SUS304 vs SS304 : which is better?
SUS304 and SS304 stainless steel are essentially the same 18/8 stainless steel alloy (18% chromium, 8% nickel). The only difference lies in regional naming conventions: SUS (Steel Use Stainless) is the Japanese/JIS standard, while SS (Stainless Steel) or AISI 304 is the American/international standard. Therefore, the choice of which stainless steel to use depends on the project location, not performance, as both offer excellent corrosion resistance and mechanical properties.
what is the meaning of sus304 stainless steel?
SUS304 stainless steel is a popular, versatile grade defined by Japanese Industrial Standards (JIS), essentially the Japanese equivalent of U.S. ASTM 304, known for its excellent corrosion resistance and durability due to its composition of about 18% chromium and 8% nickel (hence also called "18/8 stainless steel"). The "SUS" prefix stands for "Steel Use Stainless," indicating its application in various durable and hygienic products, from kitchenware to architectural components, often used in food, chemical, and medical fields.
What is 304 SS material?
Type 304 is the most versatile and widely used stainless steel. It is still sometimes referred to by its old name 18/8 which is derived from the nominal composition of type 304 being 18% chromium and 8% nickel. Type 304 stainless steel is an austenitic grade that can be severely deep drawn.
What is the equivalent standard of SUS304?
| Grade | Standard Source | Full Name | International Equivalent |
|---|---|---|---|
| SUS304 | Japanese Industrial Standard (JIS) | Steel Use Stainless 304 | AISI 304 (U.S. Standard) |
| SS304 | U.S./International Common Abbreviation | Stainless Steel 304 | EN 1.4301 (European Standard) |
Chemical compositions of SUS304 and SS 304
| Element | SUS304 (JIS) | SS304 (ASTM/EN) |
|---|---|---|
| Carbon (C) | ≤ 0.08% | ≤ 0.07% |
| Silicon (Si) | ≤ 1.00% | ≤ 0.75% |
| Manganese (Mn) | ≤ 2.00% | ≤ 2.00% |
| Phosphorus (P) | ≤ 0.045% | ≤ 0.045% |
| Sulfur (S) | ≤ 0.03% | ≤ 0.03% |
| Chromium (Cr) | 18.00–20.00% | 17.50–19.50% |
| Nickel (Ni) | 8.00–10.50% | 8.00–10.50% |
Physical properties of SUS304 and SS304
| Density | 7.8–8.2 g/cm³ |
| Melting Point | 1,230–1,480°C |
| Specific Heat | 440–500 J/kg·℃ |
| Electrical Resistivity | 7.3×10⁻⁷–8.5×10⁻⁷ Ω·m (at 20℃) |
| Coefficient of Thermal Expansion | 1.7×10⁻⁵–1.9×10⁻⁵ 1/K |
| Thermal Conductivity | 14–20 W/m·K |
SUS304 stainless steel corrosion resistance
It has excellent corrosion resistance to the atmosphere, water, weak acid and alkali (such as food processing environment), which is better than ordinary carbon steel. Through solution treatment (quenching at 1010-1150℃), intergranular chromium deficiency is eliminated to avoid welding corrosion.
SUS304 stainless steel processing performance
It has good ductility, is easy to stamp, bend and weld, and is suitable for complex shape manufacturing.
It is non-magnetic (it may be slightly magnetic after cold processing).
SUS304 stainless steel high temperature resistance
The short-term use temperature can reach 870℃, and the long-term working temperature is ≤538℃, which is better than 304L (low carbon version).
Which one is more expensive, SUS304 or SS304?
Neither SUS304 nor SS304 is inherently more expensive; they are essentially the same material (Type 304 stainless steel), just named under different standards (JIS for SUS, ASTM for SS), with cost variations depending on regional sourcing, specific supplier certifications, logistics, and current market prices, though sometimes SUS304 might see a slight premium in Asia for specialized quality.
What is the difference between SUS304 and SUS316 stainless steel?
SUS304 is the standard "18/8" stainless steel, offering good general corrosion resistance, while SUS316 adds molybdenum, giving it superior resistance to chlorides (like saltwater) and harsh chemicals, making it ideal for marine, medical, and chemical applications, though at a higher cost. Visually identical, the key difference is 316's enhanced corrosion protection due to molybdenum, making it better for demanding environments where 304 might corrode.
If you need to purchase cost-effective SUS304 or SS304 stainless steel plates/rolls, contact us now Email: es@gescosteel.com,Get a free quote! Support customized striping, film lamination, laser cutting, and provide 100% material certification and technical guidance.
