Galvanized steel plates
Galvanized steel plates
Looking for the exact percent chemical composition of S350GD steel per EN 10346? You've come to the right place. As a direct steel factory with strict EN 10346 compliance, GNEE Steel supplies S350GD galvanized steel plates with transparent, standardized chemical ratios. In this guide, we'll break down each element's percentage, its role in performance, and how we ensure consistency-critical for your structural project's safety.
Galvanized steel is steel coated with zinc for corrosion resistance, available in grades like DX51D (general-use), S320GD (medium-strength), and S350GD (high-strength). S350GD, defined by EN 10346, is a structural grade with ≥350MPa yield strength, widely used in construction beams, automotive chassis, and machinery frames.
Its chemical composition directly determines strength, weldability, and formability. Every element's percentage is strictly controlled under EN 10346-deviations can lead to structural failure or poor processing, which is why GNEE Steel tests every batch for compliance.
EN 10346 Standard Percent Chemical Composition of S350GD Steel
EN 10346 specifies strict percentage ranges for each element in S350GD steel to ensure consistent performance. The table below details the standard requirements and GNEE Steel's typical values (tested per batch):
| Element | EN 10346 Standard (%) | GNEE Steel Typical (%) | Test Method |
|---|---|---|---|
| Carbon (C) | ≤0.12 | 0.08-0.11 | EN ISO 15350 |
| Manganese (Mn) | ≤1.60 | 1.20-1.50 | EN ISO 15350 |
| Phosphorus (P) | ≤0.035 | 0.020-0.030 | EN ISO 15350 |
| Sulfur (S) | ≤0.030 | 0.010-0.020 | EN ISO 15350 |
| Silicon (Si) | ≤0.50 | 0.20-0.40 | EN ISO 15350 |
| Aluminum (Al) | ≥0.020 | 0.025-0.050 | EN ISO 15350 |
| Iron (Fe) | Balance | 97.80-98.40 | Calculated |
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Key Compliance Note:
All our S350GD galvanized steel plates come with a mill test certificate (MTC) that lists the actual chemical percentages of the batch-ensuring traceability and alignment with your project's EN 10346 requirements.
Role of Each Element's Percentage in S350GD Performance
Every element's percentage in S350GD steel serves a specific purpose, directly impacting its mechanical properties and usability:
1. Carbon (C): ≤0.12% – Strength Foundation
Why this percentage: Carbon forms strong bonds with iron to boost yield strength (critical for S350GD's ≥350MPa requirement). Capping at 0.12% prevents excessive brittleness, which would make the steel crack during cold forming (e.g., bending beams).
Impact on use: Ensures S350GD can handle structural loads without sacrificing processability-essential for construction and automotive parts.
2. Manganese (Mn): ≤1.60% – Toughness Enhancer
Why this percentage: Manganese improves tensile strength and toughness (helping S350GD resist impacts from storms or road vibrations). Limiting to 1.60% avoids reducing weldability-higher Mn levels can cause cracks in welded joints.
Impact on use: Our typical 1.20-1.50% Mn range delivers the perfect balance of strength and weldability for heavy-duty components.
3. Phosphorus (P) & Sulfur (S): Minimized for Reliability
Why low percentages: Both are impurities. P (≤0.035%) causes cold brittleness (risk of cracking in low temperatures), while S (≤0.030%) leads to "hot shortness" (cracking during welding). Our lower typical values (P: 0.020-0.030%, S: 0.010-0.020%) reduce these risks.
Impact on use: Ensures S350GD performs reliably in harsh environments, from freezing winters to industrial welding processes.
4. Silicon (Si): ≤0.50% – Strength & Coating Helper
Why this percentage: Silicon enhances strength and improves zinc coating adhesion (key for galvanized steel). Limiting to 0.50% avoids reducing formability-too much Si makes the steel hard to stamp into complex shapes.
Impact on use: Our 0.20-0.40% Si range ensures the zinc coating doesn't peel, extending the service life of S350GD galvanized steel plates.
5. Aluminum (Al): ≥0.020% – Grain Refiner
Why this percentage: Aluminum refines the steel's grain structure, making mechanical properties (strength, elongation) uniform across the plate. Our 0.025-0.050% range ensures smaller grains for better toughness.
Impact on use: Guarantees every part of the S350GD plate performs the same-critical for large structural components like roof trusses.
How Chemical Percentages Affect S350GD's Mechanical Properties
The precise chemical percentages of S350GD steel directly translate to its mechanical performance. The table below links element ratios to key properties (using GNEE Steel's typical values):
| Mechanical Property | EN 10346 Requirement | Key Elements Influencing It | How Percentages Contribute |
|---|---|---|---|
| Yield Strength | ≥350MPa | C (0.08-0.11%), Mn (1.20-1.50%) | C and Mn form strong bonds to exceed the 350MPa minimum |
| Tensile Strength | 410-550MPa | Mn (1.20-1.50%) | Mn boosts tensile capacity to 420-540MPa (our typical range) |
| Elongation | ≥17% | P (0.020-0.030%), Al (0.025-0.050%) | Low P reduces brittleness; Al refines grains for 18-22% elongation |
| Impact Energy (0℃) | ≥27J | P (0.020-0.030%) | Low P avoids cold brittleness, delivering ≥30J impact energy |
S350GD Chemical Composition vs. Other EN 10346 Grades
Comparing S350GD's chemical percentages to other EN 10346 grades shows why it's ideal for high-strength needs:
| Element | S350GD (%) | S320GD (%) | DX51D (%) | Key Difference |
|---|---|---|---|---|
| C | ≤0.12 | ≤0.12 | ≤0.12 | Same C content; strength gap comes from Mn |
| Mn | ≤1.60 | ≤1.40 | ≤0.60 | S350GD has highest Mn for maximum strength |
| P | ≤0.035 | ≤0.035 | ≤0.045 | S350GD/S320GD have lower P for better low-temp performance |
| S | ≤0.030 | ≤0.030 | ≤0.045 | S350GD/S320GD have lower S for better weldability |
| Si | ≤0.50 | ≤0.50 | ≤0.10 | S350GD/S320GD have higher Si for coating adhesion |
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Key Takeaway:
S350GD's higher Mn percentage (vs. S320GD/DX51D) is the main reason for its superior yield strength-making it the top choice for load-bearing structural projects.
The percent chemical composition of S350GD galvanized steel per EN 10346 is carefully engineered to balance strength, weldability, and formability. GNEE Steel's strict control of each element's ratio ensures every batch meets or exceeds standard requirements, delivering reliable performance for your construction, automotive, or machinery project.
If you need to verify the chemical composition of S350GD for your project, or require a custom batch with adjusted ratios (where EN 10346 allows), our team is ready to assist. Contact GNEE Steel now to request a sample MTC, get a quotation for S350GD galvanized steel plates, or discuss your specific chemical composition needs!
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