uns S41500 equivalent JIS SUSF415 stainless

UNS S41500 Equivalent: JIS SUSF415 Stainless

Published: November 7, 2025 | Updated: November 7, 2025By Gangsteel Engineering Team – 25+ Years in Stainless Steel Export Excellence

UNS S41500 is a martensitic stainless steel recognized for its high strength, good toughness, and moderate corrosion resistance, commonly used in applications like pressure vessels, valves, and offshore equipment. Often known as F6NM or AISI 415, this grade's low-carbon design makes it heat-treatable and suitable for sour service environments. A frequent query in international sourcing is its equivalence to JIS SUSF415, the Japanese standard for a similar soft martensitic steel. As a leading producer and exporter in China, Gangsteel has supplied thousands of tons of UNS S41500 with dual certifications to JIS equivalents, enabling cost-effective swaps for clients bridging U.S. and Japanese specs. This guide confirms the equivalence, compares properties, and offers practical advice, based on industry standards and our mill data.

From our 2024 exports to Japanese petrochemical plants, clients used UNS S41500 as an equivalent to JIS SUSF415 in reactor components, achieving identical performance in H2S environments without re-qualification, saving 15-20% on testing costs. Yes, UNS S41500 is directly equivalent to JIS SUSF415, with overlapping chemistry, mechanical properties, and applications under ASTM A240 and JIS G 4303/G 4315. Minor differences in Mo/Ni ranges don't impact equivalence for most uses, and density remains 7.85 g/cm³ for both. Let's compare in detail.

Why UNS S41500 and JIS SUSF415 Are Equivalent

UNS S41500 (U.S. ASTM) and JIS SUSF415 (Japanese JIS) are equivalent soft martensitic steels, sharing a 13Cr-4Ni-Mo composition for high strength (yield ~620 MPa) and toughness while maintaining weldability. This equivalence stems from similar low-carbon bases to avoid brittleness, with Cr for passivation, Ni for austenite stability, and Mo for pitting resistance (PREN 18-22). Equivalence allows direct substitution in plates under A240 and JIS G 4303, with heat treatment yielding comparable hardness (<32 HRB) and impact (27 J at -18°C). For NACE sour service, both comply when hardness is controlled. Gangsteel's dual-certified stock (1-200mm thick) has facilitated swaps, priced at $2,600-2,800/ton FOB.

Property Comparison: UNS S41500 vs. JIS SUSF415

The grades are equivalent in density (7.85 g/cm³), PREN (18-22), and performance, with minor range differences.

Chemical Composition (% by Weight)

Equivalence holds as differences are within tolerance.

Mechanical Properties (Tempered Min Values)

Corrosion and Other Properties

• PREN: 18-22 for both – Good in chlorides/H2S.
• Density: 7.85 g/cm³ – Identical.
• Weldability: Both excellent with E410NiMo; PWHT at 620°C.

Applications: Shared for Equivalents

Both suit sour valves, petrochemical reactors, marine risers, power turbines. Gangsteel's dual-cert stock has supported hybrid U.S./Japanese projects.

Sourcing: Practical Advice

Gangsteel offers UNS S41500 / JIS SUSF415 plates at $2,600-2,800/ton FOB, 1-200mm thick. Dual certs save on testing; contact for quotes.

FAQ: S41500 and SUSF415 Equivalence Questions Answered

Q: Is UNS S41500 equivalent to JIS SUSF415 stainless?

A: Yes, UNS S41500 is directly equivalent to JIS SUSF415, with similar chemistry, mechanical properties, and applications for high interchangeability.

Q: What are the differences between UNS S41500 and JIS SUSF415?

A: Minor: JIS SUSF415 has slightly higher Si max (1.00% vs. 0.60%) and P max (0.040% vs. 0.030%), but PREN (18-20 vs. 18-22) and mechanicals (yield 620 MPa) are comparable for equivalence.

Q: Can I substitute JIS SUSF415 for UNS S41500 in ASTM specs?

A: Yes, with high equivalence; dual-cert material from Gangsteel ensures compliance without issues.

Q: What standards cover S41500 and JIS SUSF415?

A: S41500 under ASTM A240/A182; JIS SUSF415 under JIS G 4303/G 4315. Equivalent for plates/forgings.

Q: Are there any limitations in equivalence between S41500 and JIS SUSF415?

A: Minor for corrosion-critical apps (slight differences in Si/P may affect minor properties); otherwise, fully equivalent.

Q: What is the density of S41500 and its equivalents?

A: 7.85 g/cm³ for both S41500 and JIS SUSF415—identical for weight calculations.

Q: Where can I source S41500 or JIS SUSF415?

A: Gangsteel stocks both at $2,600-2,800/ton FOB, 1-200mm thick. Dual certs available.

Q: Is S41500 equivalent to other grades like 410 or 316?

A: No—better than 410 in toughness/corrosion, but not as corrosion-resistant as 316; equivalents are specifically 13Cr-4Ni types like SUSF415.