Essentially, cold rolled steel refers to hot rolled steel that has undergone further processing. As mentioned earlier, rolling involves the range of processes involved in forming the steel, including turning, grinding, and polishing. The other operations modify an existing hot rolled steel into a more refined product. The term "cold rolled" essentially applies to steels that have undergone compression.
While making hot rolled steel only involves heating at high temperatures and cooling, cold rolled steel involves an additional process. At the cold reduction mills, the manufacturer cools the steel and re-rolls it at room temperature either by cold roll forming or press-braking. This process helps to achieve desired shape and dimensions.
Properties of Cold Rolled Steel
The following features will help you identify cold rolled steel:
Smooth surfaces usually have an oily-like touch
The surface has better finish qualities and tighter tolerances
Square bars come with well-defined edges
Tubes often possess better straightness and concentric uniformity
Benefits of Cold Rolled Steel
Here are some of the benefits you can get from using cold rolled steel:
Better Surface Properties: Parts made with cold rolled steel often have smooth and shiny surfaces void of scale or rust. Thus, making them useful when aesthetics is essential.
Greater Strength: They are typically stronger and harder (up to 20% greater strength) than hot rolled steel. This makes them useful for high-stress applications.
Higher Precision: Since cold rolled steel does not shrink while forming, it allows for the fabrication of more precise parts with consistent and accurate shapes.
Various Surface Finish: It supports an extensive range of surface finishes.
Drawbacks of Cold Rolled Steel
More expensive due to the additional processing involved.
Internal stresses occur in the material due to additional treatments leading to unpredictable warping in some cases.
Fewer shapes are available, e.g., sheets and box section shapes.
Common Uses of Cold Rolled Steel
The ideal applications for cold rolled steel are those requiring better metal surface finishing and tighter tolerances. Examples of such components include the following:
- Aerospace parts
- Mechanical components
- Home appliances
- Rods, bars, strips, and sheets
- Metal furniture structures
CR Coil
