Related Specifications
Surface Treatments
Certifications
- ISO 9001 - 2015 Certified
- PED 2014/68/EC
- NACE MR0175/ISO 15156-2
- NORSOK M-650
- DFAR
- MERKBLATT AD 2000 W2/W7/W10
ASTM A1082/A1082M Grade S32506 | Super Duplex Stainless Steel
Exceptional corrosion resistance and mechanical strength for severe industrial service
Grade S32506 (UNS S32506) is a high-performance super duplex stainless steel containing 25% chromium, 6% nickel, and 3% molybdenum with nitrogen strengtheners to deliver exceptional resistance to localized corrosion and structural integrity in extreme environments. Featuring a balanced ferritic-austenitic microstructure, this grade provides superior resistance to chloride-induced pitting, crevice corrosion, and stress corrosion cracking (SCC) compared to standard duplex and austenitic alloys. S32506 is widely utilized in aggressive chemical processing, offshore oil and gas production, marine engineering, and desalination plants where mechanical durability and long-term corrosion resistance are essential. Its unique combination of high yield strength and excellent fatigue properties allows for optimized equipment designs and extended service life in severe industrial applications.
ASTM A1082/A1082M Grade S32506 Chemical RequirementsA
| Grades | UNS Designation | Type | C | Mn | P | S | Si | Cr | Ni | Mo | N | Other ElementsB |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ASTM A1082/A1082M Duplex (Ferritic-Austenitic) Grades | S32506 | . . . | 0.030 | 1.00 | 0.040 | 0.015 | 0.90 | 24.0-26.0 | 5.5-7.2 | 3.0-3.5 | 0.08-2.0 | W 0.05-0.30 |
|
||||||||||||
ASTM A1082/A1082M Grade S32506 Mechanical Properties
| UNS Designation | Solution Temperature, °F [°C] (B, C) | Tensile Strength, min, ksi [MPa] | Yield Strength, 0.2% offset, min, ksi [MPa] | Elongation in 2" [50 mm] or 4D, min, % | Rockwell HRC, max | Brinell max (D) |
|---|---|---|---|---|---|---|
| S32506 | 1870 - 2050 [1020 - 1120] | 90 [620] | 65 [450] | 18 | 32 | 302 |
|
||||||
ASTM A1082/A1082M Markings
| UNS Designation | Grade Symbol |
|---|---|
| S32506 | TB 32506 |
Frequently Asked Questions
What is Super-Duplex 2506 (S32506)?
Super-Duplex 2506 (S32506) is a stainless steel grade covered under ASTM A1082/A1082M for high-strength bolting in special-purpose applications such as pressure vessels. UNS designation S32506. Available as bolts, studs, screws and nuts manufactured by TorqBolt for global oil/gas/nuclear/power/marine sectors.
What are the mechanical properties of Super-Duplex 2506 (S32506) per ASTM A1082?
Mechanical property requirements for S32506 are defined in ASTM A1082 Table 2 (PH grade solution treatment) or Table 4 (duplex annealed condition). Properties vary by treatment condition - refer to the bolting specification for the H-condition (PH) or annealed yield/tensile/elongation/hardness requirements applicable to your order.
Is Super-Duplex 2506 (S32506) suitable for sour service (NACE MR0175)?
Refer to NACE MR0175 / ISO 15156 Tables A.16-A.19. Most A1082 duplex grades are permitted at ≤28 HRC; PH grades require condition-specific qualification (typically H1150 for 17-4 PH at 28 HRC). TorqBolt supplies sour-service certified product on request with full PMI + hardness traceability.
What ASME / ISO dimensional standards can Super-Duplex 2506 (S32506) be supplied to?
This grade is available across the full ASME and ISO bolting dimensional standards covered on this site - ASME B18.2.1 (hex bolts, hex cap screws, lag screws), B18.2.2 (hex nuts, square nuts, lock nuts), B18.3 (socket head cap screws), B18.31.2 (clamping studs), B16.5 (flange stud bolts), ISO 4032 / 4033 / 4035 (metric nuts), and metric B18.2.3.xM / B18.2.4.xM series.
References & Standards
- ASTM A1082 / A1082M - Standard Specification for High-Strength Precipitation-Hardening and Duplex Stainless Steel Bolting for Special-Purpose Applications (current edition 2016, active)
- ASTM A962 / A962M - General Requirements for Special-Purpose Bolting Materials
- ASTM A370 - Mechanical Testing of Steel Products
- NACE MR0175 / ISO 15156 - Sour-service hardness limits for petroleum & natural gas industries
- ASME B18 series - Dimensional standards for bolts, screws, nuts, studs
- ISO 4032 / 4033 / 4035 - Metric hexagon nut dimensional standards
Satisfaction Survey
