Stainless Steel 410Cb
UNS S41040 · AISI/SAE XM-30
410Cb is a niobium (columbium)-stabilized 12 % Cr martensitic stainless (UNS S41040, XM-30) in which the Nb addition ties up carbon so the weld heat-affected zone resists chromium-carbide sensitization and embrittlement.
Reference datasheet — 410Cb 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
410Cb tempers and conditions
410Cb is supplied in 6 conditions, soft to hard. Annealed is the default FabDigit quotes; the values on this page are for it.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
AnnealedDefault subcritical/full anneal, soft ferritic + carbide condition | Standard stock condition for bar, plate and forgings: softest, most machinable and formable, ready for subsequent hardening. | 290 | 490 | 25 | 170 HB | — |
Normalized and tempered | Used for heavy forgings and weldments where full oil quenching risks distortion or cracking but medium strength is required. | 450 | 655 | 20 | 18 HRC | — |
Cold drawn | Choose for straight, close-tolerance bright bar and wire where modest strength gain and better surface finish are wanted without hardening. | 500 | 640 | 15 | 200 HB | — |
double tempered for sour-service hardness cap | Specify when NACE MR0175/ISO 15156-type sour service or H2S/SSC resistance caps hardness at 22 HRC. | 585 | 740 | 20 | 21 HRC | — |
Quenched and tempered | General-purpose hardened condition for valve trim, shafts, pump parts and fasteners needing strength plus reasonable toughness and corrosion behaviour. | 620 | 790 | 18 | 23 HRC | — |
Q&T high strength | Choose for wear parts, cutlery-type blades and hard seats where maximum hardness matters more than impact toughness; avoid 400–550 °C tempering (temper embrittlement). | 1,050 | 1,350 | 12 | 43 HRC | — |
What is 410Cb?
410Cb is a niobium (columbium)-stabilized 12 % Cr martensitic stainless (UNS S41040, XM-30) in which the Nb addition ties up carbon so the weld heat-affected zone resists chromium-carbide sensitization and embrittlement. It is chosen over plain 410 for welded pump, valve and petrochemical hardware, and is supplied as bar, plate and forgings; annealed properties are about 290 MPa yield, 490 MPa tensile, 25 % elongation and 170 HB, with service to 650 °C. Martensite still forms on cooling, so preheat and post-weld tempering remain necessary, and corrosion resistance stays modest — below austenitic 304. Consider 415 (CA6NM) where higher as-welded toughness is required. 410Cb has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 65% of stainless steel grades. It melts at 1,480°C (2,696 °F). 410Cb has a yield strength of 290 MPa (42.1 ksi) and a tensile strength of 490 MPa (71.1 ksi) — weaker than 72% of stainless steel grades. Elongation at break is 25% and the elastic modulus is 200 GPa (29 Msi).
What is 410Cb used for?
- welded pump and valve components
- petrochemical equipment
- flanges
Advantages
- High electrical conductivity — 3 % IACS, better than 95% of stainless steel grades
- Low embodied carbon — 3.2 kg CO₂/kg, better than 95% of stainless steel grades
- Easy to machine — 50/100, better than 90% of stainless steel grades
- Conducts heat well — 24.9 W/m·K (14.4 BTU/hr·ft·°F), better than 87% of stainless steel grades
Limitations
- Needs corrosion protection — 33/100, worse than 98% of stainless steel grades
- Low fracture toughness — 90 MPa·√m (81.9 ksi·√in), worse than 75% of stainless steel grades
410Cb properties
Typical room-temperature values for 410Cb-Annealed; bars are the position among stainless steel grades.
Physical3
410Cb has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 65% of stainless steel grades. It melts at 1,480°C (2,696 °F).
Mechanical16
410Cb has a yield strength of 290 MPa (42.1 ksi) and a tensile strength of 490 MPa (71.1 ksi) — weaker than 72% of stainless steel grades. Elongation at break is 25% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
410Cb is rated for continuous service to 650°C (1,202 °F). It conducts heat at 24.9 W/m·K (14.4 BTU/hr·ft·°F), better than 87% of stainless steel grades. Thermal expansion is 9.9 µm/m·K (5.5 µin/in·°F).
Electrical3
410Cb conducts electricity at 3 % IACS, better than 95% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is poor (33/100), worse than 98% of stainless steel grades.
Sustainability4
Producing a kilogram of 410Cb takes about 45 MJ of energy and emits 3.2 kg of CO₂ — less than 91% of stainless steel grades. Typical recycled content is 60%.
Manufacturability7
410Cb's machinability is fair (50/100, better than 90% of stainless steel grades); weldability good (60/100); formability fair (50/100).
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. 410Cb is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 410Cb
Is 410Cb easy to machine?
Machine in the annealed or ≤26 HRC tempered condition with sharp, rigid tooling, positive rake carbide and generous coolant; gummy chips and work hardening are the main issues — 410Cb cuts at roughly half the rate of 1212 free-cutting steel.
Can 410Cb be welded?
The main reason to choose this grade: Nb stabilization prevents HAZ chromium-carbide sensitization, but martensite still forms — preheat 200–300 °C, use 410/410NiMo or austenitic 309 filler, and post-weld temper ~700–760 °C for toughness.
Can 410Cb be formed, bent or molded?
Cold form only in the annealed condition with generous bend radii (≥2t); hot work 1150–1200 °C and cool slowly to avoid quench cracks, then always anneal or temper after hot working.
410Cb 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 |
|---|---|---|
| C0.15 max per UNS S41040 | ≤ 0.15 | 0.1 |
| Mn | ≤ 1 | 0.6 |
| Si | ≤ 1 | 0.5 |
| P | ≤ 0.04 | 0.03 |
| S | ≤ 0.03 | 0.01 |
| Cr | 11.5 – 13.5 | 12.5 |
| Niresidual limit typical of mill practice | ≤ 0.75 | 0.35 |
| Nbcolumbium (Cb) stabilizer — ties up carbon as NbC | 0.05 – 0.3 | 0.15 |
| Fe | balance |
What surface finishes work on 410Cb?
Passivate per ASTM A967 (nitric or citric) after machining; can be electropolished, hard-chrome plated or nitrided; polishes to a good mirror finish in the hardened condition — never leave free iron or scale on the surface.
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 410Cb in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- S41040
- AISI / SAE
- XM-30
How much does 410Cb cost?
410Cb is a premium-cost stainless steel ($$$), cheaper than about 51% 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.
410Cb — frequently asked
What is 410Cb used for?
410Cb is typically used for welded pump and valve components, petrochemical equipment and flanges. In short: weldable 410 variant; sensitization-resistant HAZ; service to 650 °C.
What is the yield strength of 410Cb?
410Cb has a typical yield strength of 290 MPa (42.1 ksi) and a tensile strength of 490 MPa (71.1 ksi) — weaker than 72% of stainless steel grades. Strength varies by condition: see the 6 listed tempers.
Is 410Cb easy to machine?
Reasonably — machinability is rated fair (50/100, better than 90% of stainless steel grades). Machine in the annealed or ≤26 HRC tempered condition with sharp, rigid tooling, positive rake carbide and generous coolant; gummy chips and work hardening are the main issues — 410Cb cuts at roughly half the rate of 1212 free-cutting steel.
Can 410Cb be welded?
Yes — weldability is rated good (60/100). The main reason to choose this grade: Nb stabilization prevents HAZ chromium-carbide sensitization, but martensite still forms — preheat 200–300 °C, use 410/410NiMo or austenitic 309 filler, and post-weld temper ~700–760 °C for toughness.
What surface finishes work on 410Cb?
Passivate per ASTM A967 (nitric or citric) after machining; can be electropolished, hard-chrome plated or nitrided; polishes to a good mirror finish in the hardened condition — never leave free iron or scale on the surface.
Can 410Cb be formed, bent or molded?
Cold form only in the annealed condition with generous bend radii (≥2t); hot work 1150–1200 °C and cool slowly to avoid quench cracks, then always anneal or temper after hot working.
What is the maximum service temperature of 410Cb?
410Cb is rated for continuous use to about 650°C (1,202 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 410Cb Annealed and 410Cb-CD?
Annealed is the default condition — standard stock condition for bar, plate and forgings: softest, most machinable and formable, ready for subsequent hardening. CD: choose for straight, close-tolerance bright bar and wire where modest strength gain and better surface finish are wanted without hardening. Yield strength is 290 MPa in Annealed versus 500 MPa in CD.
How much does 410Cb cost?
410Cb is a premium-cost stainless steel ($$$), cheaper than about 51% 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 A276/A276M Stainless Steel Bars and Shapes — ASTM International (2023)
- ASTM A479/A479M Stainless Steel Bars and Shapes for Pressure Vessels — ASTM International (2020)
- SAE/ASTM Unified Numbering System (UNS S41040, XM-30) — SAE International / ASTM (2017)
- ASM Specialty Handbook: Stainless Steels — ASM International (1994)
- ASM Handbook Vol.1: Properties and Selection — Irons, Steels, and High-Performance Alloys — ASM International (1990)
- Machinery's Handbook (machinability ratings for stainless grades) — Industrial Press (2020)
- NACE MR0175/ISO 15156-3 (hardness limits for martensitic stainless in sour service) — NACE/ISO (2020)
- SMM / Mysteel — SMM / Mysteel (2025)
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.