CR700/980DHD+Z is a high ductility duplex steel galvanized coil. The microstructure of this steel consists of two phases: a soft, ductile ferrite phase and a hard, strong martensitic phase. Duplex microstructures are achieved through careful control of steel composition and processing, such as by adding alloying elements and using precise heat treatment processes.

CR700/980DHD+Z steel has high yield strength and tensile strength and is suitable for structural and automotive applications that require high strength and good formability. The dual-phase microstructure also provides excellent ductility, meaning the steel can deform significantly before breaking. This is important for applications where steel needs to be formed or bent without cracking or breaking, such as the manufacture of complex automotive parts.

What are the characteristics of CR700/980DHD+Z galvanized coil?

CR700/980DHD+Z Galvanized Coil is a High Strength Low Alloy (HSLA) steel coil that has been galvanized to provide corrosion resistance. Some of the features of CR700/980DHD+Z Galvanized Coil include:

High strength: CR700/980DHD+Z galvanized coil has a very high strength-to-weight ratio, making it an ideal material for lightweight structures and components.

Good ductility: Despite its high strength, CR700/980DHD+Z galvanized coil is ductile, which means it can be bent or formed without cracking or breaking.

Excellent Formability: This steel coil has excellent formability and can be easily formed into complex shapes and components.

Excellent Corrosion Resistance: The galvanized layer of CR700/980DHD+Z galvanized coil has excellent corrosion resistance, making it ideal for use in harsh environments.

Good surface quality: CR700/980DHD+Z galvanized coil has a smooth and uniform surface, easy to paint or other coatings.

What is the chemical composition of CR700/980DHD+Z galvanized coil?

CR700/980DHD+Z steel is also called hot-dip galvanized dual-phase steel, and its chemical composition is as follows:

Carbon (C): 0.14% max

Silicon (Si): 0.50% max

Manganese (Mn): 2.0% max

Phosphorus (P): 0.030% max

Sulfur (S): 0.020% max

Aluminum (Al): 0.015% minimum

Titanium (Ti): 0.15% max

Niobium (Nb): 0.09% max

Vanadium (V): 0.12% max

In addition to these elements, CR700/980DHD+Z steel also contains trace amounts of copper (Cu), chromium (Cr), nickel (Ni) and other elements. The exact composition may vary depending on the manufacturing process and specific application requirements. The steel is also coated with a layer of zinc (Z) to provide corrosion resistance.

What are the mechanical properties of CR700/980DHD+Z galvanized coil?

CR700/980DHD+Z steel is a dual-phase high-strength steel whose mechanical properties depend on various factors such as chemical composition, heat treatment, and manufacturing process. The following are some typical mechanical properties of this steel grade:

Tensile strength: 700-900 MPa

Yield strength: 980 MPa (minimum)

Elongation: 10-20%

Hardness: 230-280 HBW

Young’s modulus: 200 GPa

Note that these values are for general guidance only and may vary depending on specific production methods and other factors. The mechanical properties of CR700/980DHD+Z steel make it suitable for applications requiring high strength, good formability and excellent weldability, such as structural components such as chassis and suspension systems in the automotive industry.

What is the density of CR700/980DHD+Z galvanized coil?

The density of CR700/980DHD+Z galvanized coil will vary slightly depending on its exact composition, but is typically around 7.85 g/cm³ (or 0.2835 lb/in³). This is the same density as regular carbon steel, since the main difference between HSLA steel and regular carbon steel is their alloying elements and microstructure, not their density.

It should be noted that the density of CR700/980DHD+Z galvanized coil may be affected by its zinc coating, which has a density of approximately 7.13 g/cm³ (or 0.257 lb/in³). However, the thickness of the galvanized layer is usually much lower than the thickness of the steel itself, so it has relatively little effect on the overall density of the material.

What is the process of CR700/980DHD+Z galvanized coil?

CR700/980DHD+Z steel is usually produced by hot-dip galvanizing process. The technological process of producing CR700/980DHD+Z steel can be decomposed into the following steps:

Steelmaking: The first step in the process is to produce the steel itself. This is usually done using a basic oxygen furnace or an electric arc furnace. The steel is then cast into slabs or coils.

Hot rolling: The steel is then hot rolled to reduce its thickness and form it into the desired shape, such as a coil.

Pickling: After hot rolling, the steel is pickled to remove scale or oxides that may have formed on the surface during hot rolling. This is usually done using an acid solution.

Cold rolling: The pickled steel is cold rolled to further reduce its thickness and improve its surface finish.

Annealing: The steel is then annealed to relieve any stresses that may have been introduced during cold rolling.

Galvanizing: The steel is then coated with a layer of zinc using the hot-dip galvanizing process. In this process, the steel is passed through a bath of molten zinc, which metallurgically bonds to the steel surface, forming a protective layer of zinc.

Coiling: Finally, the galvanized steel is coiled and ready to be shipped to the customer.

What is the welding performance of CR700/980DHD+Z galvanized coil?

The welding performance of CR700/980DHD+Z galvanized coil will be affected by the galvanized layer on the steel surface. When welding galvanized steel, the heat of the welding process can cause the zinc to evaporate and produce noxious fumes and slag. Galvanized layers can also interfere with the welding process and reduce weld quality.

To overcome these challenges, certain precautions are recommended when welding CR700/980DHD+Z galvanized coils. These precautions include:

Proper Ventilation: Welding fumes from galvanized coatings may be harmful if inhaled. Therefore, it is very important to ensure that the welding area is adequately ventilated.

Pre-cleaning: Before welding, the galvanized layer on the part to be welded should be removed to reduce the volatilization of zinc during welding. This can be done mechanically or using solvents.

Appropriate welding technology: Welding CR700/980DHD+Z galvanized coil requires appropriate welding technology, such as using low heat input, controlling welding speed, selecting appropriate filler materials, etc.

Post-weld treatment: The weld seam should be cleaned after welding to remove possible zinc slag. It is also recommended to apply a coating or paint to the welds for additional protection against corrosion.

Will CR700/980DHD+Z galvanized coil rust?

While CR700/980DHD+Z Galvanized Coil is highly resistant to rust and corrosion, it is not completely immune. Zinc coatings on steel can degrade or become damaged over time, exposing the underlying steel to the environment. This can cause the steel to rust or corrode. However, the rate of corrosion is much slower than that of uncoated steel, and the degree of corrosion is usually not too severe. The performance of CR700/980DHD+Z galvanized coil in terms of rust and corrosion resistance depends on many factors, including the quality of the galvanizing process, the thickness of the galvanized layer, and the severity of the environment to which it is exposed. Proper handling, storage and maintenance of galvanized coil will also help extend its life and minimize the risk of rust or corrosion.

What are the applications of CR700/980DHD+Z galvanized coils in passenger cars?

CR700/980DHD+Z steel is widely used in the automotive industry, especially passenger cars, for its high strength, formability and weldability. Here are some common applications of this steel grade in passenger cars:

Chassis: CR700/980DHD+Z steel has high strength and good fatigue resistance, and is often used in the chassis and frame of passenger cars. Using this type of steel contributes to the durability and safety of the vehicle.

Suspension system: CR700/980DHD+Z steel is also used in the suspension system of passenger cars, such as control arms and stabilizer bars. This helps improve the handling and stability of the vehicle.

Body panels: CR700/980DHD+Z steel is used for various body panels of passenger cars, such as door frames, floor panels, columns, etc. Its excellent formability and weldability make it easy to fabricate and assemble into complex shapes and geometries.

Safety components: CR700/980DHD+Z steel is used in various safety components of passenger cars, such as door anti-collision beams, seat frames, roof reinforcements, etc. Its high strength contributes to a vehicle’s crashworthiness.