ASTM A890 6A
UNS J93380ASTM A890 6A material
Key Engineering Metrics
Instant specifications summary for ASTM A890 6A
General Specifications & Standard Data
ASTM A890Minimum Design Metal Temperature rules for impact testing exemption under ASME B31.3 paragraph 323.2.2.
Mechanical Properties
Room Temp (20°C / 68°F)Allowable Stress Data (ASME B31.3 Table A-1)
asme-bpvcAllowable Stress vs Temperature
ASME B31.3 / BPVC Section II Part D Reference Curve
| Temperature (°C) | Allowable Stress (MPa) | % of Room Temp Rating |
|---|---|---|
| 38 | 197.2 | 100% |
| 100 | 194.4 | 99% |
| 150 | 185.5 | 94% |
| 200 | 183.4 | 93% |
| 250 | 183.4 | 93% |
| 300 | 183.4 | 93% |
| 350 | – | – |
| 400 | – | – |
| 450 | – | – |
| 500 | – | – |
| 550 | – | – |
| 600 | – | – |
| 650 | – | – |
Chemical Composition (% Weight)
Heat & Product Analysis🛡️ Service Compatibility
High PREN (≥34 for 2205, ≥42 for 2507); immune to marine pitting & velocity erosion.
High yield strength & superior resistance to sulfide stress cracking (NACE MR0175).
Outstanding resistance to Chloride Stress Corrosion Cracking (CSCC) up to 150°C.
Risk of 475°C embrittlement and sigma phase precipitation above 280°C.
Ferritic phase undergoes ductile-brittle transition below -50°C.
🔥 Welding & Heat Treatment
No preheat required (keep < 100°C). Control heat input (0.5–2.5 kJ/mm) and interpass temp < 150°C to maintain 50:50 ferrite-austenite phase balance.
PWHT not performed in field. Full solution annealing (1040°C–1120°C + water quench) required if welded without filler or if phase balance is disrupted.
Charpy V-notch impact test required at -40°C or -50°C for weld procedure qualification per ASTM A790 / A815.
Material property data provided is for preliminary engineering reference. Always verify properties against the latest ASME BPVC Section II, ASTM material specification, and Material Test Report (MTR/MTC).