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How is stainless steel made

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How is stainless steel made?
Until the 1950s and 1960s, when the development of AOD (argon oxygen decarburization)
and VOD (vacuum oxygen decarburization) was seen, the process of manufacturing stainless
steel was time-consuming and costly. However, these two developments have revolutionized
the production of stainless steel, significantly reducing raw material costs, increasing
productivity and improving quality. This has led to the remarkable growth of steel production
from the 1970s to the present.
How is stainless steel made?
The properties of the final alloy can be refined by varying the number of various elements.
Importance of chromium in the manufacture of stainless steel
There is no viable alternative. Chromium is a tough, corrosion-resistant transition element
that gives stainless steel corrosion resistance. In general, the higher the chromium content, the
more resistant the steel to corrosion.
Removal of carbon content
This is done by processing the molten metal with an AOD (Argon Oxygen Decarburization)
converter. The converter reduces carbon by injecting a mixture of oxygen and argon. At this
stage, alloying elements such as nickel and molly can be added to the AOD
converter.Alternatively, if you need very low carbon content, you can use a VOD (Vacuum
Oxygen Decarburization) converter.
Tuning
Most stainless steels have strict quality requirements. Adjustment is slowly stirring the steel
to remove unwanted elements and improve consistency while keeping the required
composition within the temperature limits. Tube Fittings manufacturers in India gives you
the best type of stainless steel in India.
Forming
Now the molten steel is cast into a shape. Instrumentation Valve manufacturers provide
you the best valve of stainless steel.
Hot rolling
Hot rolling occurs at temperatures above the recrystallization temperature of steel. The exact
temperature depends on the desired grade of stainless steel. The steel foam is heated and
passes through the high rollers. Flowers and billets are formed into sticks and wires. Slabs are
formed on plates, strips, and sheets.
Cold rolling
Cold rolling is used when very accurate dimensions or attractive finishes are required. This
process occurs below the recrystallization temperature of steel. Cold rolling is performed by a
small diameter roller and a series of support rollers. This process allows you to produce wide
sheets with an improved surface finish.
Annealing
Annealing is a process used to soften stainless steel, improve ductility, and refine the particle
structure. It is also used to relieve the internal stress of the metal caused by previous
processes.
Decalcification
The annealing process causes the steel to come off. These scales are usually removed by
pickles, which involves immersing the steel in hydrofluoric acid. Electrical cleaning is an
alternative method of using an electric current to remove scale.
Cut
Now you can cut the stainless steel to the right size. Mechanical cutting is the most common
method. Stainless steel can be cut straight with a guillotine knife, circular with a circular
knife, sawed with a high-speed blade, or cut with a punch and die. Other methods include
flame cutting using a flame torch powered by oxygen, propane, or iron powder, or plasma jet
cutting using a column of ionized gas combined with an electric arc.
Sophistication
For stainless steel products, surface finish is important, especially in applications where
appearance is important.
Grinding wheels or polishing belts are commonly used to grind or polish steel. The smooth
surface provides better corrosion resistance.
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