Categories: Blogs

UNS S39274 vs UNS S32760: Key Differences Explained

When selecting materials for harsh industrial environments, super duplex stainless steels like UNS S39274 and UNS S32760 stand out for their excellent corrosion resistance and high mechanical strength. Although these two grades are often used interchangeably, there are critical differences in chemical composition, mechanical performance, and application suitability that can impact long-term operational efficiency.

This guide offers a clear, side-by-side comparison of UNS S39274 vs UNS S32760, helping engineers and procurement teams choose the right alloy for their project needs.

Understanding Super Duplex Stainless Steels

Both UNS S39274 and UNS S32760 belong to the family of super duplex stainless steel grades, known for their dual-phase microstructure of austenite and ferrite. This composition enables high resistance to pitting, crevice corrosion, and stress corrosion cracking especially in chloride-rich or chemically aggressive environments.

Key Chemical Composition Differences

While both alloys offer a high resistance to corrosion, the variation in chemical elements affects their behavior in different applications. Here is the comparison table below:

ElementUNS S32760 (%)UNS S39274 (%)
Chromium24.0 – 26.025.0 – 27.0
Nickel6.0 – 8.06.0 – 8.0
Molybdenum3.0 – 4.03.5 – 4.5
Nitrogen0.2 – 0.3≤ 0.3
Copper0.5 – 1.0-
Carbon≤ 0.030≤ 0.030
PREN (min.)41 – 42>42

UNS S39274 has slightly higher molybdenum and chromium content, which translates to a higher PREN (Pitting Resistance Equivalent Number), giving it better resistance in seawater and chloride-laden environments.

Mechanical Properties Comparison

PropertyUNS S32760UNS S39274
Tensile Strength ≥ 750 MPa≥ 750 MPa
Yield Strength (0.2%)≥ 550 MPa≥ 550 MPa
Elongation ≥ 25% ≥ 25%
Impact Strength > 100 J @ -50°C> 100 J @ -50°C
Hardness (HBW) ≤ 290 ≤ 290

Mechanically, both grades are nearly identical, but UNS S39274 offers improved corrosion resistance due to its alloying content.

Application Suitability

UNS S32760 is ideal for:
  • Subsea oil & gas components
  • Pulp and paper digesters
  • Heat exchangers
  • Flue gas scrubbers
UNS S39274 is best suited for:
  • Desalination plants
  • High-pressure pumps
  • Marine structural applications
  • Sour gas systems

Both grades meet ASTM A182 and A479 standards, but project-specific corrosion demands may dictate the preferred choice.

Availability and Supply

Both UNS S39274 and UNS S32760 are available through super duplex stainless steel suppliers in multiple product forms:

  • Forged flanges
  • Seamless pipes
  • Fittings and valves
  • Round bars and plates

Choosing the right supplier ensures compliance with international standards and mill test certifications.

FAQs

Is UNS S39274 better than UNS S32760?

While both offer excellent performance, S39274 typically has slightly higher corrosion resistance due to increased chromium and molybdenum content.

Are S32760 and S39274 interchangeable?

They are often used in similar applications, but careful review of service conditions and PREN values is necessary before substitution.

Which is more widely available — S32760 or S39274?

UNS S32760 is more commonly stocked globally, but S39274 is growing in adoption for critical environments like desalination and sour service.

Do both grades comply with ASTM standards?

Yes, both grades are covered under ASTM A182 and A479 standards for forgings and bars, respectively.

admin

Recent Posts

Super Duplex Stainless Steel UNS S39274: Key Insights

Edit with Elementor Loading Super Duplex Stainless Steel UNS S39274 has become a material of…

1 day ago

Top Industrial Use Cases and Applications of UNS S39274

UNS S39274 is a highly alloyed super duplex stainless steel developed for maximum performance in…

1 day ago

Mechanical Properties of UNS S39274 for Critical Industries

UNS S39274 is a highly alloyed super duplex stainless steel grade developed to deliver exceptional…

1 day ago

ASTM A182 UNS S39274 Material Guide for Industry

ASTM A182 UNS S39274 is a widely recognized specification for forged or rolled alloy and…

2 days ago

Ti-6Al-4v ELI: How Titanium Grade 23 Powers Precision

When precision, purity, and performance come together, one titanium alloy stands out—Ti-6Al-4v ELI, commonly known…

1 month ago

How Are 17- 4 PH Stainless Steel Round Bars Used in Manufacturing?

In modern manufacturing, material selection plays a crucial role in determining the quality, durability, and…

1 month ago