Stainless Steel 329-AW (As-welded deposit)
Heat-treated state
AISI/SAE 329 · UNS S32900
Reference condition for fabricated joints; HAZ ferrite content rises sharply and toughness/corrosion resistance drop — solution anneal after welding whenever possible.
Values for the AW condition
Other 329 tempers and conditions
329 is listed in 4 conditions; see the grade overview at 329.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Forged and solution annealed (ASTM A182 F329-type fittings/flanges) | Forged flanges, fittings and valve bodies; properties depend on section size and quench effectiveness. | 520 | 690 | 22 | 23 HRC | 2.2 % IACS |
AWThis page As-welded deposit | Reference condition for fabricated joints; HAZ ferrite content rises sharply and toughness/corrosion resistance drop — solution anneal after welding whenever possible. | 520 | 700 | 15 | 25 HRC | 2.2 % IACS |
AnnealedDefault solution annealed ~950–1050 °C + rapid quench | Standard supplied condition for plate, sheet, bar, pipe and tube; best combination of corrosion resistance and ductility. | 540 | 720 | 25 | 22 HRC | — |
Cold drawn | Choose for tight-tolerance shafting, fasteners and pump parts where extra strength and a bright surface are wanted. | 700 | 860 | 16 | 29 HRC | — |
What is 329-AW?
329-AW is 329 heat treated to AW — reference condition for fabricated joints; HAZ ferrite content rises sharply and toughness/corrosion resistance drop — solution anneal after welding whenever possible. 329-AW has a yield strength of 520 MPa (75.4 ksi) and a tensile strength of 700 MPa (102 ksi) — stronger than 79% of stainless steel grades. Elongation at break is 15% and the elastic modulus is 200 GPa (29 Msi). 329-AW has a density of 7.8 g/cm³ (0.282 lb/in³), heavier than 50% of stainless steel grades. It melts at 1,400°C (2,552 °F). Annealed is the default condition FabDigit quotes; AW is available on request or by drawing note.
Advantages
- High strength — 520 MPa (75.4 ksi), better than 79% of stainless steel grades
Limitations
- Limited service temperature — 250°C (482 °F), worse than 99% of stainless steel grades
- Low fracture toughness — 45 MPa·√m (41 ksi·√in), worse than 95% of stainless steel grades
- Limited ductility — 15%, worse than 89% of stainless steel grades
- Difficult to machine — 25/100, worse than 88% of stainless steel grades
- Difficult to weld — 35/100, worse than 86% of stainless steel grades
329-AW properties
Typical room-temperature values for 329-AW; 23 are specific to this condition. Other listed values are 329 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
329-AW has a density of 7.8 g/cm³ (0.282 lb/in³), heavier than 50% of stainless steel grades. It melts at 1,400°C (2,552 °F).
Mechanical17
329-AW has a yield strength of 520 MPa (75.4 ksi) and a tensile strength of 700 MPa (102 ksi) — stronger than 79% of stainless steel grades. Elongation at break is 15% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
329-AW is rated for continuous service to 250°C (482 °F). It conducts heat at 15.5 W/m·K (8.96 BTU/hr·ft·°F), better than 53% of stainless steel grades. Thermal expansion is 10.9 µm/m·K (6.06 µin/in·°F).
Electrical3
329-AW conducts electricity at 2.2 % IACS, worse than 61% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (60/100), worse than 58% of stainless steel grades.
Sustainability4
Producing a kilogram of 329-AW takes about 55 MJ of energy and emits 5.5 kg of CO₂ — more than 50% of stainless steel grades. Typical recycled content is 60%.
Manufacturability7
329-AW's machinability is poor (25/100, worse than 88% of stainless steel grades); weldability fair (35/100); formability poor (20/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 329-AW
Is 329 easy to machine?
Machine like duplex: rigid setups, positive-rake coated carbide, 30–60 % of the speed used on 316L, heavy constant feed to cut under the work-hardened layer, generous flood coolant.
Can 329 be welded?
Weldable with GTAW/GMAW/SMAW using over-alloyed duplex or 309Mo/25-9-4 fillers; keep heat input moderate, interpass <150 °C, and solution anneal + quench after welding where the design allows, since the low nitrogen content leaves a brittle, ferrite-rich HAZ.
Can 329 be formed, bent or molded?
Cold forming needs roughly twice the force of 304 with large springback allowance; hot work 1000–1150 °C followed by full solution anneal and water quench — never air-cool from hot working.
What surface finishes work on 329?
Pickle and passivate (HNO₃/HF) after hot work or welding to restore the passive film; takes a good mechanical or electropolished finish, but the two-phase structure can etch with slight relief.
329 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| CASTM A240 S32900 max 0.20 %; modern melts run far lower | ≤ 0.2 | 0.06 |
| Mn | ≤ 1 | 0.6 |
| Si | ≤ 0.75 | 0.5 |
| P | ≤ 0.04 | 0.03 |
| S | ≤ 0.03 | 0 |
| Cr | 23 – 28 | 25.5 |
| Ni | 2.5 – 5 | 4.2 |
| Mo | 1 – 2 | 1.5 |
| Nnot specified in the original AISI 329; EN 1.4460 specifies 0.05–0.20 N | ≤ 0.1 | 0.06 |
| Fe | balance | — |
329-AW — frequently asked
What is 329-AW used for?
329-AW is typically used for heat exchanger tubes, condenser tubing and refinery equipment. In short: original commercial duplex grade; legacy heat-exchanger tube stainless; post-weld anneal usually required.
What is the yield strength of 329-AW?
329-AW has a typical yield strength of 520 MPa (75.4 ksi) and a tensile strength of 700 MPa (102 ksi) — stronger than 79% of stainless steel grades. Strength varies by condition: see the 4 listed tempers.
Is 329-AW easy to machine?
Not especially — machinability is rated poor (25/100, worse than 88% of stainless steel grades). Machine like duplex: rigid setups, positive-rake coated carbide, 30–60 % of the speed used on 316L, heavy constant feed to cut under the work-hardened layer, generous flood coolant.
Can 329-AW be welded?
With care — weldability is rated fair (35/100). Weldable with GTAW/GMAW/SMAW using over-alloyed duplex or 309Mo/25-9-4 fillers; keep heat input moderate, interpass <150 °C, and solution anneal + quench after welding where the design allows, since the low nitrogen content leaves a brittle, ferrite-rich HAZ.
What surface finishes work on 329-AW?
Pickle and passivate (HNO₃/HF) after hot work or welding to restore the passive film; takes a good mechanical or electropolished finish, but the two-phase structure can etch with slight relief.
Can 329-AW be formed, bent or molded?
Cold forming needs roughly twice the force of 304 with large springback allowance; hot work 1000–1150 °C followed by full solution anneal and water quench — never air-cool from hot working.
What is the maximum service temperature of 329-AW?
329-AW is rated for continuous use to about 250°C (482 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 329 Annealed and 329-CD?
Annealed is the default condition — standard supplied condition for plate, sheet, bar, pipe and tube; best combination of corrosion resistance and ductility. CD: choose for tight-tolerance shafting, fasteners and pump parts where extra strength and a bright surface are wanted. Yield strength is 540 MPa in Annealed versus 700 MPa in CD.
Sources
- ASTM A240/A240M — Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip — ASTM International (2023)
- ASTM A789/A790 — Ferritic/Austenitic Stainless Steel Tubing and Pipe — ASTM International (2021)
- EN 10088-1/-2 — Stainless steels, grade 1.4460 (X3CrNiMoN27-5-2) — CEN (2014)
- ASM Specialty Handbook: Stainless Steels — ASM International (1994)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.