Last Updated on October 12, 2023 by assistant
Hot rolled steel and cold rolled steel are two processes commonly used in sheet metal manufacturing. They differ in their manufacturing processes, the properties of the resulting materials, and their respective applications. In this article, we mainly explain the various characteristics and applications of hot-rolled steel plates and cold-rolled steel in sheet metal processing.
Hot rolled steel plate
Hot-rolled plates, that is, hot-rolled steel plates and steel strips, are commonly known as hot plates. Usually, rolling is also written as zhao, such as hot-rolled plate, but they all refer to the same hot-rolled plate. Refers to steel plates with a width greater than or equal to 600mm and a thickness of 0.35-200mm and steel strips with a thickness of 1.2-25mm. Hot rolled steel plate usually refers to the process of rolling steel plates or steel coils at high temperatures.
The process involves heating the steel above its recrystallization temperature, typically about 1,000 to 1,300 degrees Celsius (1,800 to 2,400 degrees Fahrenheit), and then passing it through a series of rollers to achieve the desired thickness.
Characteristics of hot rolled steel
Hot-rolled steel has a characteristic scale or rough surface due to the oxide layer that forms during heating. Scale is usually removed through additional processing steps or by pickling and oiling.
The mechanical properties of hot-rolled steel plates are far inferior to those of cold processing and inferior to forging processing. Hot-rolled steel tends to have lower tensile strength and yield strength than cold-rolled steel. However, it exhibits greater malleability and is easier to shape and style.
Hot-rolled steel is generally cheaper than cold-rolled steel due to a simpler manufacturing process. This product has the tendency to partially replace cold-rolled plates, is moderately priced, and is very popular among users.
Applications of hot rolled steel
Hot rolled steel is often used in applications where strength and durability are primary considerations. Some examples include structural components in buildings, railroad tracks, automobile frames, agricultural equipment, and large pipelines.
Cold rolled steel plate
Cold rolled steel plate refers to the process of rolling steel plates or coils at room temperature or slightly below room temperature. Steel is typically processed through a series of rollers to reduce its thickness and improve its surface finish.
Characteristics of cold rolled steel
Cold rolled steel has a smoother and more refined surface than hot-rolled steel. It has a matte or semi-matte finish without the scaling commonly found in hot-rolled steel.
Cold rolled steel has higher tensile strength and yield strength than hot rolled steel. It has a more uniform grain structure, which helps improve mechanical properties and dimensional accuracy.
Cold rolled steel has better dimensional accuracy and tighter tolerances than hot rolled steel.
Cold rolling increases the hardness of steel, making it suitable for applications requiring greater strength and hardness.
Cold rolled steel applications
Cold-rolled steel is typically used in applications that require a smooth surface finish, precise dimensions, and high mechanical properties. It is commonly used in the manufacture of appliances, automotive parts, metal furniture, electrical enclosures and high-quality steel.
In summary, hot-rolled steel is processed at high temperatures, resulting in a rough surface finish and lower mechanical properties. It is commonly used in applications where strength and cost effectiveness are required. Cold-rolled steel, on the other hand, is processed at room temperature or lower, resulting in a smoother surface finish, improved mechanical properties, and dimensional accuracy. It is typically used in applications that require a higher quality finish and tighter tolerances.
In addition, the production processes of hot-rolled steel plates and cold-rolled steel plates are different. Generally speaking, cold-rolled steel sheets have better strength and hot-rolled steel sheets have better ductility. Cold rolling generally has a smaller thickness, while hot rolling can have a larger thickness. The surface quality, appearance, and dimensional accuracy of cold-rolled steel plates are better than those of hot-rolled plates, and the thickness of its products can be reduced to about 0.18mm, so it is more popular. If you have projects that require sheet metal processing and production of hot-rolled steel plates and cold-rolled steel plates, please contact us and we will provide you with a free quotation service.