Stainless Steel 310Cb-AW (As-welded deposit)
Heat-treated state
UNS S31040
Reference condition for welded pipe and fabrications used without post-weld solution anneal — the reason 310Cb exists.
Values for the AW condition
Other 310Cb tempers and conditions
310Cb is listed in 4 conditions; see the grade overview at 310Cb.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Stabilize annealed | Use when maximum immunity to intergranular attack/polythionic-acid cracking after service or welding is required, by tying carbon up as NbC. | 305 | 610 | 42 | 165 HB | 2.2 % IACS |
AnnealedDefault Annealed (solution annealed, 1050–1120 °C, rapid cool) | Standard stocked condition for plate, sheet, bar and pipe; maximum ductility and corrosion/oxidation resistance. | 310 | 620 | 45 | 160 HB | — |
AWThis page As-welded deposit | Reference condition for welded pipe and fabrications used without post-weld solution anneal — the reason 310Cb exists. | 330 | 600 | 35 | 180 HB | 2.2 % IACS |
Cold drawn | Pick for machined fasteners, pins and shafts needing higher yield and better surface/tolerance than hot-finished bar. | 550 | 760 | 25 | 21 HRC | — |
What is 310Cb-AW?
310Cb-AW is 310Cb heat treated to AW — reference condition for welded pipe and fabrications used without post-weld solution anneal — the reason 310Cb exists. 310Cb-AW has a yield strength of 330 MPa (47.9 ksi) and a tensile strength of 600 MPa (87 ksi) — weaker than 57% of stainless steel grades. Elongation at break is 35% and the elastic modulus is 196 GPa (28.4 Msi). 310Cb-AW has a density of 7.98 g/cm³ (0.288 lb/in³), heavier than 85% 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 service temperature — 1,050°C (1,922 °F), better than 91% of stainless steel grades
Limitations
- Difficult to machine — 25/100, worse than 88% of stainless steel grades
- High embodied carbon — 6 kg CO₂/kg, worse than 88% of stainless steel grades
310Cb-AW properties
Typical room-temperature values for 310Cb-AW; 22 are specific to this condition. Other listed values are 310Cb reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
310Cb-AW has a density of 7.98 g/cm³ (0.288 lb/in³), heavier than 85% of stainless steel grades. It melts at 1,400°C (2,552 °F).
Mechanical15
310Cb-AW has a yield strength of 330 MPa (47.9 ksi) and a tensile strength of 600 MPa (87 ksi) — weaker than 57% of stainless steel grades. Elongation at break is 35% and the elastic modulus is 196 GPa (28.4 Msi).
Thermal6
310Cb-AW is rated for continuous service to 1,050°C (1,922 °F). It conducts heat at 14.2 W/m·K (8.2 BTU/hr·ft·°F), worse than 76% of stainless steel grades. Thermal expansion is 15.9 µm/m·K (8.83 µin/in·°F).
Electrical3
310Cb-AW conducts electricity at 2.2 % IACS, worse than 61% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (65/100), better than 56% of stainless steel grades.
Sustainability4
Producing a kilogram of 310Cb-AW takes about 80 MJ of energy and emits 6 kg of CO₂ — more than 89% of stainless steel grades. Typical recycled content is 70%.
Manufacturability7
310Cb-AW's machinability is poor (25/100, worse than 88% of stainless steel grades); weldability very good (70/100); formability fair (45/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 310Cb-AW
Is 310Cb easy to machine?
Gummy and strongly work-hardening: use rigid setups, positive-rake carbide, 25–60 m/min, heavy constant feed, no dwell, flood coolant; Nb carbides accelerate edge wear.
Can 310Cb be welded?
Weld with GTAW/GMAW/SMAW using matching 310Cb/ER310 or Nb-stabilized filler, low heat input, no preheat, interpass below ~150 °C; stabilization means no post-weld solution anneal is normally needed, but watch hot cracking from fully austenitic structure.
Can 310Cb be formed, bent or molded?
Cold forms well but needs ~50 % more press force than 304 and generous bend radii due to high work-hardening and springback; hot work 1150–1200 °C, finish above 950 °C, then solution anneal.
What surface finishes work on 310Cb?
Pickle and passivate or electropolish after fabrication to restore the chromium oxide film; no anodizing — descale heat tint with acid paste or abrasive blast plus passivation.
310Cb 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 |
|---|---|---|
| CNb stabilization ties up carbon as NbC | ≤ 0.08 | 0.05 |
| Mn | ≤ 2 | 1.5 |
| Sisome specs limit to 0.75 max | ≤ 1.5 | 0.8 |
| P | ≤ 0.05 | — |
| S | ≤ 0.03 | — |
| Cr | 24 – 26 | 25 |
| Ni | 19 – 22 | 20.5 |
| NbNb (+Ta) stabilizer; historically written as Cb | 0.75 – 1.5 | 1 |
| Fe | balance | — |
310Cb-AW — frequently asked
What is 310Cb-AW used for?
310Cb-AW is typically used for furnace components and hangers, welded high-temperature ducting, radiant tubes, heat-treating fixtures, recuperator sections and flue and stack liners. In short: stabilized 310 for welding; resists post-service sensitization; 1100 °C furnace grade.
What is the yield strength of 310Cb-AW?
310Cb-AW has a typical yield strength of 330 MPa (47.9 ksi) and a tensile strength of 600 MPa (87 ksi) — weaker than 57% of stainless steel grades. Strength varies by condition: see the 4 listed tempers.
Is 310Cb-AW easy to machine?
Not especially — machinability is rated poor (25/100, worse than 88% of stainless steel grades). Gummy and strongly work-hardening: use rigid setups, positive-rake carbide, 25–60 m/min, heavy constant feed, no dwell, flood coolant; Nb carbides accelerate edge wear.
Can 310Cb-AW be welded?
Yes — weldability is rated very good (70/100). Weld with GTAW/GMAW/SMAW using matching 310Cb/ER310 or Nb-stabilized filler, low heat input, no preheat, interpass below ~150 °C; stabilization means no post-weld solution anneal is normally needed, but watch hot cracking from fully austenitic structure.
What surface finishes work on 310Cb-AW?
Pickle and passivate or electropolish after fabrication to restore the chromium oxide film; no anodizing — descale heat tint with acid paste or abrasive blast plus passivation.
Can 310Cb-AW be formed, bent or molded?
Cold forms well but needs ~50 % more press force than 304 and generous bend radii due to high work-hardening and springback; hot work 1150–1200 °C, finish above 950 °C, then solution anneal.
What is the maximum service temperature of 310Cb-AW?
310Cb-AW is rated for continuous use to about 1,050°C (1,922 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 310Cb Annealed and 310Cb-CD?
Annealed is the default condition — standard stocked condition for plate, sheet, bar and pipe; maximum ductility and corrosion/oxidation resistance. CD: pick for machined fasteners, pins and shafts needing higher yield and better surface/tolerance than hot-finished bar. Yield strength is 310 MPa in Annealed versus 550 MPa in CD.
Sources
- ASTM A240/A240M — Chromium and Chromium-Nickel Stainless Steel Plate, Sheet and Strip (UNS S31040) — ASTM International (2023)
- ASTM A479/A312 — stainless bar and welded/seamless pipe requirements — ASTM International (2022)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Specialty Handbook — Stainless Steels — ASM International (1994)
- 310/310S/310Cb heat-resisting stainless datasheets — Outokumpu / Sandvik / NAS (2022)
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.