Cold rolled has a smooth and shiny finish while hot rolled has a grey and scaly finish.
Cold rolled sheet metal vs hot rolled.
During cold rolling the steel is annealed or exposed to heat and allowed to cool which improves ductility.
Each type of steel has its advantages and disadvantages and costs for the two types of steel are also different.
There are some fundamental differences between these two types of metal.
Cold rolled steel is essentially hot rolled steel that has been through further processing.
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.
Hot rolled steel involves rolling the steel above re crystallization temperatures.
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.
The main advantages of cold working are.
But cold rolled steel undergoes additional processing steps resulting in improved properties that can be exploited for different applications.
Whereas cold rolled steel is processed in cold reduction mills followed by annealing and tempering.
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.
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.
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.
Hot rolled steel is rolled or shaped at a high temperature while cold rolled steel is rolled at room temperature.
Cold rolled has sharper corners and more precise dimensions than hot rolled.
Hot rolling and cold rolling are two methods of shaping steel.
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.
In this article we will compare hot rolled vs cold rolled steel sheets.
The smaller products are also much more tolerant than the larger hot rolled versions.
Hot rolling is mainly used to produce simple cross sections or sheet metal.
Once hot rolled steel has cooled it is then re rolled at room temperature to achieve more exact dimensions and better surface qualities.
Thus the yield strength of cold rolled steel is higher than that of hot rolled steel.
As an example a hot rolled steel product may have a yield strength of 235 mpa.
Both hot rolled steel and cold rolled steel start out in essentially the same way and both can have the same grades and specifications.
This looser tolerance makes it easier to force the metal into a variety of different shapes.
When the hot rolled metal cools it will reconfigure making the finished product with a looser tolerance when compared to the cold rolled metal.