The hot rolled and cold rolled processes of steel are both available for basic carbon steels as well as alloy steels.
Hot rolling is a process in which the steel is heated at a high temperature and then passed over rollers in order to reduce its thickness. This process produces a smooth, highly ductile surface on the steel.
Cold rolling is a process in which the steel is passed over rollers at room temperature. This reduces its thickness by stretching it out and creating alternating layers of hard and soft steel. The resulting product has a rough surface.
This also makes it more flexible and easier to bend into different types of cold-rolled Carbon Steel Round Bars. Different kinds of steel suit specific purposes, despite what may seem obvious. Understanding the method to use for steel might allow you to save money on raw materials. You can also avoid extra processing costs if you understand the method to use. In order to choose which steel to use, it is essential to know the differences between hot and cold steel.
Benefits of Hot Rolling
When it comes to manufacturing steel products, there are two primary methods: hot rolling and cold rolling. Both processes involve the use of enormous rollers that compress the metal into thin sheets. The difference is in the temperature at which the metal is rolled. In hot rolling, temperatures can range from 700 to 1,000 degrees Fahrenheit (about 370 – 537 degrees Celsius), while in cold rolling they’re typically closer to room temperature (65 – 70 degrees F).
Due to its less complex manufacturing process, hot-rolled steel is less expensive than cold-rolled steel. Because hot rolled steel is allowed to cool at room temperature, it is basically normalized, which means that it is free of internal tensions caused by quenching or work-hardening operations. This also makes it more flexible and easier to bend into different shapes than cold-rolled steel.
Whenever dimensional tolerance is less important than material strength, hot-rolled steel is an appropriate choice. Its surface quality is also not a concern. Grinding, sandblasting, or acid-bath pickling are methods that can be used to remove scale from surfaces. Then you can brush or apply a mirror finish after the scaling has been removed. It is also easier to paint and treat descaled steel than untreated steel.
Benefits of Cold Rolling
Cold rolled steel has superior surface properties than hot rolled steel, which means it’s frequently employed for more technically accurate applications or where aesthetics are vital. However, due to the additional processing required for cold finished items, they are more expensive.
The most notable benefit of cold rolling is its ability to provide a much smoother surface finish. The cold rolling process involves passing a sheet of metal through rollers under high pressure and speed while at a temperature below the recrystallization range. This allows the material to be compressed into thinner sheets than hot rolling can achieve, but also leads to a finer grain structure that results in a smoother finish on both sides of the sheet.
The result is higher strength, hardness, ductility, and toughness than hot rolled products—as well as lower wear resistance and increased corrosion resistance compared with both hot rolled and wrought materials (which are generally softer).