Stainless Steel 1.3956
EN 1.3956
1.3956 (GX4CrNiMnN22-12-5) is a manganese- and nitrogen-alloyed austenitic casting steel with 22Cr-12Ni-5Mn, used where cryogenic toughness and low magnetic permeability are required.
Reference datasheet — 1.3956 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 AT condition
1.3956 tempers and conditions
1.3956 is supplied in 3 conditions, soft to hard. AT is the default FabDigit quotes; the values on this page are for it.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
ATDefault Solution annealed | Standard delivery condition: maximum toughness, lowest permeability and best corrosion resistance — use for all cryogenic and non-magnetic service. | 340 | 660 | 35 | 195 HB | — |
Hot isostatically pressed then solution annealed | Pick for pressure-retaining or fatigue-loaded cryogenic castings where microporosity must be eliminated (radiographic Level 1). | 350 | 690 | 42 | 195 HB | 2 % IACS |
As fabricated | Rough/unfinished condition only — interdendritic carbo-nitrides raise hardness but cut toughness, corrosion resistance and magnetic purity; not for cryogenic or corrosive duty. | 360 | 620 | 18 | 17 HRC | 2 % IACS |
Supply forms, finishes and certifications
Ways 1.3956 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
AT-CRYO | Solution annealed with cryogenic impact qualification | Certification |
What is 1.3956?
1.3956 (GX4CrNiMnN22-12-5) is a manganese- and nitrogen-alloyed austenitic casting steel with 22Cr-12Ni-5Mn, used where cryogenic toughness and low magnetic permeability are required. Nitrogen strengthening raises the solution-annealed properties to 340 MPa yield, 660 MPa tensile, 35 % elongation and 195 HB, with service to 550 °C and a corrosion score of 68. The trade-off is machinability — it work-hardens like Nitronic 50 — and parts must be solution annealed and water quenched before service; standard CF8/CF3 castings are cheaper where non-magnetic behaviour is not required. 1.3956 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 59% of stainless steel grades. It melts at 1,400°C (2,552 °F). 1.3956 has a yield strength of 340 MPa (49.3 ksi) and a tensile strength of 660 MPa (95.7 ksi) — weaker than 55% of stainless steel grades. Elongation at break is 35% and the elastic modulus is 196 GPa (28.4 Msi).
What is 1.3956 used for?
- cryogenic valve bodies
- non-magnetic fittings
- low-temperature process castings
Advantages
- Tough — resists crack growth — 190 MPa·√m (172.9 ksi·√in), better than 77% of stainless steel grades
Limitations
- Limited formability — 20/100, worse than 86% of stainless steel grades
- Hard to polish — 60/100, worse than 80% of stainless steel grades
- Low electrical conductivity — 2 % IACS, worse than 77% of stainless steel grades
1.3956 properties
Typical room-temperature values for 1.3956-AT; bars are the position among stainless steel grades.
Physical3
1.3956 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 59% of stainless steel grades. It melts at 1,400°C (2,552 °F).
Mechanical16
1.3956 has a yield strength of 340 MPa (49.3 ksi) and a tensile strength of 660 MPa (95.7 ksi) — weaker than 55% of stainless steel grades. Elongation at break is 35% and the elastic modulus is 196 GPa (28.4 Msi).
Thermal6
1.3956 is rated for continuous service to 550°C (1,022 °F). It conducts heat at 14 W/m·K (8.09 BTU/hr·ft·°F), worse than 80% of stainless steel grades. Thermal expansion is 16.5 µm/m·K (9.17 µin/in·°F).
Electrical3
1.3956 conducts electricity at 2 % IACS, worse than 77% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (68/100), better than 63% of stainless steel grades.
Sustainability4
Producing a kilogram of 1.3956 takes about 55 MJ of energy and emits 4.5 kg of CO₂ — more than 50% of stainless steel grades. Typical recycled content is 65%.
Manufacturability7
1.3956's machinability is poor (28/100, worse than 79% of stainless steel grades); weldability very good (70/100); formability poor (20/100).
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. 1.3956 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 1.3956
Is 1.3956 easy to machine?
Treat like Nitronic 50: rigid setups, sharp positive-rake carbide/ceramic, heavy constant feed and flood coolant — light cuts glaze and work-harden the surface; expect ~30 % of 1212 rates.
Can 1.3956 be welded?
Readily welded by GTAW/GMAW/SMAW with matching 22-12-5 high-N or 209/240-type filler, no preheat, interpass <150 °C; re-solution anneal heavy repairs to restore toughness and low permeability.
Can 1.3956 be formed, bent or molded?
Foundry grade — use generous risering for the long freezing range, avoid N loss in the melt, and always solution anneal + water quench before machining or service.
1.3956 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 |
|---|---|---|
| CGX4 = ~0.04 % C nominal | ≤ 0.06 | 0.04 |
| Si | ≤ 1 | 0.6 |
| Mnraises N solubility, stabilises austenite | 4 – 6 | 5 |
| P | ≤ 0.04 | |
| S | ≤ 0.03 | |
| Cr | 21 – 23 | 22 |
| Ni | 11 – 13 | 12 |
| Moresidual unless specially ordered | ≤ 0.5 | |
| Nprincipal solid-solution strengthener | 0.15 – 0.3 | 0.22 |
| Fe | balance |
What surface finishes work on 1.3956?
Pickle and passivate after heat treatment to remove the Cr/N-rich scale; grinds and polishes well but casting porosity limits mirror finishes; do not use ferritic grinding media on non-magnetic parts.
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 1.3956 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- EN / DIN / Werkstoff-Nr.
- GX4CrNiMnN22-12-5
How much does 1.3956 cost?
1.3956 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.
1.3956 — frequently asked
What is 1.3956 used for?
1.3956 is typically used for cryogenic valve bodies, non-magnetic fittings and low-temperature process castings. In short: non-magnetic cast austenitic; cryogenic toughness; nitrogen-strengthened, 340 MPa yield.
What is the yield strength of 1.3956?
1.3956 has a typical yield strength of 340 MPa (49.3 ksi) and a tensile strength of 660 MPa (95.7 ksi) — weaker than 55% of stainless steel grades. Strength varies by condition: see the 3 listed tempers.
Is 1.3956 easy to machine?
Not especially — machinability is rated poor (28/100, worse than 79% of stainless steel grades). Treat like Nitronic 50: rigid setups, sharp positive-rake carbide/ceramic, heavy constant feed and flood coolant — light cuts glaze and work-harden the surface; expect ~30 % of 1212 rates.
Can 1.3956 be welded?
Yes — weldability is rated very good (70/100). Readily welded by GTAW/GMAW/SMAW with matching 22-12-5 high-N or 209/240-type filler, no preheat, interpass <150 °C; re-solution anneal heavy repairs to restore toughness and low permeability.
What surface finishes work on 1.3956?
Pickle and passivate after heat treatment to remove the Cr/N-rich scale; grinds and polishes well but casting porosity limits mirror finishes; do not use ferritic grinding media on non-magnetic parts.
Can 1.3956 be formed, bent or molded?
Foundry grade — use generous risering for the long freezing range, avoid N loss in the melt, and always solution anneal + water quench before machining or service.
What is the maximum service temperature of 1.3956?
1.3956 is rated for continuous use to about 550°C (1,022 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 1.3956-AT and 1.3956-F?
AT is the default condition — standard delivery condition: maximum toughness, lowest permeability and best corrosion resistance — use for all cryogenic and non-magnetic service. F: rough/unfinished condition only — interdendritic carbo-nitrides raise hardness but cut toughness, corrosion resistance and magnetic purity; not for cryogenic or corrosive duty. Yield strength is 340 MPa in AT versus 360 MPa in F.
How much does 1.3956 cost?
1.3956 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
- EN 10213 — Steel castings for pressure purposes — CEN (2016)
- SEW 410 / DIN 17445 — Stainless and non-magnetic steel castings — VDEh / DIN (1998)
- ASTM A743/A743M (CG6MMN, comparable cast 22-12-5 N grade) — ASTM (2021)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.19 — Fatigue and Fracture — ASM International (1996)
- Non-magnetic austenitic stainless steel castings (22Cr-12Ni-5Mn-N) data — Steel foundry datasheets (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.