As you order a batch of steel from a service company, you may encounter the terms “hot-rolled” and “cold-rolled.” You need to understand the difference between the two as the difference will help you choose the right kind of steel for different applications you may need for your industry.
In layman’s terms, “hot-rolled” and “cold-rolled” refer to two distinct steel processing. Steel manufacturers process steel with heat when “hot-rolling.”
Hascall Steel Company defines hot rolled black “…as the least processed form of carbon steel. It is the base metal for other steel types, produced when the metal is rolled above its re-crystallization temperature…”
On the other hand, “cold-rolling” requires near or at room temperature during processing. Both processing can change the overall performance and the application of steel.
Hot-rolling and cold-rolling exclude formal specifications and grades of steel. Specifications and grades only refer to the metallurgical composition and performance ratings of steel and not the processing. Different grades and specifications of steel can either be hot or cold-rolled. You can keep these in mind to prevent confusion.
How It Works: Hot-Rolling
As for the processing themselves, hot-rolling involves heating steel up to its melting point while shaping the steel at the same time. Hot-rolling process changes the composition of the steel. The steel becomes more malleable in this way, yet once cool, the final shape can be difficult to control. The processing makes hot-rolled steel suitable for imprecise applications such as in construction.
How It Works: Cold-Rolling
Cold-rolling involves heating and allowing the steel to cool, improving ductility. Once cooled, the steel can be shaped at or near room temperature, enhancing the hardness of the steel. Cold-rolled steel can be used for more precise or aesthetic applications such as in cars or bicycles. You will need additional processing for such applications, however, adding to costs.
With your better understanding of hot-rolled and cold-rolled steel, you can better choose which kind of processed steel you need for your applications. A steel services company can help you with your order and even teach you more about steel.