Stainless Steel 1.4057
EN 1.4057 · UNS S43100 · AISI/SAE 431 · JIS SUS431 · GB 1Cr17Ni2
1.4057 (X17CrNi16-2, 431 / S43100, SUS431) is a chromium-nickel martensitic stainless in which about 2 % nickel raises toughness and corrosion resistance above the straight-chromium 410/420 grades.
Reference datasheet — 1.4057 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 +QT800 condition
1.4057 tempers and conditions
1.4057 is supplied in 6 conditions, soft to hard. +QT800 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 |
|---|---|---|---|---|---|---|
Annealed | Softest deliverable condition for machining, forming or as a base for subsequent hardening; still relatively hard because of the Ni content. | 600 | 800 | 20 | 24 HRC | — |
Quenched and tempered, Rm 700–850 MPa | High-temperature tempered condition for large sections or where maximum toughness and ductility are preferred over strength. | 600 | 780 | 18 | 22 HRC | — |
+QT800Default Quenched and tempered, Rm 800–950 MPa | Standard stocked bar condition: balanced strength, toughness and corrosion resistance for shafts, valve stems and fasteners. | 680 | 870 | 17 | 27 HRC | — |
Annealed and cold drawn bar | Cold-drawn ground/peeled bar for close tolerance and good surface finish before final hardening or for lightly loaded machined parts. | 720 | 900 | 12 | 29 HRC | 2.5 % IACS |
Quenched and tempered, Rm 900–1050 MPa | Higher-strength tempered condition for highly loaded shafts, bolts and pump components where some ductility can be traded for strength. | 780 | 970 | 15 | 31 HRC | — |
Hardened + low temper | Maximum hardness/wear resistance and best corrosion behaviour of the martensitic conditions; low toughness, use for cutlery-type edges, wear rings and small hardware. | 1,100 | 1,400 | 9 | 45 HRC | — |
What is 1.4057?
1.4057 (X17CrNi16-2, 431 / S43100, SUS431) is a chromium-nickel martensitic stainless in which about 2 % nickel raises toughness and corrosion resistance above the straight-chromium 410/420 grades. In the quenched and tempered condition it provides 680 MPa yield, 870 MPa tensile and 17 % elongation at roughly 270 HB (27 HRC), and is normally bought as bar for shafts, pins and high-strength fasteners. Machinability is modest (score 38), weldability is poor, the 450–550 °C temper embrittlement range must be avoided, and service is limited to about 500 °C. For higher strength with easier fabrication, consider 17-4 PH. 1.4057 has a density of 7.7 g/cm³ (0.278 lb/in³), lighter than 83% of stainless steel grades. It melts at 1,425°C (2,597 °F). 1.4057 has a yield strength of 680 MPa (98.6 ksi) and a tensile strength of 870 MPa (126 ksi) — stronger than 91% of stainless steel grades. Elongation at break is 17% and the elastic modulus is 215 GPa (31.2 Msi).
What is 1.4057 used for?
- aerospace shafts
- fasteners
- valve components
- pump shafts
Advantages
- Conducts heat well — 25 W/m·K (14.4 BTU/hr·ft·°F), better than 93% of stainless steel grades
- High strength — 680 MPa (98.6 ksi), better than 91% of stainless steel grades
- Low embodied carbon — 3.8 kg CO₂/kg, better than 77% of stainless steel grades
Limitations
- Difficult to weld — 30/100, worse than 88% of stainless steel grades
- Limited ductility — 17%, worse than 86% of stainless steel grades
- Limited formability — 20/100, worse than 86% of stainless steel grades
- Low fracture toughness — 75 MPa·√m (68.3 ksi·√in), worse than 81% of stainless steel grades
- Needs corrosion protection — 48/100, worse than 80% of stainless steel grades
1.4057 properties
Typical room-temperature values for 1.4057-+QT800; bars are the position among stainless steel grades.
Physical3
1.4057 has a density of 7.7 g/cm³ (0.278 lb/in³), lighter than 83% of stainless steel grades. It melts at 1,425°C (2,597 °F).
Mechanical16
1.4057 has a yield strength of 680 MPa (98.6 ksi) and a tensile strength of 870 MPa (126 ksi) — stronger than 91% of stainless steel grades. Elongation at break is 17% and the elastic modulus is 215 GPa (31.2 Msi).
Thermal6
1.4057 is rated for continuous service to 500°C (932 °F). It conducts heat at 25 W/m·K (14.4 BTU/hr·ft·°F), better than 93% of stainless steel grades. Thermal expansion is 10.5 µm/m·K (5.83 µin/in·°F).
Electrical3
1.4057 conducts electricity at 2.5 % IACS, better than 75% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is fair (48/100), worse than 80% of stainless steel grades.
Sustainability4
Producing a kilogram of 1.4057 takes about 55 MJ of energy and emits 3.8 kg of CO₂ — more than 50% of stainless steel grades. Typical recycled content is 60%.
Manufacturability7
1.4057's machinability is fair (38/100, better than 63% of stainless steel grades); weldability poor (30/100); 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. 1.4057 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 1.4057
Is 1.4057 easy to machine?
Machine in the annealed or ≤300 HB tempered condition with rigid setups, positive-rake carbide, 60–110 m/min and heavy feeds to cut under the work-hardened skin; flood coolant essential.
Can 1.4057 be welded?
Poor weldability — preheat 200–300 °C, use 309L/430 or matching filler, and temper at 650–700 °C immediately after welding to restore toughness; avoid welding in the fully hardened state.
Can 1.4057 be formed, bent or molded?
Hot work at 1100–850 °C with slow cooling; cold forming limited to gentle bends in the annealed state, hardening by oil/air quench from 980–1050 °C then temper (avoid 450–550 °C temper embrittlement range).
1.4057 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 |
|---|---|---|
| C | 0.12 – 0.22 | 0.17 |
| Si | ≤ 1 | 0.4 |
| Mn | ≤ 1.5 | 0.6 |
| P | ≤ 0.04 | |
| SEN 10088-3 limits S to 0.015 % for most product forms; free-machining versions are supplied with controlled S | ≤ 0.03 | |
| Cr | 15 – 17 | 16 |
| Ni | 1.5 – 2.5 | 2 |
| Mooptional/residual, restricted by some purchase specifications | ≤ 0.8 | |
| N | ≤ 0.06 | |
| Fe | balance |
What surface finishes work on 1.4057?
Takes a fine polish for shafting and decorative hardware; passivate per ASTM A967 after machining, and use hard chrome or electroless nickel where extra wear or chloride resistance is needed — no anodizing.
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 1.4057 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
How much does 1.4057 cost?
1.4057 is a standard-cost stainless steel ($$), cheaper than about 71% 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.
1.4057 — frequently asked
What is 1.4057 used for?
1.4057 is typically used for aerospace shafts, fasteners, valve components and pump shafts. In short: toughest martensitic stainless; best corrosion in 400-series; shaft-grade 431 equivalent.
What is the yield strength of 1.4057?
1.4057 has a typical yield strength of 680 MPa (98.6 ksi) and a tensile strength of 870 MPa (126 ksi) — stronger than 91% of stainless steel grades. Strength varies by condition: see the 6 listed tempers.
Is 1.4057 easy to machine?
Not especially — machinability is rated fair (38/100, better than 63% of stainless steel grades). Machine in the annealed or ≤300 HB tempered condition with rigid setups, positive-rake carbide, 60–110 m/min and heavy feeds to cut under the work-hardened skin; flood coolant essential.
Can 1.4057 be welded?
Not readily — weldability is rated poor (30/100). Poor weldability — preheat 200–300 °C, use 309L/430 or matching filler, and temper at 650–700 °C immediately after welding to restore toughness; avoid welding in the fully hardened state.
What surface finishes work on 1.4057?
Takes a fine polish for shafting and decorative hardware; passivate per ASTM A967 after machining, and use hard chrome or electroless nickel where extra wear or chloride resistance is needed — no anodizing.
Can 1.4057 be formed, bent or molded?
Hot work at 1100–850 °C with slow cooling; cold forming limited to gentle bends in the annealed state, hardening by oil/air quench from 980–1050 °C then temper (avoid 450–550 °C temper embrittlement range).
What is the maximum service temperature of 1.4057?
1.4057 is rated for continuous use to about 500°C (932 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does 1.4057 cost?
1.4057 is a standard-cost stainless steel ($$), cheaper than about 71% 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 10088-3 Stainless steels — semi-finished products, bars, rods, sections — CEN (2014)
- EN 10088-1 Stainless steels — List of stainless steels (physical properties) — CEN (2014)
- ASTM A276/A276M Stainless Steel Bars and Shapes (UNS S43100) — ASTM (2017)
- GB/T 1220 (1Cr17Ni2 / 14Cr17Ni2) — SAC (2007)
- JIS G 4303 Stainless steel bars (SUS431) — JSA (2021)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- Martensitic stainless bar datasheets (1.4057 / 431) — Outokumpu / Sandvik / Böhler (2023)
- 1Cr17Ni2 (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.