When selecting stainless steel plates for industrial applications, understanding the differences between grades is critical to ensure durability, corrosion resistance, and compliance with standards. S30408 and S30403 are two widely used austenitic stainless steel grades, often used in chemical, food, pharmaceutical, and construction industries.
What material is S30408 plate?
S30408 is a Chinese national standard (GB/T 20878) designation for 304 austenitic stainless steel. It is a versatile, chromium-nickel alloy (18/8) known for excellent corrosion resistance, high strength, good weldability, and easy fabrication, commonly used for pressure vessels, kitchen equipment, and chemical containers.
what is UNS S30403 plate specification ?
UNS S30403 (304L) stainless steel plate is a low-carbon 18-8 chromium-nickel austenitic stainless steel, primarily used for pressure vessels and general purposes according to ASTM A240/ASME SA240 standards. It offers excellent corrosion resistance and weldability, with a carbon content limited to ≤ 0.03%, thus preventing sensitization without the need for post-weld heat treatment.
Overview of S30408 and S30403
| Grade | Standard Designation | UNS Number | Type | Key Feature |
|---|---|---|---|---|
| S30408 | 1.4301 / 304 | S30408 | Austenitic | Standard 304, general-purpose stainless steel plate |
| S30403 | 1.4306 / 304L | S30403 | Austenitic, low-carbon | Low-carbon variant of 304, optimized for welding |
S30408 vs. S30403 Stainless Steel Plates: Chemical Composition
| Element | S30408 (%) | S30403 (%) | Note |
|---|---|---|---|
| Carbon (C) | ≤0.07 | ≤0.03 | Low carbon content in S30403 reduces carbide precipitation |
| Chromium (Cr) | 17.0–19.5 | 17.0–19.5 | Same corrosion resistance |
| Nickel (Ni) | 8.0–10.5 | 8.0–10.5 | Same austenitic structure |
| Manganese (Mn) | ≤2.0 | ≤2.0 | Similar |
| Silicon (Si) | ≤1.0 | ≤1.0 | Similar |
| Phosphorus (P) | ≤0.045 | ≤0.045 | Similar |
| Sulfur (S) | ≤0.03 | ≤0.03 | Similar |
| Nitrogen (N) | ≤0.11 | ≤0.11 | Similar |
S30408 vs. S30403 Stainless Steel Plates: Mechanical Properties
| Property | S30408 | S30403 | Note |
|---|---|---|---|
| Yield Strength | 205 MPa | 205 MPa | Similar load-bearing capacity |
| Tensile Strength | 500–700 MPa | 485–690 MPa | Slightly lower in S30403 due to low carbon |
| Elongation | ≥40% | ≥40% | Excellent ductility in both |
| Hardness | 70–95 HRB | 70–90 HRB | Similar |
| Max Service Temp | 870°C | 870°C | Both suitable for high-temp environments |
Applications of S30408 vs S30403 Plates
| Application Area | Recommended Grade | Reason |
|---|---|---|
| Chemical Tanks | S30403 | Low-carbon grade reduces intergranular corrosion during welding |
| Food & Beverage Equipment | Both | Both grades are corrosion-resistant; S30403 preferred if welding involved |
| Pressure Vessels | S30408 | Standard 304 plate provides sufficient strength |
| Marine Components | Both | Excellent resistance to atmospheric corrosion; S30403 preferred for welded marine structures |
| Structural Fabrication | S30403 | Low-carbon minimizes welding cracks and improves longevity |
Can S30408 and S30403 be welded?
Yes, both grades are weldable. However, S30403 is preferred for welded applications due to its low carbon content, which prevents carbide precipitation and reduces the risk of intergranular corrosion.
Which grade should I choose for high-temperature applications?
Both S30408 and S30403 can operate up to 870°C, but if welding is involved, S30403 is safer for maintaining corrosion resistance at elevated temperatures.
Why Choose Gnee Stainless Steel?
Gnee provides high-quality S30408 and S30403 stainless steel plate with:ISO, SGS, and BV certified products,Standard and custom sizes,Cutting, bending, and surface treatment services,Technical support and fast delivery
Call to Action:
Contact us today for a free quote or custom stainless steel plate solutions tailored to your industry needs.Mail:es@gescosteel.com
