Wuxi Guoyin Metal Material Co., Ltd.

The difference between cold rolled steel plate and hot rolled steel plate

The difference between cold rolled steel plate and hot rolled steel plate
1. Distinguish by carbon content

The carbon content of hot-rolled steel plates is slightly higher than that of cold-rolled steel plates. The density is the same even if the ingredients are not much different. But if the ingredients are very different, for example, the density of stainless steel, regardless of cold-rolled or hot-rolled steel plates, is around 7.9g/cm3. It depends on the composition. Hot-rolled steel plates are just more ductile, and steel is also subject to pressure.

2. Distinguish by density

Hot-rolled steel plates are divided into structural steel, low carbon steel, and welding cylinder steel. Then search for the steel you need based on various steel materials and check the density and composition of the specific steel.

Hot-rolled steel plates have low hardness, are easy to process, and have good ductility. The surface quality of hot-rolled steel plates is poor (with oxidation and low finish), but it has good plasticity. It is generally a medium-thick plate or a cold-rolled plate with high strength, high hardness and high surface finish. It is generally a thin plate and can be used as a stamping plate.

Cold-rolled plates have high hardness and are relatively difficult to process, but they are not easily deformed and have high strength.

3. Distinguish by production process

The production processes of hot-rolled steel plates and cold-rolled steel plates are different. Hot-rolled steel plates are rolled at high temperatures, while cold-rolled steel plates are rolled at room temperature. Generally speaking, cold-rolled steel plates have better strength and hot-rolled steel plates have better ductility. China Steel Spot Network has detailed quotation differences between hot-rolled steel plates and cold-rolled steel plates. 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 product thickness is reduced to about 0.18mm, so it is more popular. For product acceptance, you can ask professionals to do it.

The mechanical properties of hot-rolled steel plates are far inferior to those of cold processing and inferior to forging processing, but they have better toughness and ductility.

Due to a certain degree of work hardening, cold-rolled steel plates have low toughness, but can achieve a good yield-to-strength ratio and are used to cold-bend spring sheets and other parts. At the same time, because the yield point is closer to the tensile strength, there is no risk during use. Predictability, accidents are likely to occur when the load exceeds the allowable load.

the difference:

1) The cold plate is cold-rolled and has no oxide scale on the surface and is of good quality. Hot-rolled steel plates are hot-rolled and have oxide scale on the surface, and the plate thickness varies.

2) Hot-rolled steel plates have poor toughness and surface smoothness and are relatively low-priced, while cold-rolled steel plates have good stretchability and toughness, but are more expensive.

3) Rolling is divided into cold-rolled and hot-rolled steel plates, with the recrystallization temperature as the distinguishing point.

4) Cold rolling: Cold rolling is generally used to produce strips, and its rolling speed is relatively high.

Hot rolled steel plate: hot rolling temperature and forging temperature

5) The surface of the hot-rolled steel plate without electroplating is dark brown, and the surface of the cold-rolled plate without electroplating is gray. After electroplating, it can be distinguished by the smoothness of the surface. The smoothness of the cold-rolled steel plate is higher than that of the hot-rolled steel plate.