What is ASTM A790 equivalent to?
A 790/A 790M – 09.pdf
What Is ASTM A790?
ASTM A790 is the standard specification for seamless and welded pipe made from duplex stainless steels, which combine austenitic and ferritic structures to provide:
Higher strength than austenitic stainless steel
Superior resistance to stress corrosion cracking and pitting
Excellent performance in chloride-containing environments
This standard covers pipe used in industries like:
Offshore oil and gas
Chemical processing
Desalination systems
Marine applications
Common Grades Covered by ASTM A790
| Grade (UNS) | Common Name | Description |
|---|---|---|
| S31803 | 2205 Duplex | The original duplex grade with balanced corrosion and strength |
| S32205 | Enhanced 2205 | Improved version of S31803 with stricter composition for better corrosion resistance |
| S32750 | Super Duplex 2507 | Higher alloy content for extreme corrosion resistance |
| S32760 | Zeron 100 | Super duplex with excellent mechanical strength and seawater resistance |
ASTM A790 Equivalent Materials and Standards
| ASTM | UNS Number | EN / DIN Equivalent | ISO / Other |
|---|---|---|---|
| A790 S31803 | UNS S31803 | EN 1.4462 / X2CrNiMoN22-5-3 | ISO 31803, NFA 49-217 |
| A790 S32205 | UNS S32205 | EN 1.4462 (same) | NORSOK MDS D45 |
| A790 S32750 | UNS S32750 | EN 1.4410 / X2CrNiMoN25-7-4 | NORSOK MDS D50 |
| A790 S32760 | UNS S32760 | EN 1.4501 / X2CrNiMoCuWN25-7-4 | Zeron® 100 (Trademark) |
👉 Note: S32205 is now the preferred grade over S31803 due to tighter composition and more consistent corrosion resistance.
What is the chemical composition of ASTM A790?
What are the mechanical properties of ASTM A790?
ASTM A790 vs ASTM A312: What's the Difference?
| Property | ASTM A790 | ASTM A312 |
|---|---|---|
| Material Type | Duplex stainless steel | Austenitic stainless steel (304, 316 etc.) |
| Strength | Higher (450–620 MPa yield) | Moderate (≥205 MPa yield) |
| Corrosion | Superior chloride resistance | General corrosion resistance |
| Typical Grades | S31803, S32205, S32750 | 304/304L, 316/316L |
| Applications | Oil & gas, marine, power | Food, pharma, chemical |
Delivery Conditions and Testing (Per ASTM A790)
Heat treatment: Solution annealed
NDT: ECT or hydrostatic testing required
Certification: Mill Test Certificate (EN 10204 3.1 or 3.2)
Marking: Grade, size, schedule, heat number, spec (e.g., A790 S32205 SCH40)
