DX51D+Z Hot-Dip Galvanized Steel Sheet Features
DX51D+Z galvanized steel sheet is manufactured by immersing cold-rolled steel into a molten zinc bath, forming a protective zinc layer on the surface.
The most common method is continuous hot-dip galvanizing, where a steel coil passes through the molten zinc bath continuously, resulting in a uniform galvanized coating.
For alloy-coated galvanized steel, after dipping in zinc, the steel is heated to approximately 500℃, forming a zinc-iron alloy layer. This process improves coating adhesion, corrosion resistance, and weldability, making DX51D+Z suitable for construction, automotive, and appliance applications.
Specifications of DX51D+Z Galvanized Steel Sheet
| Cold-Rolled Thickness | Galvanized Thickness | Wear/Corrosion Plate | Galvanized Coil | Stainless Steel | Thick Plate |
|---|---|---|---|---|---|
| 0.1 mm | 0.1 mm | 1.5 mm | 0.1 mm | 0.1 mm | 1.5 mm |
| 0.2 mm | 0.2 mm | 2.0 mm | 0.2 mm | 0.2 mm | 2.0 mm |
| 0.3 mm | 0.3 mm | 2.5 mm | 0.3 mm | 0.3 mm | 2.5 mm |
| … | … | … | … | … | … |
| 5.0 mm | 5.0 mm | 16 mm | 5.0 mm | 5.0 mm | 16 mm |
Notes: DX51D+Z steel sheet thickness ranges from 0.1 mm to 5.0 mm, and it can be customized for galvanized coils, wear plates, corrosion-resistant plates, and stainless steel composites.
Chemical Composition
| Grade | C | Mn | Si | P | S | Cr | Ti | Nb | V |
|---|---|---|---|---|---|---|---|---|---|
| DX51D+AZ | Max: 0.43% | 0.13% | 0.03% | 0.01% | 0.01% | – | – | – | – |
| DX53D+AS | Max: 0.00% | 0.13% | 0 | 0.01% | 0.006 | – | 0.06% | – | – |
| DC01 | Max: 4.2 | 17 | 0.3 | 19 | 8 | – | – | – | – |
| SGCC | Max: 5 | 16 | 1 | 13 | 17 | – | – | – | – |
| Q235B | Max: 2 | 2 | 2 | 3 | 3 | – | – | – | – |
| Q345B | Max: 2 | 3 | 3 | 3 | 3 | 2 | – | 2 | – |
DX51D+Z steel sheet maintains low carbon content for excellent formability while providing sufficient manganese and aluminum to enhance strength and coating adhesion.
Processing Advantages of DX51D+Z and Al-Zn Coated Steel
High Thermal Reflectivity
Aluminum-zinc coated steel exhibits thermal reflectivity approximately twice that of standard galvanized steel, making it ideal for insulation panels and heat-reflective applications.
Heat Resistance
Al-Zn alloyed steel withstands temperatures over 300℃, with oxidation resistance similar to aluminum plating. Typical applications include chimney tubes, ovens, solar lamp shades, and high-temperature industrial equipment.
Superior Corrosion Resistance
The aluminum content forms a dense aluminum oxide layer as zinc wears off, protecting the steel substrate and prolonging the service life of DX51D+Z galvanized steel.
Cost Efficiency
With a lower density (55% Al-Zn), aluminized zinc steel offers 3% more coverage area than traditional zinc coatings under the same weight and thickness, reducing material cost for large surface projects.
Excellent Paintability
Al-Zn coated DX51D+Z can be painted directly without pre-treatment. It provides strong adhesion for coatings, suitable for advertising boards, building panels, and appliance enclosures.
Aesthetic Silver-White Surface
Al-Zn steel offers an attractive bright, uniform finish, enhancing visual appeal for architectural and consumer applications.
Processing Performance
DX51D+Z and Al-Zn coated steel retain similar stamping, forming, and spraying properties as traditional galvanized steel, ensuring compatibility with common fabrication techniques.
Applications of DX51D+Z Galvanized Steel Sheet
Roofing and siding panels for residential and industrial buildings
Household appliance housings and electrical enclosures
Ventilation ducts and light structural components
Automotive parts where corrosion resistance and formability are critical
Q1: What does the designation "DX51D+Z" mean?
A: This is a standard European (EN) designation for a hot-dip galvanized steel grade:
DX: Indicates it is a forming steel primarily for cold forming applications.
51: A numerical designator specifying a base steel with a minimum yield strength typically ≤ 280 MPa and specific mechanical properties suitable for forming.
D: Denotes the ductility level. "D" stands for "Drawing" quality, indicating good to very good ductility for deep drawing applications.
+Z: Specifies the coating: hot-dip galvanized with a zinc coating.
Q2: What are its primary mechanical properties?
A: According to EN 10346, the typical properties are:
Yield Strength (Re): Usually 140 - 300 MPa (Note: No specific minimum is mandated; it's based on the base steel chemistry for formability).
Tensile Strength (Rm): 270 - 500 MPa.
Elongation (A₈₀): Typically ≥ 22% - 26% (minimum depends on thickness). This high elongation is key for its formability.
It is not a high-strength steel. Its value lies in its excellent formability and corrosion protection.
Q3: What is the "Z" coating, and what are typical coating weights?
A: The "Z" stands for a massive zinc coating applied via the continuous hot-dip galvanizing process. The coating weight is specified by a suffix (e.g., Z140, Z275):
Example - DX51D+Z140: Minimum total coating mass of 140 g/m² (approx. 20 µm per side, 40 µm total). Common codes are Z100 (light), Z140 (standard), Z200/Z225 (heavy), and Z275 (extra heavy for severe environments).
Q4: What are the main applications for DX51D+Z?
A: It is the workhorse steel for general fabrication where corrosion resistance and formability are needed, but not high structural strength. Common uses include:
HVAC ductwork and components.
Appliance housings (washing machines, dryers, enclosures).
Light gauge building panels and profiles.
General metal cabinets, enclosures, and light furniture.
Agricultural and industrial containers.