What Is Carbon Steel Profile?
Carbon steel is an iron alloy that includes varying amounts of carbon. This determines its tensile strength, hardness and ductility.
Mild steel has a low carbon content and is easier to shape, form or weld than higher-carbon varieties. You can find mild steel in many everyday items like building frames, car parts and springs.
Hot Rolled
There are a number of different types of steel that work well for many purposes, but one of the most important distinctions to make is between hot and cold rolled. The manufacturing method for a steel type can impact its strengths, durability, and dimensional tolerances. Understanding the differences between these materials can help engineers choose the right option for their projects.
Hot rolled steel is made by heating slabs of metal to temperatures well above their recrystallization point. This allows the steel to be formed and shaped without cracking. It is then cooled gradually, which helps it to essentially normalize and become free of internal stresses. This type of steel tends to be less expensive than cold rolled.
You can find hot rolled carbon steel in railroad equipment, and it’s often used in other structural applications where surface finish and tight dimensional tolerances aren’t a concern. For instance, base plates and brackets for trailer fabrication use this type of steel. You may also find this material in abrasion resistant structures and gas tanks.
Cold Rolled
Essentially, cold rolled carbon Carbon Steel Profile steel is hot rolled metal that has undergone additional processing. This process allows for a more precise dimensional tolerance range and a smoother surface finish, and is the preferred method for projects where aesthetics are a key concern.
Additionally, because it is shaped at lower temperatures, cold worked steels are harder and stronger than standard hot rolled metals. However, these additional treatments can also create internal stress in the material, which can lead to unpredictable warping if the steel is not properly stressed relieved before cutting, grinding, or welding.
Another key benefit of cold rolled carbon steel is its ability to be coated in a variety of protective materials, such as paint. This can help protect the metal from rust and weathering over time, making it a great choice for projects that will be spending some time outdoors or in highly corrosive environments. This can include things like guardrails and various outdoor machinery framing.
Hot Formed
The process of rolling plays a significant role in the final performance of carbon steel. Hot rolled and cold rolled carbon steel go through similar initial processes but the difference in how the metal is finished impacts its overall quality.
Cold rolled steel requires less processing than its hot counterpart, and has the benefit of having fewer inconsistencies that can impact accuracy. However, the extra steps required to achieve these tighter tolerances can make it more expensive than hot rolled carbon steel.
When considering a new project, it is important to balance the desired outcome with the available timeline and budget constraints. Understanding the differences between these different types of carbon steel can help you select the right material for your needs.
At FastMetals, we offer hot rolled pickled and oiled (HRP&O) carbon steel in various sizes and shapes, such as round bar, flat bar, square bar, tube, angle, and channel. This mild steel option has been washed in acid to Q195 steel pipe remove mill scaling and is more corrosion resistant than unwashed hot rolled carbon steel. This makes it a good choice for projects that require weather resistance, such as guardrails.
Cold Formed
For many projects, structural engineers may choose to use cold formed steel in place of other materials. It is an affordable and durable material that offers the load-carrying capabilities needed in building frames. It can also help to meet environmental considerations. For example, it can be used in construction projects in rural and remote areas where timber framing is impractical due to the need for specialized transportation and storage.
Compared to hot rolled carbon steel, cold forming produces a product with a higher hardness level and a more precise tolerance. This means less waste and splice welding, as well as a lower risk of warping due to excessive working of the steel. In addition, it retains little to no mill scaling, and is non-shrinking and non-creeping at ambient temperatures.
It is also an ideal material for welded applications. It can be cut to a specific length, possibly perforated and then welded without the need for further processing. This reduces costs and speeds up the construction process. This is particularly true for projects that require complex shapes that would be difficult or costly to fabricate using other methods.
Heat Treated
Carbon Steels can be made harder, softer, or tougher by exposing them to specific temperatures for a period of time. These temperature exposures, known as Heat Treatment, alter the shape of their crystalline structure and change their properties. There are several types of heat treatments that can be used on Carbon Steels. These include Hardening, Annealing, Normalizing, Case Hardening, Nitriding, and Tempering.
The annealing process is done by heating the steel to a certain temperature and then allowing it to cool slowly. This allows the steel to become softer and more flexible without losing its strength. It also helps to prevent internal stresses and distortions from occurring during hot working.
The normalizing process involves heating the steel to a temperature higher than the annealing temperature and then lowering it to room temperature. This allows the steel to become softer, more flexible, and more resistant to stresses and distortions. It is usually performed for parts that will be exposed to high levels of stress. This process also makes the metal easier to machinable and increases its wear resistance.
