But cold rolled steel undergoes additional processing steps resulting in improved properties that can be exploited for different applications.
Cold rolled sheet metal vs hot rolled.
Hot rolled steel involves rolling the steel at high temperatures where cold rolled steel is processed further in cold reduction mills where the material is cooled followed by annealing and or tempers rolling.
The differences between hot rolled steel and cold rolled steel relates to the way these metals are processed at the mill and not the product specification or grade.
Thus the yield strength of cold rolled steel is higher than that of hot rolled steel.
Cold rolling is done when the metal is able to form new grains as the old ones are deformed by rolling and bending the metal.
In this article we will compare hot rolled vs cold rolled steel sheets.
Cold rolled steel has an oily or greasy finish very smooth surface and very sharp edges.
Typically mills take hot rolled steel after it s mostly or completely cooled and work it to its final dimension by either rolling it extruding it or drawing the metal over a mandrel.
Hot rolled steel comes with a scaly surface slightly rounded edges and corners and the surface is non oily.
Hot rolled steel involves rolling the steel above re crystallization temperatures.
Generally speaking hot roll steel has a rougher surface wider tolerances and lower cost.
The main advantages of cold working are.
Cold rolled has sharper corners and more precise dimensions than hot rolled.
As an example a hot rolled steel product may have a yield strength of 235 mpa.
In short hot rolled steel is processed at the mill at high temperatures and that s it.
Each type of steel has its advantages and disadvantages and costs for the two types of steel are also different.
Whereas cold rolled steel is processed in cold reduction mills followed by annealing and tempering.
In comparison a cold rolled steel product with the same chemical composition has a yield strength of 365 mpa.
On the other hand cold rolled steel is processed as hot roll but once it has cooled to room temperature it received additional processing for different benefits.
Once hot rolled steel has cooled it is then re rolled at room temperature to achieve more exact dimensions and better surface qualities.
Both hot rolled steel and cold rolled steel start out in essentially the same way and both can have the same grades and specifications.
Cold rolled steel is essentially hot rolled steel that has been through further processing.
Hot rolled steel is rolled or shaped at a high temperature while cold rolled steel is rolled at room temperature.
Cold rolled has a smooth and shiny finish while hot rolled has a grey and scaly finish.
Hot rolling and cold rolling are two methods of shaping steel.
There are some fundamental differences between these two types of metal.
Cold worked steels are typically harder and stronger than standard hot rolled steels.
