Stainless Steel 310HCb
UNS S31041
AISI 310HCb (UNS S31041) combines the higher carbon of 310H with niobium stabilization, giving elevated-temperature creep strength plus resistance to sensitization within the 25Cr-20Ni austenitic system.
Reference datasheet — 310HCb is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the Annealed condition
310HCb tempers and conditions
310HCb is supplied in 4 conditions, soft to hard. Annealed is the default FabDigit quotes; the values on this page are for it.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
AnnealedDefault solution annealed (~1050–1150 °C) and rapidly cooled | Standard supply condition for plate, pipe and tube; maximum ductility and the condition for which ASME creep/allowable stresses apply. | 260 | 590 | 45 | 170 HB | — |
As-welded deposit | Condition of fabricated furnace assemblies welded with matching Nb-bearing 310 filler; Nb keeps HAZ sensitization-resistant so PWHT is usually unnecessary. | 300 | 570 | 32 | 185 HB | 2.1 % IACS |
Cold drawn | Choose for tighter dimensional tolerance and higher room-temperature strength in bar/tube; strength gain is lost above ~600 °C service. | 450 | 690 | 30 | 17 HRC | 2.2 % IACS |
1/4 Hard | Occasional strip/wire condition where extra room-temperature strength and springback are needed; not used for creep-governed hot service. | 515 | 760 | 20 | 22 HRC | 2.2 % IACS |
Supply forms, finishes and certifications
Ways 310HCb is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
CRA | Cold Rolled, Annealed | Surface finish |
HRAP | Hot Rolled, Annealed and Pickled | Surface finish |
What is 310HCb?
AISI 310HCb (UNS S31041) combines the higher carbon of 310H with niobium stabilization, giving elevated-temperature creep strength plus resistance to sensitization within the 25Cr-20Ni austenitic system. It is specified for welded high-temperature pressure vessels and petrochemical furnace piping to 1100 °C and is available annealed, HRAP, cold-rolled annealed, cold-drawn, 1/4-hard and as-welded. Annealed values are near 260 MPa yield, 590 MPa tensile, 45 % elongation and 170 HB. Machining is slow, availability is limited and cost is high; 310H or 310S covers less demanding duty. 310HCb 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). 310HCb has a yield strength of 260 MPa (37.7 ksi) and a tensile strength of 590 MPa (85.6 ksi) — weaker than 84% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 200 GPa (29 Msi).
What is 310HCb used for?
- High-temperature pressure vessels
- Petrochemical furnace piping
- Welded reformer internals
- Superheater and reheater tubing
- Furnace hangers and supports
- Hot-gas ducting and expansion joints
Advantages
- High service temperature — 1,100°C (2,012 °F), better than 96% of stainless steel grades
- Tough — resists crack growth — 200 MPa·√m (182 ksi·√in), better than 86% of stainless steel grades
- Ductile — tolerates forming and impact — 45%, better than 76% of stainless steel grades
Limitations
- High embodied carbon — 5.8 kg CO₂/kg, worse than 86% of stainless steel grades
- Low strength — 260 MPa (37.7 ksi), worse than 84% of stainless steel grades
310HCb properties
Typical room-temperature values for 310HCb-Annealed; bars are the position among stainless steel grades.
Physical3
310HCb 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).
Mechanical16
310HCb has a yield strength of 260 MPa (37.7 ksi) and a tensile strength of 590 MPa (85.6 ksi) — weaker than 84% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
310HCb is rated for continuous service to 1,100°C (2,012 °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
310HCb conducts electricity at 2.2 % IACS, worse than 61% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is very good (72/100), better than 73% of stainless steel grades.
Sustainability4
Producing a kilogram of 310HCb takes about 68 MJ of energy and emits 5.8 kg of CO₂ — more than 80% of stainless steel grades. Typical recycled content is 60%.
Manufacturability7
310HCb's machinability is poor (32/100, worse than 62% of stainless steel grades); weldability very good (70/100); formability good (65/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the stainless steel family
Yield strength against density for every stainless steel grade FabDigit runs. 310HCb is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 310HCb
Is 310HCb easy to machine?
Slow speeds, heavy positive-rake carbide, rigid setups and flood coolant — the alloy work-hardens fast and produces stringy chips; avoid dwelling to prevent glazing.
Can 310HCb be welded?
GTAW/SMAW/FCAW with matching 310 or Nb-bearing 310 filler, low heat input, interpass ≤150 °C; keep ferrite-free weld pools clean to avoid hot cracking and no PWHT normally needed thanks to Nb stabilization.
Can 310HCb be formed, bent or molded?
Cold forms readily but with high force and springback (work-hardening rate ~2× carbon steel); hot work at 1150–1200 °C and finish above 950 °C, then solution anneal 1050–1150 °C and cool fast.
310HCb 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 |
|---|---|---|
| Ccontrolled high carbon for creep strength | 0.04 – 0.1 | 0.07 |
| Cr | 24 – 26 | 25 |
| Ni | 19 – 22 | 20.5 |
| Nbstabilizer; forms NbC and prevents sensitization | 0.2 – 1 | 0.5 |
| Mn | ≤ 2 | 1.5 |
| Siaids oxidation resistance | ≤ 1.5 | 0.8 |
| N | ≤ 0.03 | 0.02 |
| P | ≤ 0.05 | 0.03 |
| S | ≤ 0.03 | 0.01 |
| Fe | balance | — |
What surface finishes work on 310HCb?
Pickle/passivate or bead-blast after hot work to restore the Cr₂O₃ film; can be electropolished or mechanically polished, no anodizing — protect from chloride-bearing residues before high-temperature service.
Surface treatments FabDigit runs on stainless steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Passivation
Organic Coating
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Stainless Steel 310HCb in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- S31041
How much does 310HCb cost?
310HCb is a high-cost stainless steel ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
310HCb — frequently asked
What is 310HCb used for?
310HCb is typically used for high-temperature pressure vessels, petrochemical furnace piping, welded reformer internals, superheater and reheater tubing, furnace hangers and supports and hot-gas ducting and expansion joints. In short: stabilized high-carbon 310; creep strength with stabilization; welded high-temperature pressure parts.
What is the yield strength of 310HCb?
310HCb has a typical yield strength of 260 MPa (37.7 ksi) and a tensile strength of 590 MPa (85.6 ksi) — weaker than 84% of stainless steel grades. Strength varies by condition: see the 4 listed tempers.
Is 310HCb easy to machine?
Not especially — machinability is rated poor (32/100, worse than 62% of stainless steel grades). Slow speeds, heavy positive-rake carbide, rigid setups and flood coolant — the alloy work-hardens fast and produces stringy chips; avoid dwelling to prevent glazing.
Can 310HCb be welded?
Yes — weldability is rated very good (70/100). GTAW/SMAW/FCAW with matching 310 or Nb-bearing 310 filler, low heat input, interpass ≤150 °C; keep ferrite-free weld pools clean to avoid hot cracking and no PWHT normally needed thanks to Nb stabilization.
What surface finishes work on 310HCb?
Pickle/passivate or bead-blast after hot work to restore the Cr₂O₃ film; can be electropolished or mechanically polished, no anodizing — protect from chloride-bearing residues before high-temperature service.
Can 310HCb be formed, bent or molded?
Cold forms readily but with high force and springback (work-hardening rate ~2× carbon steel); hot work at 1150–1200 °C and finish above 950 °C, then solution anneal 1050–1150 °C and cool fast.
What is the maximum service temperature of 310HCb?
310HCb is rated for continuous use to about 1,100°C (2,012 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 310HCb Annealed and 310HCb-CD?
Annealed is the default condition — standard supply condition for plate, pipe and tube; maximum ductility and the condition for which ASME creep/allowable stresses apply. CD: choose for tighter dimensional tolerance and higher room-temperature strength in bar/tube; strength gain is lost above ~600 °C service. Yield strength is 260 MPa in Annealed versus 450 MPa in CD.
How much does 310HCb cost?
310HCb is a high-cost stainless steel ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- ASTM A240/A240M — Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip (UNS S31041) — ASTM International (2023)
- ASTM A213/A213M — Seamless Ferritic and Austenitic Alloy-Steel Boiler, Superheater and Heat-Exchanger Tubes — ASTM International (2022)
- ASTM A312/A312M — Seamless, Welded and Heavily Cold Worked Austenitic Stainless Steel Pipes — ASTM International (2022)
- ASME BPVC Section II Part D — Allowable stresses for S31041 — ASME (2023)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- 310S/310H/310HCb heat-resisting austenitic stainless datasheets — Outokumpu / Sandmeyer Steel / Sandvik (2022)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.