Stainless Steel 1.4435 F138-CW
Supply condition
EN 1.4435
F138-CW = cold worked implant bar/wire
Implant-quality, low-inclusion, cold-worked condition for bone screws, plates and orthopaedic wire.
Values for the F138-CW condition
Other 1.4435 tempers and conditions
1.4435 is listed in 8 conditions; see the grade overview at 1.4435.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Hot rolled + solution annealed + pickled plate | Heavy plate condition for pressure vessels and tank shells; scale-free pickled surface. | 245 | 545 | 50 | 145 HB | 2.3 % IACS |
ANNDefault Annealed | Standard stocked condition for plate, sheet, tube and forgings — maximum corrosion resistance and formability. | 260 | 560 | 55 | 150 HB | — |
Cold drawn | Bar stock with tighter tolerances and ~2× the yield strength of annealed material for machined shafts and fittings. | 500 | 720 | 25 | 20 HRC | 2.3 % IACS |
Quarter hard | Light temper-rolled strip/sheet where extra yield strength is needed but some bending is still required. | 620 | 900 | 20 | 25 HRC | 2.3 % IACS |
Half hard | Medium temper strip for springy clips, clamps and structural strip where formability is limited. | 800 | 1,070 | 12 | 32 HRC | 2.3 % IACS |
F138-CWThis page Cold worked implant bar/wire | Implant-quality, low-inclusion, cold-worked condition for bone screws, plates and orthopaedic wire. | 800 | 1,000 | 18 | 30 HRC | 2.3 % IACS |
Three-quarter hard | High-strength strip for lightly formed spring and fastener parts. | 965 | 1,240 | 8 | 37 HRC | 2.3 % IACS |
Full hard | Maximum cold-worked strength for flat springs, shims and wire; essentially no bending capability across the grain. | 1,100 | 1,350 | 6 | 41 HRC | 2.3 % IACS |
What is 1.4435 F138-CW?
1.4435 F138-CW is 1.4435 supplied in the F138-CW condition — implant-quality, low-inclusion, cold-worked condition for bone screws, plates and orthopaedic wire. 1.4435 F138-CW has a yield strength of 800 MPa (116 ksi) and a tensile strength of 1,000 MPa (145 ksi) — stronger than 96% of stainless steel grades. Elongation at break is 18% and the elastic modulus is 195 GPa (28.3 Msi). 1.4435 F138-CW has a density of 8 g/cm³ (0.289 lb/in³), heavier than 92% of stainless steel grades. It melts at 1,390°C (2,534 °F). ANN is the default condition FabDigit quotes; F138-CW is available on request or by drawing note.
Advantages
- Polishes to a fine finish — 92/100, better than 100% of stainless steel grades
- High strength — 800 MPa (116 ksi), better than 96% of stainless steel grades
- Good corrosion resistance — 78/100, better than 84% of stainless steel grades
Limitations
- Limited service temperature — 300°C (572 °F), worse than 90% of stainless steel grades
- Limited ductility — 18%, worse than 83% of stainless steel grades
- High embodied carbon — 5.5 kg CO₂/kg, worse than 77% of stainless steel grades
1.4435 F138-CW properties
Typical room-temperature values for 1.4435 F138-CW; 24 are specific to this condition. Other listed values are 1.4435 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
1.4435 F138-CW has a density of 8 g/cm³ (0.289 lb/in³), heavier than 92% of stainless steel grades. It melts at 1,390°C (2,534 °F).
Mechanical16
1.4435 F138-CW has a yield strength of 800 MPa (116 ksi) and a tensile strength of 1,000 MPa (145 ksi) — stronger than 96% of stainless steel grades. Elongation at break is 18% and the elastic modulus is 195 GPa (28.3 Msi).
Thermal6
1.4435 F138-CW is rated for continuous service to 300°C (572 °F). It conducts heat at 15 W/m·K (8.67 BTU/hr·ft·°F), worse than 59% of stainless steel grades. Thermal expansion is 16 µm/m·K (8.89 µin/in·°F).
Electrical3
1.4435 F138-CW conducts electricity at 2.3 % IACS, better than 55% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is very good (78/100), better than 84% of stainless steel grades.
Sustainability4
Producing a kilogram of 1.4435 F138-CW takes about 57 MJ of energy and emits 5.5 kg of CO₂ — more than 62% of stainless steel grades. Typical recycled content is 60%.
Manufacturability7
1.4435 F138-CW's machinability is fair (42/100, better than 79% of stainless steel grades); weldability good (65/100); formability fair (35/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 1.4435 F138-CW
Is 1.4435 easy to machine?
Gummy and strongly work-hardening — use rigid setups, sharp positive-rake carbide, heavy constant feed, 60–120 m/min and copious high-pressure coolant; avoid dwelling.
Can 1.4435 be welded?
Excellent with GTAW/GMAW/plasma using 316L or 1.4430 filler (or autogenous for thin tube); no post-weld anneal needed thanks to C ≤0.03 %, back-purge with argon and pickle/passivate afterwards.
Can 1.4435 be formed, bent or molded?
Very good deep-drawing and bending, but high springback and rapid work hardening — allow intermediate solution anneals for severe multi-stage forming.
What surface finishes work on 1.4435?
Not anodizable; standard routes are pickling (HNO₃/HF), passivation to ASTM A967, mechanical polish to Ra ≤0.8 µm and electropolish to Ra ≤0.4 µm for pharma/ASME BPE service.
1.4435 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 |
|---|---|---|
| Clow carbon, resists sensitization | ≤ 0.03 | 0.02 |
| Si | ≤ 1 | 0.45 |
| Mn | ≤ 2 | 1.3 |
| P | ≤ 0.05 | 0.03 |
| Slower than 1.4404 for better weldability/polish | ≤ 0.02 | 0 |
| Cr | 17 – 19 | 17.5 |
| Nihigher than standard 316L for low ferrite | 12.5 – 15 | 13 |
| Mo | 2.5 – 3 | 2.7 |
| N | ≤ 0.11 | 0.05 |
| Fe | balance | — |
1.4435 F138-CW — frequently asked
What is 1.4435 F138-CW used for?
1.4435 F138-CW is typically used for surgical implants, food processing, cryogenic vessels and chemical piping. In short: implant-grade 316L variant; best weldability in family; cleanest electropolished finish.
What is the yield strength of 1.4435 F138-CW?
1.4435 F138-CW has a typical yield strength of 800 MPa (116 ksi) and a tensile strength of 1,000 MPa (145 ksi) — stronger than 96% of stainless steel grades. Strength varies by condition: see the 8 listed tempers.
Is 1.4435 F138-CW easy to machine?
Not especially — machinability is rated fair (42/100, better than 79% of stainless steel grades). Gummy and strongly work-hardening — use rigid setups, sharp positive-rake carbide, heavy constant feed, 60–120 m/min and copious high-pressure coolant; avoid dwelling.
Can 1.4435 F138-CW be welded?
Yes — weldability is rated good (65/100). Excellent with GTAW/GMAW/plasma using 316L or 1.4430 filler (or autogenous for thin tube); no post-weld anneal needed thanks to C ≤0.03 %, back-purge with argon and pickle/passivate afterwards.
What surface finishes work on 1.4435 F138-CW?
Not anodizable; standard routes are pickling (HNO₃/HF), passivation to ASTM A967, mechanical polish to Ra ≤0.8 µm and electropolish to Ra ≤0.4 µm for pharma/ASME BPE service.
Can 1.4435 F138-CW be formed, bent or molded?
Very good deep-drawing and bending, but high springback and rapid work hardening — allow intermediate solution anneals for severe multi-stage forming.
What is the maximum service temperature of 1.4435 F138-CW?
1.4435 F138-CW is rated for continuous use to about 300°C (572 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 1.4435-ANN and 1.4435-FH?
ANN is the default condition — standard stocked condition for plate, sheet, tube and forgings — maximum corrosion resistance and formability. FH: maximum cold-worked strength for flat springs, shims and wire; essentially no bending capability across the grain. Yield strength is 260 MPa in ANN versus 1,100 MPa in FH.
Sources
- EN 10088-1/-2/-3 Stainless steels — X2CrNiMo18-14-3 (1.4435) — CEN (2014)
- ASTM A240/A240M (UNS S31603) — ASTM (2023)
- ASTM A666 — annealed and cold-worked austenitic stainless sheet, strip, plate and bar — ASTM (2015)
- ASTM F138 / ISO 5832-1 — wrought 18Cr-14Ni-2.5Mo stainless for surgical implants — ASTM / ISO (2019)
- GB/T 20878 / GB/T 4237 — 022Cr17Ni14Mo2 — SAC (2015)
- Outokumpu Supra 316L/4435 datasheet and Corrosion Handbook — Outokumpu (2023)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- SMM / Mysteel (2025)
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.