Cold worked steels are typically harder and stronger than standard hot rolled steels.
Cold rolled vs hot rolled sheet steel.
Whereas cold rolled steel is processed in cold reduction mills followed by annealing and tempering.
The steel is processed further in cold reduction mills where the material is cooled at room temperature followed by annealing and or tempers rolling.
Although this combines two processes the method as i will point out later has an advantage of economy and scheduling in the cold formed process.
First hot rolled steel coil is manufactured and later it is run through a mill which forms the coil into the steel sheet pile sections.
In this article we will compare hot rolled vs cold rolled steel sheets.
Basic difference between hot rolled and cold rolled steel is the way they are processed.
Cold rolled has sharper corners and more precise dimensions than hot rolled.
Cold formed is manufactured in two steps.
Hot rolling and cold rolling are two methods of shaping steel.
This process is called hot rolling.
During cold rolling the steel is annealed or exposed to heat and allowed to cool which improves ductility.
Cold rolled has a smooth and shiny finish while hot rolled has a grey and scaly finish.
During the hot rolling process steel is heated to its melting point while being worked changing the composition of the steel to make it more malleable.
Hot rolled steel involves rolling the steel above re crystallization temperatures.
There are three main visual differences between the two processes.
Hot rolled steel is rolled or shaped at a high temperature while cold rolled steel is rolled at room temperature.
Finished products created by the cold rolled steel process include bars strips rods and sheets which are usually smaller than the same products available through hot rolled methods.
When the rolling is done above a certain temperature it prevents the steel from recrystallizing.
When to use hot rolled steel.
Cold rolled steel is essentially hot rolled steel that has had further processing.
Hot rolled steel is used in situations where precise shapes and tolerances are not required.
Alternatively cold rolled steel has sharp edges a very smooth surface texture and an oily or greasy feel to it.
The smaller products are also much more tolerant than the larger hot rolled versions.
Rolling performed below a specific temperature will allow for recrystallizing and is called cold rolling.