DX51D and SGCC are commonly used steel grades for hot-dip galvanized steel products in construction, industrial manufacturing, and infrastructure. DX51D follows the EN 10346 standard, while SGCC follows JIS G 3302. This guide compares their mechanical properties, zinc coatings, corrosion resistance, and costs to help you choose the right material for your project.
Which Standards Define DX51D and SGCC?
- SGCC: Specified under JIS G 3302, the Japanese standard for hot-dip zinc-coated steel sheets and strips. It is commonly specified in Japan and parts of East and Southeast Asia. In the designation, SG identifies the standard’s galvanized steel product category, the first C indicates a cold-rolled base metal, and the final C denotes commercial quality. Therefore, SGCC refers to commercial-quality hot-dip galvanized steel with a cold-rolled base metal.
- DX51D: Specified under EN 10346, the European standard for continuously hot-dip-coated steel flat products. It is commonly specified in Europe and in export projects across the Middle East and Africa that require EN standards. In the DX51D designation, D refers to flat products for cold forming, X indicates that the rolling condition is unspecified, 51 identifies the steel grade, and the final D denotes a hot-dip-coated product.
Chemical Composition and Mechanical Properties
Chemical Composition
Unit: % by mass (maximum values for the base steel; zinc coating excluded). Values are based on the applicable standard requirements.
| Grade | Standard | C | Mn | P | S | Si | Ti |
| DX51D | EN 10346 | ≤0.18 | ≤1.20 | ≤0.12 | ≤0.045 | ≤0.50 | ≤0.30 |
| SGCC | JIS G 3302 | ≤0.15 | ≤0.80 | ≤0.05 | ≤0.05 | — | — |
Mechanical Properties
- DX51D: Offers good cold formability and bendability for bending, profiling, and general forming. Under EN 10346:2015, its tensile strength is 270–500 MPa, with a minimum A80 elongation of 22% for thicknesses above 0.7 mm. Lower elongation limits apply to thinner products.
- SGCC: Is a commercial-quality galvanized steel grade used for general sheet metal forming. Its mechanical properties should be verified against the applicable JIS G 3302 requirements and the agreed product specifications.
Coating Designations for DX51D and SGCC
- DX51D: Under EN 10346, DX51D may be supplied with different coating types, including +Z (zinc), +ZF (zinc-iron), +AZ (zinc-aluminium), +ZM (zinc-magnesium), and +AS (aluminium-silicon). Designations such as Z100, Z140, and Z275 indicate the nominal coating mass on both surfaces combined.
- SGCC: Under JIS G 3302, SGCC can be supplied with zinc or zinc-iron alloy coatings. Common coating-mass designations include Z12, Z18, and Z27 for zinc coatings, and F12 for zinc-iron alloy coatings, where applicable. These designations specify coating-mass requirements based on the total mass on both surfaces.
Durability and Surface Quality
Wanzhi Group supplies galvanized steel products in various specifications, with customized sizes and processing options for different metal fabrication needs. With proper coating selection and maintenance, galvanized steel may last 10 years or longer, depending on coating weight and service conditions.
DX51D is commonly used for general forming and cost-sensitive projects. SGCC may cost more when specific JIS compliance, coating, or surface requirements apply. Compared with 304 stainless steel, DX51D galvanized steel is generally more affordable, but its corrosion resistance and service life depend on the zinc coating and service environment.
DX51D and SGCC Galvanized Steel Applications
- Construction: Roofing sheets, wall cladding, ceiling panels, and building accessories.
- HVAC Systems: Ventilation ducts and air-conditioning components.
- Home Appliances: Washing machine housings, refrigerator panels, and appliance enclosures.
- Automotive: Non-structural covers and general sheet metal components.
- Metal Fabrication: Cabinets, electrical enclosures, cable trays, and formed parts.
Are DX51D and SGCC Equivalent?
DX51D and SGCC are not fully equivalent, but they may be interchangeable in some applications. Substitution is possible for general forming projects when mechanical properties, zinc coating weight, surface finish, and dimensional requirements meet the project specifications. For structural, demanding forming, or corrosive environments, verify material performance and customer requirements before substitution.
Common Galvanized Steel Grades Under Different Standards
Besides DX51D and SGCC, galvanized steel is available in various grades under EN, JIS, ASTM, and GB standards. These grades differ in formability and strength requirements. The following table lists common examples; availability depends on the applicable standard and product specifications.
| Standard | Common Steel Grades |
| EN 10346 | DX52D, DX53D, DX54D, DX56D, S220GD, S250GD, S280GD, S320GD, S350GD, S550GD |
| JIS G 3302 | SGCD1, SGCD2, SGCD3, SGC340, SGC400, SGC440, SGC490, SGC570 |
| ASTM A653/A653M | CS Type A, CS Type B, CS Type C, FS, DDS, EDDS, SS Grade 33, SS Grade 37, SS Grade 50, SS Grade 80 |
| GB/T 2518 | DX51D+Z, DX52D+Z, DX53D+Z, DX54D+Z, S250GD+Z, S350GD+Z, S550GD+Z |
What to Consider When Choosing DX51D or SGCC Galvanized Steel
- Steel Grade and Standard: Choose DX51D under EN 10346 or SGCC under JIS G 3302 according to project requirements.
- Strength and Formability: DX51D suits general forming. For more demanding bending or stamping, consider DX52D, DX53D, or other grades with suitable forming properties.
- Dimensions and Product Form: Confirm thickness, width, tolerances, and product form.
- Zinc Coating: Select the coating designation and mass according to the required corrosion protection. Ensure coating values are compared on the same basis.
- Surface Finish and Treatment: Specify the spangle type and surface treatment, such as passivation, oiling, phosphating, chromate treatment, or an untreated surface, based on storage, painting, and processing needs.
- Service Environment: Consider indoor or outdoor use, dry or humid conditions, coastal exposure, and corrosive pollutants when selecting the appropriate zinc coating and corrosion protection.
- Quality and Inspection: Confirm the availability of a Mill Test Certificate (MTC) and any required material, coating, and inspection tests.
- Order and Delivery: Check the minimum order quantity (MOQ), lead time, packaging, shipping terms, and delivery schedule.
China Galvanized Steel Manufacturer – Wanzhi Group
Wanzhi Group is an ISO-certified galvanized steel manufacturer and supplier in China. We offer DX51D and SGCC galvanized steel products in various forms, including galvanized coils, sheets, strips, pipes, and wires. Customized specifications are available upon request.
Our galvanized steel products can be supplied to applicable ASTM, EN, JIS, and GB standards. Original Mill Test Certificates (MTCs) are available, and third-party inspections by SGS, BV, TÜV, and other agencies can be arranged. Our products have been exported to over 120 countries and regions worldwide.
Feel free to contact Wanzhi Group with your requirements to get a free quote and a customized solution.
Factory Strength
Our factory is located in Boxing County, Binzhou, Shandong, China. It is equipped with two hot-dip galvanizing lines, three color coating lines, and a zinc-aluminum-magnesium (ZAM) steel production line. Each production line has a monthly capacity of up to 10,000 tons.
The factory features a 500 m² quality inspection center, along with a sample room, supporting strict quality inspection and control to ensure consistent product quality. We maintain over 20,000 tons of stock for prompt delivery. Customized orders typically require 5–45 working days.
If you are looking for a reliable steel supplier, Wanzhi Group is ready to support your projects. With 15 years of industry experience, we supply GI, GL, PPGI, PPGL, PPAL, stainless steel, and other steel products. Contact us for a tailored solution.