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S30408 vs 304 Stainless Steel: Differences Guide
- John
S30408 and 304 stainless steel are virtually identical in composition, with the main difference being the standards they follow. S30408 conforms to China’s GB/T 20878, while 304 adheres to the ASTM A240/AISI standard.
Keep reading! —Learn which grade suits your project, explore technical comparisons, and discover why SteelPro Group is your trusted supplier.
What Is S30408?
S30408 is a specific type of 304 stainless steel used in some regional or industry standards. It has the same composition and properties as 304, offering strong corrosion resistance and good mechanical strength. It is often used in automotive parts, kitchen sinks, and exhaust systems due to its weldability and ease of fabrication. With a yield strength of 205 MPa and tensile strength between 520 MPa and 680 MPa, S30408 provides similar performance to 304 stainless steel.
What Is 304 Stainless Steel?
304 stainless steel, also called AISI 304, is a highly corrosion-resistant material made with chromium and nickel. This combination gives it excellent resistance to rust and oxidation. It is easy to shape and form, which makes it popular in industries like food processing, medical devices, and kitchen appliances. Its robustness and resilience make it ideal for uses that demand both cleanliness and extended durability.
S30408 | 304 | S30400 | 06Cr19Ni10 Specifications
| Grade | UNS code | Standards | Country/Region |
| 304 | S30400 | ASTM A240M-15a | American |
| 06Cr19Ni10 | S30408 | GB/T24511, GB/T 20878 | China |
| SUS304 | – | JISG4305:2012 | Japanese |
| 1.4301 | – | EN10028-7:2016 | Europe |
S30408 and 304 Stainless Steel Key Differences Overview
The distinctions between S30408 and 304 steel are minimal. Both grades offer similar corrosion resistance and mechanical properties.
The key distinction lies in S30408 having a lower carbon content and slightly higher nickel content, which can enhance its performance in specific conditions, such as higher temperatures.
Nonetheless, these distinctions are not substantial enough to significantly impact their general uses.
| Feature | S30408 | 304 Stainless Steel |
| Standard | GB/T 20878 | ASTM A240 / AISI 304 |
| Carbon Content | Lower carbon content (≤0.06%) | Higher carbon content (up to 0.08%) |
| Corrosion Resistance | Improved corrosion resistance due to higher nickel | Excellent corrosion resistance |
| Mechanical Properties | Better strength and high-temperature performance | Standard strength and temperature performance |
| Weldability | Better weldability due to higher nickel content | Good weldability |
| Applications | Suitable for harsher environments, high-temperature applications | General-purpose applications (e.g., food, medical) |
| Cost | Slightly higher due to specific formulation | Relatively lower, more common |
Corrosion Resistance
S30408 has slightly better corrosion resistance than 304 due to:
- Lower Carbon Content (≤0.07% vs. ≤0.08%), reducing intergranular corrosion risk after welding.
- Higher Chromium Content (18-20% vs. 17.5-19.5%), enhancing passivation layer stability.
- Higher Silicon Content (≤1.00% vs. ≤0.75%), improving high-temperature oxidation resistance.
Weldability
Both S30408 and 304 Stainless Steel are easy to weld, but with small differences:
- S30408: The lower carbon content (≤0.07%) reduces the risk of sensitization, requiring no additional heat treatment post-welding to maintain corrosion resistance.
- 304 Stainless Steel: The slightly higher carbon content (≤0.08%) may require control of heat input or post-weld treatments like pickling, especially for thicker sections.
S30408 vs 304 Stainless Steel: Chemical Composition
| Element | S30408 (GB/T 20878) | 304 (S30400, ASTM) | 304L (S30403, ASTM) |
| Carbon (C) | ≤ 0.07% | ≤ 0.08% | ≤ 0.03% |
| Chromium (Cr) | 18.00–20.00% | 17.5–19.5% | 17.5–19.5% |
| Nickel (Ni) | 8.00–11.00% | 8.0–10.5% | 8.0–12.0% |
| Manganese (Mn) | ≤ 2.00% | ≤ 2.00% | ≤ 2.00% |
| Silicon (Si) | ≤ 1.00% | ≤ 0.75% | ≤ 0.75% |
| Phosphorus (P) | ≤ 0.045% | ≤ 0.045% | ≤ 0.045% |
| Sulfur (S) | ≤ 0.030% | ≤ 0.030% | ≤ 0.030% |
| Nitrogen (N) | ≤ 0.10% | ≤ 0.10% | ≤ 0.10% |
S30408 vs 304 Stainless Steel: Mechanical Properties
- The hardness limit of ASTM 304 (≤201 HBW) is slightly higher than that of S30408 (≤187 HBW). However, both are in the annealed condition, making them ideal for cold working.
| Property | S30408 Steel | 304 Stainless Steel |
| Tensile Strength | ≥520 MPa (75 ksi) | ≥515 MPa (75 ksi) |
| Yield Strength | ≥205 MPa (30 ksi) | ≥205 MPa (30 ksi) |
| Elongation | ≥40% | ≥40% |
| Hardness | ≤187 HBW | ≤201 HBW |
| Modulus of Elasticity | ~193 GPa (28 × 10⁶ psi) | ~193 GPa (28 × 10⁶ psi) |
S30408 vs 304 Stainless Steel: Physical Properties
The physical properties of S30408 are identical to those of ASTM 304. Both grades maintain the core 18/8 (Cr/Ni) austenitic structure, resulting in comparable performance characteristics.
| Property | Value (Imperial) | Value (Metric) |
| Melting Point | 2552~2650°F | 1398~1454°C |
| Specific Heat Capacity | 0.5 kJ/(kg·K) | 0.5 kJ/(kg·K) |
| Thermal Conductivity (212°F/100°C) | 10.7 BTU/(hr·ft·°F·in) | 16.3 W/(m·K) |
| Thermal Conductivity (932°F/500°C) | 15.5 BTU/(hr·ft·°F·in) | 21.5 W/(m·K) |
| Linear Expansion Coefficient | 9.6 × 10⁻⁶/°F | 17.2 × 10⁻⁶/K |
| Electrical Resistivity (68°F/20°C) | 14.0 μΩ·in | 18.4 μΩ·mm²/m |
| Longitudinal Elastic Modulus (68°F/20°C) | 10539 ksi | 193 kN/mm² |
S30408 vs 304 Stainless Steel: Applications
Both S30408 and 304 stainless steel are austenitic stainless steels with near-identical corrosion resistance, formability, and weldability. They are widely used in:
- Food & Beverage Industry: Tanks, piping, conveyor systems, and cookware
- Architectural & Construction: Structural components, façades, handrails, and roofing.
- Chemical Processing: Storage tanks, valves, and pipes for mild corrosive chemicals.
- Medical Devices: Surgical tools, trays, and MRI-compatible equipment.
S30408 Steel Products Dimension
SteelPro Group ensures that all S30408 stainless steel products meet high-quality standards. We offer S30408 stainless steel products in various dimensions, including sheets, plates, and seamless tubes.
| Product | Dimension (Metric) | Dimension (Imperial) |
| Sheets/Plates | Thickness: 0.5 mm – 100 mm | Thickness: 0.02 in – 4 in |
| Width: 100 mm – 2000 mm | Width: 4 in – 79 in | |
| Length: 1000 mm – 6000 mm | Length: 39 in – 236 in | |
| Seamless Tubes | Outer Diameter: 6 mm – 120 mm | Outer Diameter: 0.24 in – 4.7 in |
| Wall Thickness: 0.5 mm – 20 mm | Wall Thickness: 0.02 in – 0.79 in | |
| Length: 1000 mm – 12000 mm | Length: 39 in – 472 in |
Your Trusted Supplier for S30408 and 304 Stainless Steel
When precision and durability matter, choose S30408 or 304 stainless steel from SteelPro Group. We provide a diverse selection of sizes, including sheets, plates, and seamless tubes.
We also provide other stainless steel products like 304L plates and 304H plates. With our expertise and high standards, you can count on reliable service and on-time delivery.
