Galvanized Steel plate

Galvanized Steel Sheets: Premium Quality for Global Applications

1. Raw Material Composition: The Foundation of Quality

The superior performance of our galvanized steel sheets starts with carefully selected raw materials, designed to balance strength, formability, and corrosion protection:

• Base Steel: We use low-carbon steel (with a carbon content ≤0.12%) as the core material. This low-carbon composition ensures excellent formability, allowing the steel to be bent, cut and shaped without cracking—critical for applications like automotive body panels and construction components. The base steel also meets strict purity standards, with minimal impurities (such as sulfur and phosphorus) to prevent brittleness and enhance structural integrity.
• Zinc Coating: The protective layer is made of high-purity zinc (≥99.5% pure zinc). For specialized high-corrosion environments (e.g., coastal areas or industrial zones), we offer alloyed zinc coatings (e.g., Zn-Al-Mg alloys). These alloy coatings provide up to 50% better corrosion resistance than traditional pure zinc, extending the product’s service life by 3–5 years on average.
• Optional Additives: For specific applications (e.g., high-temperature or food-grade uses), we incorporate trace elements like silicon or chromium into the base steel or coating. These additives improve heat resistance, chemical stability, or compliance with food safety standards (e.g., FDA regulations for food processing equipment).

2. Manufacturing Process: Precision from Start to Finish

Our galvanized steel sheets are produced through a rigorous, automated process that ensures consistency and quality at every step. The key stages include:

1. Hot Rolling: Steel billets (heated to 1,200–1,300°C) are passed through a series of rolling mills to reduce thickness and form continuous steel coils. This step establishes the base steel’s initial strength and thickness (ranging from 2.0mm to 6.0mm for hot-rolled coils).
2. Cold Rolling: The hot-rolled coils undergo cold rolling at room temperature to refine thickness (down to 0.12mm for thin-gauge products) and improve surface smoothness. Cold rolling also enhances the steel’s tensile strength by up to 20% through work hardening.
3. Cleaning &Pickling: The cold-rolled steel is immersed in a hydrochloric acid solution to remove oxides, rust, and oil residues from the surface. This step is critical—any contaminants left on the steel would prevent proper adhesion of the zinc coating.
4. Hot-Dip Galvanizing: The cleaned steel is continuously dipped into a molten zinc bath (maintained at 440–460°C). As the steel exits the bath, a uniform zinc layer forms on its surface through a metallurgical reaction between zinc and iron. The thickness of the zinc coating is controlled by adjusting the speed of the steel’s exit from the bath (faster speeds = thinner coatings, slower speeds = thicker coatings).
5. Passivation Treatment: After galvanizing, the steel undergoes an optional passivation process (using chromate or non-chromate solutions). This forms a thin, invisible film on the zinc surface that prevents white rust (a common issue with fresh zinc coatings) during storage and transportation.
6. Skin Pass Rolling: The final step involves light rolling of the galvanized steel to improve flatness, reduce surface defects (e.g., dents), and create the desired surface finish (e.g., regular spangle, minimized spangle, or zero spangle).
7. Quality Inspection: Every coil is inspected for coating thickness (via magnetic induction testing), surface quality (using automated vision systems), and mechanical properties (tensile strength and elongation tests). Only products that meet our internal standards (and global regulatory requirements) are shipped to clients.

3. Specifications &Models: Tailored to Global Needs

Our galvanized steel sheets are available in a wide range of specifications to match the requirements of different regions and applications. Below is a detailed breakdown of key parameters:

3.1 Core Specifications

3.2 Global Standard Compliance

To ensure compatibility with regional regulations and project requirements, our galvanized steel sheets meet the following internationally recognized standards:

• China (GB/T 2518-2019):Covers grades from DX51D+Z (general use) to S550GD+Z (high-strength structural use). Zinc coating weights range from 40g/m²to 275g/m². Ideal for domestic Chinese projects, such as building facades and electrical cabinets.
• United States (ASTM A653/A653M-23):Includes grades like CS Type B (general construction), HSLAS H400 (medium-strength automotive), and AHSS Type 500 (high-strength safety components). Coating designations (G30–G140) align with North American corrosion requirements. Commonly used in HVAC ducts, trailer frames, and automotive parts.
• Europe (EN 10346:2015):Features grades such as DX51D+Z (entry-level) and HX420LAD+Z (high-formability automotive). Surface quality classes (A–D) ensure consistency for high-end applications like automotive outer panels. Compliant with CE marking requirements for EU markets.
• Japan (JIS G3302:2018):Offers grades including SGCC (general use) and SGCD3 (high-precision automotive). Spangle options (S = spangle, N = non-spangle) cater to Japanese manufacturing standards for appliances and motorcycles.
• Australia (AS/NZS 1397:2021):Focuses on high-strength grades like G300 (residential roofing) and G650 (heavy-duty industrial structures). Zinc coating levels (Z275, Z350) are optimized for Australia’s harsh UV and coastal environments.

4. Why Choose Our Galvanized Steel Sheets?

• 20 Years of Expertise: Our manufacturing processes are refined through decades of experience, ensuring consistent quality and reliability.
• Global Compatibility: Compliance with 5+ major international standards means our products integrate seamlessly into projects worldwide.
• Custom Solutions: We offer tailored specifications (thickness, coating, finish) to meet unique client needs—whether for a small construction project or large-scale automotive production.
• Quality Assurance: Every batch undergoes 10+ quality checks, from raw material testing to final coating inspection. We hold ISO 9001 certification and provide material test reports (MTRs) for all orders.

For more information on how our galvanized steel sheets can support your project, contact our sales team today. We offer fast lead times (7–14 days for standard orders) and global shipping to 50+ countries.

Galvanized Steel Sheet Specification Table (Global Standards)

1. Chinese National Standard (GB/T 2518-2019)

2. American Standard (ASTM A653/A653M-23)

3. European Standard (EN 10346:2015)

4. Japanese Standard (JIS G3302:2018)

5. Australian Standard (AS/NZS 1397:2021)