Hot rolled steel plate is a steel plate made by rolling steel ingots or continuous casting billets through multiple passes in a rolling mill at high temperatures. Its properties mainly include the following aspects:

1、 Mechanical performance

Strength: Hot rolled steel plates have high strength, especially when processed at high temperatures, which can increase the grain size and direction, improve the traction ability of crystals, and thus enhance strength. However, its strength may be slightly lower compared to cold-rolled steel plates, but it can still meet most application needs.

Hardness: The hardness of hot-rolled steel plates is moderate, generally below 70HB. Although slightly higher in hardness than cold-rolled steel plates (60-65HB), hardness is not the main advantage of hot-rolled steel plates.

Plasticity: Hot rolled steel plates have good plasticity, which makes them suitable for various forming processes such as bending, stretching, compression, stamping, etc. This good plasticity helps to maintain the stability and integrity of the shape of hot-rolled steel plates during processing.

Weldability: Hot rolled steel plates have excellent weldability, which makes them widely used in fields such as construction, bridges, and mechanical manufacturing. The quality of welding performance directly affects the connection quality and overall performance of the component.

2、 Chemical properties

The chemical properties of hot-rolled steel plates mainly include the chemical elements and their contents contained in the steel, as well as the corrosion resistance of the steel. Common chemical elements include carbon (C), silicon (Si), manganese (Mn), phosphorus (P), sulfur (S), and possible alloying elements such as niobium (Nb), vanadium (V), titanium (Ti), etc. These elements have a significant impact on the performance of hot-rolled steel plates:

Carbon (C): It is one of the main elements in steel and has a significant impact on its strength and hardness. The higher the carbon content, the higher the strength and hardness of the steel, but the plasticity and toughness will decrease.

Silicon (Si): It mainly acts as a deoxidizer and can improve the strength and hardness of steel, but excessive silicon can reduce the plasticity and toughness of steel.

Manganese (Mn): can enhance the strength and toughness of steel, while also helping to improve its corrosion resistance.

Phosphorus (P): It is often considered a harmful element in steel because it reduces the plasticity and toughness of the steel. However, in certain specific situations, such as the production of high-strength steel, phosphorus may be added in moderation.

Sulfur (S): It is also considered a harmful element because it reduces the plasticity and toughness of steel and may lead to thermal brittleness.

The addition of alloying elements can further improve the performance of hot-rolled steel plates, such as refining grain size, enhancing strength and toughness, etc.

3、 Other performance

Dimensional accuracy: The dimensional accuracy of hot-rolled steel plates is generally high, and the thickness, length, and width can be controlled within a certain tolerance range to meet the needs of different applications.

Surface quality: Although the surface quality of hot-rolled steel plates may be slightly inferior to cold-rolled steel plates (such as lower smoothness, possible oxide scale, etc.), after appropriate treatment (such as acid washing, sandblasting, etc.), their surface quality can also be significantly improved.

Processing performance: Hot rolled steel plates have good processing performance and can be easily cut, bent, stamped, and welded, making them suitable for manufacturing components of various shapes and structures.

In summary, hot-rolled steel plates have the advantages of high strength, good plasticity, weldability, and certain corrosion resistance, and are widely used in fields such as construction, bridges, machinery manufacturing, and automobile manufacturing. Meanwhile, by adjusting the chemical composition and heat treatment process, the performance of hot-rolled steel plates can be further improved and enhanced to meet different application requirements.