What is Cold Rolled Steel?
Cold rolled steel, sometimes abbreviated to CRS, is well-known for being an extremely ductile material, and is ideal for applications where precision is necessary. It is used in many applications, like household appliances, furniture, lockers, and filing cabinets. In construction applications, CRS is commonly used for building garages, steel sheds, and other industrial buildings.
In simple terms, cold rolling is the process of strengthening steel by changing its shape without using heat. Cold rolling, unlike hot rolling such as with hot rolled steel, can only occur when a metal is below its re-crystallization temperature. Where hot rolling is performed using high temperatures, cold rolling is performed at room temperature. Instead of heat, mechanical stress is used to change the structure of metal. Strain hardening can then increase the metal’s strength by up to 20%, and can also improve a metal’s surface finish.
During the cold rolling process, when the metal is put under mechanical stress, it causes a permanent change to the crystalline structure of the metal. This causes an increase in its strength and often improves corrosion resistance. Along with improving its surface finish, another advantage of cold rolling is better dimensional accuracy.
A cold rolled stainless steel coil can be precision manufactured, allowing the metal to be produced to extremely tight tolerances. The act of work hardening the stainless steel material through cold rolling allows us to achieve various levels of temper, such as quarter-, half- and full hard. The hardness level depends on how much cold work has been done on the steel. Quarter-, half-, and full hard stocks have greater amounts of reduction (sometimes up to 50%). This increases the yield point but decreases the ductility of the steel. Quarter-hard steel can be bent back over itself without breaking, while half-hard can be bent at a 90-degree angle, and full hard can be bent at a 45-degree angle without breaking it. Cold rolled metal is often used in applications where the metal needs to be bent without the risk of breaking.
Cold rolled steel can often be identified by the following characteristics:
- Better, more finished surfaces with closer tolerances
- Smooth surfaces that are often oily to the touch
- Bars are true and square, and often have well-defined edges and corners
- Tubes have better concentric uniformity and straightness
CRS for Construction
When it comes to the construction industry, CRS has been increasing in demand, especially for framing applications. Framing made from cold rolled steel is both lighter and stronger than competing materials. In recent years, CRS framing has become the material of choice for multi-housing buildings like dormitories, hotels, and assisted living facilities.
The physical properties of cold rolled steel make it an ideal building material within many different environments, especially those prone to high winds and earthquakes. But cold-formed steel’s benefits to the construction industry don’t stop there. It’s lighter than comparable building materials, making it easier to ship, handle, and assemble. And as we referenced above, cold rolled steel requires less material for equivalent or greater strength. This means less material is required overall.