Equivalent Materials

Martensitic Stainless Steel Grade Equivalents

What is the EN equivalent of AISI 304 stainless steel?

The EN equivalent of AISI 304 stainless steel is EN 1.4301 (designation X5CrNi18-10). In the DIN system, this is also known as Werkstoff Nr. 1.4301. The Japanese equivalent is SUS304, and the Chinese GB equivalent is 06Cr19Ni10 (formerly 0Cr18Ni9). All these designations refer to the same grade with approximately 18% chromium and 8% nickel content.

What is the Chinese GB equivalent of AISI 316 stainless steel?

The Chinese GB equivalent of AISI 316 stainless steel is 06Cr17Ni12Mo2 (old designation: 0Cr17Ni12Mo2). For 316L, the GB equivalent is 022Cr17Ni12Mo2 (old designation: 00Cr17Ni12Mo2). The EN equivalents are 1.4401 for 316 and 1.4404 for 316L. The Japanese JIS designations are SUS316 and SUS316L respectively.

Is SUS304 the same as AISI 304?

Yes, SUS304 is the JIS (Japanese Industrial Standards) designation for the same grade as AISI 304. The "SUS" prefix stands for "Steel Use Stainless" in the JIS naming system. Both designations have the same chemical composition (approximately 18% chromium, 8% nickel, ≤0.08% carbon) and the same UNS number S30400. They are fully interchangeable in material specifications.

What is the DIN number for 316L stainless steel?

The DIN Werkstoff number for 316L stainless steel is 1.4404 (designation X2CrNiMo17-12-2). Since DIN stainless steel standards have been largely superseded by EN standards (EN 10088 series), this is also the EN number. An alternative EN number 1.4435 (X2CrNiMo18-14-3) is also sometimes referenced for 316L with slightly different composition ranges.

Are stainless steel grades from different standards exactly identical?

No. Equivalent grades from different standards have similar but not necessarily identical chemical compositions and mechanical properties. Allowable ranges for elements like carbon, chromium, nickel, and molybdenum may differ slightly between ASTM, EN, JIS, and GB standards. For example, the chromium range for "304" might be 18.0–20.0% in ASTM but 17.5–19.5% in EN. For critical applications, always verify the exact composition limits against the official standard document and confirm with your supplier.

What does the "L" suffix mean in stainless steel grades like 304L and 316L?

The "L" in 304L and 316L stands for "Low Carbon." These grades have a maximum carbon content of 0.03% (compared to 0.08% in standard 304 and 316). The reduced carbon content minimizes carbide precipitation (sensitization) during welding, which can cause intergranular corrosion in the heat-affected zone. This makes L-grades the preferred choice for welded components and large-gauge constructions. The trade-off is slightly lower tensile and yield strength compared to the standard grades.