Stainless Steel 431 Cold Drawn
Supply condition
AISI/SAE 431 · UNS S43100 · EN 1.4057, X17CrNi16-2 · JIS SUS431 · GB 17Cr16Ni2, 1Cr17Ni2
Precision-size bar with improved straightness and surface for machined parts that will not be re-heat-treated.
Values for the Cold Drawn condition
Other 431 tempers and conditions
431 is listed in 8 conditions; see the grade overview at 431.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
EN 10088-3 quenched and tempered, Rm 700–850 MPa | Lowest-strength QT class in EN 10088-3; pick for large sections or where machining and toughness matter more than strength. | 540 | 770 | 16 | 22 HRC | 2.4 % IACS |
EN 10088-3 quenched and tempered, Rm 800–950 MPa | Common European bar condition for pump/valve shafts, KV ≥ 20 J with good corrosion resistance. | 650 | 870 | 15 | 27 HRC | 2.4 % IACS |
Condition A / EN +A (soft annealed bar, sheet) | Stock condition for machining and subsequent heat treatment; note 431 is still quite strong when annealed because it air-hardens. | 655 | 830 | 22 | 26 HRC | — |
EN 10088-3 quenched and tempered, Rm 900–1050 MPa | Highest standard EN QT class; use where strength governs and impact requirement is modest (KV ≥ 15 J). | 750 | 970 | 13 | 31 HRC | 2.4 % IACS |
Hardened & TemperedDefault oil/air quench + high temper (~600–650 °C), 28–34 HRC | The normal supply and service condition: best balance of strength, toughness and corrosion resistance for shafts, stems and fasteners. | 760 | 950 | 16 | 31 HRC | — |
Cold DrawnThis page Cold Drawn (annealed + cold drawn bar/wire) | Precision-size bar with improved straightness and surface for machined parts that will not be re-heat-treated. | 760 | 930 | 12 | 30 HRC | 2.4 % IACS |
Hardened & low-temper | Maximum-strength/wear condition for stems, bushings and cutlery-type parts; accept low impact toughness and no notches. | 1,080 | 1,330 | 10 | 42 HRC | — |
45–48 HRC | Intermediate state only — must be tempered before use; retained stresses make it crack-prone. | 1,200 | 1,500 | 5 | 46 HRC | 2.3 % IACS |
What is 431 Cold Drawn?
431 Cold Drawn is 431 supplied in the Cold Drawn condition — precision-size bar with improved straightness and surface for machined parts that will not be re-heat-treated. 431 Cold Drawn has a yield strength of 760 MPa (110 ksi) and a tensile strength of 930 MPa (135 ksi) — stronger than 94% of stainless steel grades. Elongation at break is 12% and the elastic modulus is 200 GPa (29 Msi). 431 Cold Drawn has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 65% of stainless steel grades. It melts at 1,425°C (2,597 °F). Hardened & Tempered is the default condition FabDigit quotes; Cold Drawn is available on request or by drawing note.
Advantages
- High strength — 760 MPa (110 ksi), better than 94% of stainless steel grades
Limitations
- Limited ductility — 12%, worse than 95% of stainless steel grades
- Difficult to weld — 25/100, worse than 92% 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
431 Cold Drawn properties
Typical room-temperature values for 431 Cold Drawn; 22 are specific to this condition. Other listed values are 431 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
431 Cold Drawn has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 65% of stainless steel grades. It melts at 1,425°C (2,597 °F).
Mechanical16
431 Cold Drawn has a yield strength of 760 MPa (110 ksi) and a tensile strength of 930 MPa (135 ksi) — stronger than 94% of stainless steel grades. Elongation at break is 12% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
431 Cold Drawn is rated for continuous service to 400°C (752 °F). It conducts heat at 20.2 W/m·K (11.7 BTU/hr·ft·°F), better than 74% of stainless steel grades. Thermal expansion is 11.7 µm/m·K (6.5 µin/in·°F).
Electrical3
431 Cold Drawn conducts electricity at 2.4 % IACS, better than 67% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is fair (48/100), worse than 80% of stainless steel grades.
Sustainability4
Producing a kilogram of 431 Cold Drawn 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
431 Cold Drawn's machinability is fair (40/100, better than 72% of stainless steel grades); weldability poor (25/100); formability poor (20/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 431 Cold Drawn
Is 431 easy to machine?
Machine in the annealed or ≤32 HRC condition with rigid setups, sharp carbide, positive rake, heavy flood coolant and constant feed to avoid work hardening; expect ~40 % of 1212 and use ground/turned bar for finish-critical diameters.
Can 431 be welded?
Best avoided — air-hardening HAZ cracks readily; if required, preheat 200–300 °C, use 309/310 or matching 431 filler, weld hot and immediately post-weld temper at 620–650 °C, then slow cool.
Can 431 be formed, bent or molded?
Hot work 1150–900 °C then slow cool/anneal; cold forming is limited to gentle bends in the annealed state, and all forming should be done before hardening.
What surface finishes work on 431?
Passivate per ASTM A967 after machining/grinding; polishes to a bright finish and takes hard chrome, electroless nickel or nitriding — do not bake or plate-relieve in the 370–570 °C embrittlement window.
431 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 |
|---|---|---|
| CASTM A276 S43100: 0.20 max; EN 1.4057: 0.12–0.22 | 0.12 – 0.2 | 0.17 |
| Si | ≤ 1 | 0.5 |
| Mn | ≤ 1 | 0.6 |
| P | ≤ 0.04 | 0.03 |
| SEN 1.4057 S ≤ 0.015; free-machining sulphurised versions (BS 431S29 type) run higher | ≤ 0.03 | 0.02 |
| Cr | 15 – 17 | 16 |
| NiEN 1.4057: 1.5–2.5 | 1.25 – 2.5 | 2 |
| Monot specified in ASTM; EN permits residual Mo ≤ 0.8 | ≤ 0.8 | — |
| Fe | balance | — |
431 Cold Drawn — frequently asked
What is 431 Cold Drawn used for?
431 Cold Drawn is typically used for marine propeller and rudder shafts, pump and mixer shafts, high-strength bolts and studs, valve stems and spindles, steam and gas turbine blades and aerospace fittings and linkages. In short: high-strength martensitic shafting.
What is the yield strength of 431 Cold Drawn?
431 Cold Drawn has a typical yield strength of 760 MPa (110 ksi) and a tensile strength of 930 MPa (135 ksi) — stronger than 94% of stainless steel grades. Strength varies by condition: see the 8 listed tempers.
Is 431 Cold Drawn easy to machine?
Not especially — machinability is rated fair (40/100, better than 72% of stainless steel grades). Machine in the annealed or ≤32 HRC condition with rigid setups, sharp carbide, positive rake, heavy flood coolant and constant feed to avoid work hardening; expect ~40 % of 1212 and use ground/turned bar for finish-critical diameters.
Can 431 Cold Drawn be welded?
Not readily — weldability is rated poor (25/100). Best avoided — air-hardening HAZ cracks readily; if required, preheat 200–300 °C, use 309/310 or matching 431 filler, weld hot and immediately post-weld temper at 620–650 °C, then slow cool.
What surface finishes work on 431 Cold Drawn?
Passivate per ASTM A967 after machining/grinding; polishes to a bright finish and takes hard chrome, electroless nickel or nitriding — do not bake or plate-relieve in the 370–570 °C embrittlement window.
Can 431 Cold Drawn be formed, bent or molded?
Hot work 1150–900 °C then slow cool/anneal; cold forming is limited to gentle bends in the annealed state, and all forming should be done before hardening.
What is the maximum service temperature of 431 Cold Drawn?
431 Cold Drawn is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Can FabDigit make parts in 431 Cold Drawn?
Yes — 431 Cold Drawn is available for CNC machining and sheet metal; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.
Sources
- ASTM A276/A276M — Stainless Steel Bars and Shapes — ASTM International (2023)
- ASTM A582/A582M — Free-Machining Stainless Steel Bars — ASTM International (2021)
- EN 10088-3 — Stainless steels: semi-finished products, bars, rods (X17CrNi16-2, 1.4057) — CEN (2014)
- AMS 5628 — Steel Bars, Forgings, 16Cr–2.0Ni — SAE International (2018)
- GB/T 1220 — (14Cr17Ni2) — SAC (2007)
- ASM Handbook Vol. 1: Properties and Selection — Irons, Steels and High-Performance Alloys — ASM International (1990)
- Martensitic stainless steel 1.4057/431 bar datasheet — European long-product mill (typical values) (2022)
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.