Processes and characteristics of steel

Stainless steel is an alloy based on iron, whichOver the years, new productive technologies
combines together the mechanical properties ofhave been developed that, using the processes of
steels and some specific features of corrosionstainless steel welding to weld steel pipes, make
resistance. These alloys are also liable to tarnish.possible to market a product of the highest
This means that they have the possibility toquality. It is thanks to the technology of
passivate, that means to get covered with anhigh-frequency welding that in the stainless steel
invisible layer of oxides that protects thepipe, the heat affected zone and known as the
underlying metal from corrosive attacks. Stainlessmost sensitive to corrosion, has been reduced by
steel is the name given to a type of steel withsection and then, for the same alloy, it provides a
high chromium contents that thanks to thislower propensity to oxidation on the surface.
feature does not rust when exposed to waterStainless steel is still refined and adapted to the
and air. They are a very important class of steels,demands of various industries like petroleum,
used in countless applications. In fact, nowadayspetrochemical, mining, energy, nuclear, food and
both stainless steel furniture and constructionobviously building. A lot of machines are built with
machinery are very popular.parts made of steel, from pipes to sheet to steel
The discovery of this type of steel is due totrolleys.
Harry Brearly, who while was experimenting withFor over 70 years stainless steel is used for
various types of alloys for the reeds of guns,external cladding of buildings.
noticed that a type of steel with a certainThanks to the advances in processing and finishing
percentage of chromium did not get rusted whentechnologies of stainless steel, the architects now
exposed to the atmosphere. Later this propertyhave a wide range of high quality and high
was explained by the passivation of chromium,resistance stainless steel. This is also thanks to
which forms a very thin oxide film on thethe characteristics of steel, a highly ductile, flexible
surface, continuous and stable. The followingand easily adaptable material. And that can be
progresses in metallurgy between the forty andrecycled and reused an infinite number of times,
the sixty have extended their development andmaking it an important material for the future and
their applications. They are still refined andfor a sustainable economy.
adapted to the demands of various industriesWhile abroad, the use of stainless steel in cladding
such as oil/petrochemical, mining, energy, nuclearfacades of the buildings is quite common, in Italy
and food industries.the use of stainless steel is more limited.