Stainless Steel 440B · heat-treated state
Stainless Steel 440B Hardened + Cryo + Double Temper
Properties of the Hardened + Cryo + Double Temper condition, compared with the other 440B tempers.
Choose for gauge-stable, maximum-hardness parts (bearing balls, precision cutlery) where retained austenite must be transformed.
What is 440B Hardened + Cryo + Double Temper?
440B Hardened + Cryo + Double Temper is 440B heat treated to Hardened + Cryo + Double Temper — choose for gauge-stable, maximum-hardness parts (bearing balls, precision cutlery) where retained austenite must be transformed. 440B Hardened + Cryo + Double Temper has a yield strength of 1,700 MPa (247 ksi) and a tensile strength of 1,930 MPa (280 ksi) — stronger than 100% of stainless steel grades. Elongation at break is 2% and the elastic modulus is 200 GPa (29 Msi). 440B Hardened + Cryo + Double Temper has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 66% of stainless steel grades. It melts at 1,370°C (2,498 °F). Annealed is the default condition FabDigit quotes; Hardened + Cryo + Double Temper is available on request or by drawing note.
Advantages
- High strength — 1,700 MPa (247 ksi), better than 100% of stainless steel grades
- Polishes to a fine finish — 92/100, better than 100% of stainless steel grades
- High electrical conductivity — 2.9 % IACS, better than 87% of stainless steel grades
- Conducts heat well — 24.2 W/m·K (14 BTU/hr·ft·°F), better than 84% of stainless steel grades
Limitations
- Limited ductility — 2%, worse than 100% of stainless steel grades
- Difficult to machine — 6/100, worse than 100% of stainless steel grades
- Low fracture toughness — 40 MPa·√m (36.4 ksi·√in), worse than 98% of stainless steel grades
- Difficult to weld — 20/100, worse than 96% of stainless steel grades
- Needs corrosion protection — 50/100, worse than 79% of stainless steel grades
440B Hardened + Cryo + Double Temper properties
Typical room-temperature values for 440B Hardened + Cryo + Double Temper — 9 properties are specific to this condition; the rest are grade-level values shared by every 440B temper. Each bar shows where the value sits among the stainless steel grades in FabDigit's library — further right is higher.
Physical3
440B Hardened + Cryo + Double Temper has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 66% of stainless steel grades. It melts at 1,370°C (2,498 °F).
Mechanical16
440B Hardened + Cryo + Double Temper has a yield strength of 1,700 MPa (247 ksi) and a tensile strength of 1,930 MPa (280 ksi) — stronger than 100% of stainless steel grades. Elongation at break is 2% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
440B Hardened + Cryo + Double Temper is rated for continuous service to 425°C (797 °F). It conducts heat at 24.2 W/m·K (14 BTU/hr·ft·°F), better than 84% of stainless steel grades. Thermal expansion is 10.2 µm/m·K (5.67 µin/in·°F).
Electrical3
440B Hardened + Cryo + Double Temper conducts electricity at 2.9 % IACS, better than 87% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is fair (50/100), worse than 79% of stainless steel grades.
Sustainability4
Producing a kilogram of 440B Hardened + Cryo + Double Temper takes about 53 MJ of energy and emits 4.2 kg of CO₂ — less than 67% of stainless steel grades. Typical recycled content is 50%.
Manufacturability7
440B Hardened + Cryo + Double Temper's machinability is not recommended (6/100, worse than 100% of stainless steel grades); weldability poor (20/100); formability poor (30/100).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other 440B tempers and conditions
440B is also supplied in 4 other conditions. The full side-by-side table is on the 440B overview.
- AnnealedDefaultStandard stock condition for bar, strip and blanks that will be machined and then hardened by the user.425 MPa yield · 220 HB
- Hardened + Cryo + Double TemperChoose for gauge-stable, maximum-hardness parts (bearing balls, precision cutlery) where retained austenite must be transformed.1,700 MPa yield · 58 HRC
- Hardened & TemperedThe standard service condition for blades, valve seats and wear parts: maximum hardness, wear resistance and best corrosion resistance of the hardened states.1,620 MPa yield · 56 HRC
- H&T 50-52 HRCSlightly tougher/lower-hardness option for shafts and highly stressed parts; corrosion resistance drops because of carbide precipitation, so avoid in wet chloride service.1,500 MPa yield · 51 HRC
- Annealed + Cold DrawnPick for close-tolerance bar, wire and shafting where slightly higher as-supplied strength and a better surface are needed before hardening.640 MPa yield · 26 HRC
Working with 440B Hardened + Cryo + Double Temper
Is 440B easy to machine?
Machine only in the annealed condition with rigid setups, sharp positive-rake carbide, low speed/heavy feed and flood coolant; hardened parts require grinding or EDM.
Can 440B be welded?
Poor weldability — preheat 200–300 °C, use matching or austenitic filler, and follow with a full anneal or hardening cycle to avoid HAZ cracking.
Can 440B be formed, bent or molded?
Only mild cold forming of annealed strip is practical; hot work at 1000–1150 °C with slow cooling and immediate anneal to prevent quench cracks.
What surface finishes work on 440B?
Harden, then grind and polish before final passivation; hardened surfaces take a mirror/edge finish, and hard chrome or nitriding is used only where extra wear life is needed.
440B 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 |
|---|---|---|
| Cdistinguishes 440B from 440A (0.60–0.75) and 440C (0.95–1.20) | 0.75 – 0.95 | 0.85 |
| Cr | 16 – 18 | 17 |
| Mn | ≤ 1 | 0.4 |
| Si | ≤ 1 | 0.4 |
| Momax; optional, aids hardenability | ≤ 0.75 | 0.4 |
| P | ≤ 0.04 | 0.02 |
| S | ≤ 0.03 | 0.01 |
| Fe | balance | — |
440B Hardened + Cryo + Double Temper — frequently asked
What is 440B Hardened + Cryo + Double Temper used for?
440B Hardened + Cryo + Double Temper is typically used for kitchen knife blades, pocket knife and folder blades, scissors and shear blades, valve seats and wear plates, bearing balls and races and surgical and dental instruments. In short: cutlery-grade hardenable stainless.
What is the yield strength of 440B Hardened + Cryo + Double Temper?
440B Hardened + Cryo + Double Temper has a typical yield strength of 1,700 MPa (247 ksi) and a tensile strength of 1,930 MPa (280 ksi) — stronger than 100% of stainless steel grades. Strength varies by condition: see the 5 listed tempers.
Is 440B Hardened + Cryo + Double Temper easy to machine?
Not especially — machinability is rated not recommended (6/100, worse than 100% of stainless steel grades). Machine only in the annealed condition with rigid setups, sharp positive-rake carbide, low speed/heavy feed and flood coolant; hardened parts require grinding or EDM.
Can 440B Hardened + Cryo + Double Temper be welded?
Not readily — weldability is rated poor (20/100). Poor weldability — preheat 200–300 °C, use matching or austenitic filler, and follow with a full anneal or hardening cycle to avoid HAZ cracking.
What surface finishes work on 440B Hardened + Cryo + Double Temper?
Harden, then grind and polish before final passivation; hardened surfaces take a mirror/edge finish, and hard chrome or nitriding is used only where extra wear life is needed.
Can 440B Hardened + Cryo + Double Temper be formed, bent or molded?
Only mild cold forming of annealed strip is practical; hot work at 1000–1150 °C with slow cooling and immediate anneal to prevent quench cracks.
What is the maximum service temperature of 440B Hardened + Cryo + Double Temper?
440B Hardened + Cryo + Double Temper is rated for continuous use to about 425°C (797 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Can FabDigit make parts in 440B Hardened + Cryo + Double Temper?
Yes — 440B Hardened + Cryo + Double Temper is available for CNC machining with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- ASTM A276/A276M Stainless Steel Bars and Shapes — ASTM (2023)
- EN 10088-3 (X90CrMoV18, 1.4112) — CEN (2014)
- JIS G 4303 (SUS440B) — JSA (2021)
- ASM Handbook Vol. 1: Properties and Selection — Irons, Steels — ASM International (1990)
- 440A/440B/440C Stainless Steel Product Data Sheet — AK Steel / Cleveland-Cliffs (2016)
- GB/T 1220 (9Cr18) — SAC (2007)
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.