardening
These
are named according to the microstructure inherent in each steel group
(a function of the primary alloying elements). Austenitic and ferritic
grades account for approximately 95% of stainless steel applications
Austenitic
When
nickel is added to stainless steel in sufficient amounts the crystal
structure changes to \\\"austenite\\\". The basic composition of
austenitic stainless steels is 18% chromium and 8% nickel. Austenitic
grades are the most commonly used stainless steels accounting for more
than 70% of production (type 304 is the most commonly specified grade by
far).
Ferritic
These are plain chromium stainless steels with varying chromium content between 12 and 18%, but with low carbon content.
Duplex
These
are stainless steels containing relatively high chromium (between 18
and 28%) and moderate amounts of nickel (between 4.5 and 8%). The nickel
content is insufficient to generate a fully austenitic structure and
the resulting combination of ferritic and austenitic structures is
called duplex. Most duplex steels contain molybdenum in a range of 2.5 -
4%.
STAINLESS STEEL PIPES
Stainless
steel Pipes, as an alloy is finding its increasing usage in fields
where hitherto materials such as mild steel, ferrous metals, ceramic
& plastics were used. However because of unique metallurgical
properties of stainless steel such as corrosion resistance, strength to
weight ratio and minimum maintenance cost etc, the usage of stainless
steel piping for as a viable alternative is also gaining rapid
acceptance. As a result, stainless steel now a days has come to be used
in umpteen number of sectors as Oil & Refinery, Petro Chemicals,
Pharmaceuticals, Dairy, Desalination & Chemical sectors.
The World’s Most Important Oil and Gas Exhibition and Conference i.e. the Abu Dhabi International Petroleum Exhibition and Conference, ADIPEC 2016 , is from at Abu Dhabi National Exhibition centre (ADNEC).
That is why we would like to invite you to come over to have a look at our great booth at Stand No. 13704, Hall No. 13. You can join us there for a drink and a friendly chat with the Great Steel and Metals team. It is the perfect opportunity to get to know each other better and learn more about what we have to offer you.