CR500/780DP dual-phase steel is a high-strength, high-plastic dual-phase steel with high strength and ductility, and is an advanced automotive steel. Among them, 500 and 780 in CR500/780DP represent their yield strength respectively, and the unit is MPa. Duplex steels are composed of iron, carbon and alloying elements, and their microstructure consists of two different grain phases, soft ferrite and hard martensite. This structure makes dual-phase steel not only have high strength and hardness, but also good plasticity and ductility, which is suitable for key parts such as automobile body structure, chassis and safety components. The production process of dual-phase steel is relatively complex, requiring precise chemical composition and heat treatment process to obtain the desired microstructure and properties.

What is the chemical composition of CR500/780DP dual phase steel?

Carbon content: 0.12%-0.18%

Silicon content: ≤0.50%

Manganese content: 1.20%-2.00%

Phosphorus content: ≤0.030%

Sulfur content: ≤0.025%

Chromium content: ≤0.50%

Molybdenum content: ≤0.10%

Vanadium content: ≤0.10%

What is the performance of CR500/780DP dual phase steel?

High strength: The yield strength of CR500/780DP dual-phase steel is usually between 500-780 MPa, which is much higher than ordinary low-alloy steel and hot-rolled ordinary carbon steel, and can provide better rigidity and bending resistance.

High plasticity: Another distinguishing feature of dual-phase steel is its high plasticity, that is, its ability to deform better under stress. This high plasticity enables CR500/780DP dual-phase steel to absorb greater impact energy and improve the safety performance of automotive structures.

Good welding performance: CR500/780DP dual-phase steel has good welding performance and can be connected by various welding methods, such as spot welding, lap welding, laser welding, etc., to realize the assembly of automobile body structures.

Good formability: CR500/780DP dual-phase steel has excellent formability, can adapt to complex car body designs, and has good surface quality and dimensional stability.

Good corrosion resistance: Duplex steel has good corrosion resistance and can resist the erosion of some external corrosion factors, such as water, salt, acid, etc., thereby prolonging the service life of the car.

What is the production process of CR500/780DP dual-phase steel?

Steelmaking: First of all, high-quality molten steel needs to be refined. Usually, high-temperature furnaces such as electric arc furnaces and converters are used for steelmaking. During the steelmaking process, appropriate amount of alloying elements are added and the chemical composition is finely adjusted to control the composition and temperature of molten steel, as well as to obtain the desired quality of molten steel.

Continuous casting: casting the refined molten steel through a continuous casting machine, usually using the “thin-slab-thin-slab” continuous casting technology. In this process, by adjusting the crystallizer structure and process parameters of the casting machine, parameters such as the width, thickness, and shape of the steel plate can be controlled to obtain the required steel plate size and quality.

Hot rolling: After continuous casting, the billet needs to be processed by a hot rolling mill to form the final CR500/780DP dual-phase steel plate. During the hot rolling process, by adjusting parameters such as rolling temperature, rolling process, and subsequent cooling methods, parameters such as the structure, mechanical properties, and shape of the steel plate can be adjusted to meet different application requirements.

Annealing treatment: In order to further adjust the structure and properties of the steel plate, it is usually necessary to anneal the hot-rolled steel plate. This annealing treatment is to adjust the microstructure and mechanical properties of the steel plate by heating the steel plate to a certain temperature, and after holding it for a certain period of time, and then through different cooling methods.

Surface treatment: In the process of steel plate processing, in order to improve its surface quality and corrosion resistance, it is usually necessary to carry out surface treatment on the steel plate. This surface treatment usually includes galvanizing, coating, polishing and other processes to meet different application requirements.

What is the heat treatment process of CR500/780DP dual-phase steel?

The heat treatment process of CR500/780DP dual-phase steel usually includes the following steps:

Hot rolling: After continuous casting, the billet needs to be processed by a hot rolling mill to form the final CR500/780DP dual-phase steel plate. During the hot rolling process, by adjusting parameters such as rolling temperature, rolling process, and subsequent cooling methods, parameters such as the structure, mechanical properties, and shape of the steel plate can be adjusted to meet different application requirements.

Continuous heat treatment: After hot rolling, CR500/780DP dual-phase steel usually requires continuous heat treatment to further optimize the structure and mechanical properties of the steel plate. The continuous heat treatment process usually adopts continuous annealing and continuous cooling process, and the continuous annealing process usually adopts a two-stage temperature control process to control the structure and mechanical properties of the steel plate.

Batch heat treatment: After continuous heat treatment, batch heat treatment is usually required to further improve the performance of the steel plate. This heat treatment usually adopts a furnace quenching process, in which the steel plate is first heated in a high-temperature furnace, and then the structure and mechanical properties of the steel plate are adjusted through the quenching process.

Passivation treatment: In order to improve the corrosion resistance of CR500/780DP dual-phase steel plate, it is usually necessary to passivate the steel plate. This treatment usually uses electrophoretic coating, spraying and other processes to form a uniform oxide layer, thereby improving the corrosion resistance of the steel plate.

What precautions should be taken during the use of CR500/780DP dual-phase steel?

Avoid excessive bending and cutting of the dual-phase steel plate, so as not to damage the surface and internal structure of the steel plate, thereby affecting the mechanical properties and service life of the steel plate.

Pay attention to avoid excessive shock and vibration of the dual-phase steel plate, so as not to cause fatigue fracture and cracks of the steel plate, thereby affecting the service life and safety performance of the steel plate.

While using dual-phase steel plates, it is necessary to pay attention to environmental climate and temperature factors, especially in high temperature, humid or highly corrosive environments, it is necessary to take corresponding protective measures to avoid rust and corrosion on the surface of the steel plate. question.

When processing dual-phase steel plates, it is necessary to adopt appropriate processing methods and process parameters according to the hardness, plasticity and other parameters of the steel plate to avoid excessive damage to the surface and internal structure of the steel plate, thereby affecting the mechanical properties and service life of the steel plate.

When transporting and storing duplex steel plates, care should be taken to avoid excessive friction, extrusion, and scratches on the steel plates, especially during handling and storage, and corresponding protective measures should be taken to avoid damage to the steel plates.

What are the applications of CR500/780DP dual phase steel?

CR500/780DP dual-phase steel is a high-strength, high-plasticity automotive sheet, which is widely used, mainly including the following aspects:

Automotive structural parts: The high strength and high plasticity of dual-phase steel make it the preferred material for automotive structural parts, such as doors, roofs, bottoms, front and rear bumpers, etc.

Airbag container: Duplex steel plate has high strength and good formability, and can be made into an airbag container to ensure the effectiveness and stability of the airbag.

Motorcycle frame: Dual-phase steel plate has high strength, high stiffness and excellent formability, and is suitable for manufacturing motorcycle frames and other components.

Construction machinery: The high strength and wear resistance of dual-phase steel plates are suitable for tires, crawlers and other components in construction machinery manufacturing.

Household appliances: The high strength and corrosion resistance of dual-phase steel plates are suitable for the fuselage, shell and other components in the manufacture of home appliances.

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Our CR500/780DP steel products adopt the most advanced production technology and strict quality control, which ensures the high quality and stability of the products. This product has excellent mechanical properties and heat treatment properties, and can meet customers’ requirements for high strength, high hardness and high wear resistance of various parts. In addition, our CR500/780DP steel products also have good weldability and machinability, which is convenient for customers to carry out secondary processing and assembly.

If you are looking for high-quality CR500/780DP steel products and need high-quality pre-sales, sales and after-sales services, I believe that our company is your best choice. Warmly welcome you to come to consult, negotiate and cooperate!