Cobalt-Chrome Alloy F90 Cold Worked
Supply condition
ASTM F90
Choose when higher strength and fatigue capability are needed and the part needs little further forming (bar, strip, springs, stent tubing).
Values for the Cold Worked condition
Other F90 tempers and conditions
F90 is listed in 2 conditions; see the grade overview at F90.
- Solution Annealed
- Cold Worked
Compare all 2 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution AnnealedDefault 1180–1230 °C, rapid cool | Standard stocked condition: maximum ductility and corrosion resistance for forming, machining and welding before final processing. | 460 | 1,000 | 55 | 240 HB | — |
Cold WorkedThis page cold reduced (approx. 20–40 %) per ASTM F90 cold-worked condition | Choose when higher strength and fatigue capability are needed and the part needs little further forming (bar, strip, springs, stent tubing). | 1,200 | 1,500 | 15 | 44 HRC | — |
What is F90 Cold Worked?
F90 Cold Worked is F90 supplied in the Cold Worked condition — choose when higher strength and fatigue capability are needed and the part needs little further forming (bar, strip, springs, stent tubing). F90 Cold Worked has a yield strength of 1,200 MPa (174 ksi) and a tensile strength of 1,500 MPa (218 ksi) — stronger than 88% of cobalt-chrome alloy grades. Elongation at break is 15% and the elastic modulus is 225 GPa (32.6 Msi). F90 Cold Worked has a density of 9.13 g/cm³ (0.33 lb/in³), heavier than 98% of cobalt-chrome alloy grades. It melts at 1,330°C (2,426 °F). Solution Annealed is the default condition FabDigit quotes; Cold Worked is available on request or by drawing note.
Advantages
- Tough — resists crack growth — 100 MPa·√m (91 ksi·√in), better than 97% of cobalt-chrome alloy grades
- High strength — 1,200 MPa (174 ksi), better than 88% of cobalt-chrome alloy grades
- Forms and bends easily — 25/100, better than 82% of cobalt-chrome alloy grades
- Readily welded — 55/100, better than 80% of cobalt-chrome alloy grades
Limitations
- Limited service temperature — 400°C (752 °F), worse than 96% of cobalt-chrome alloy grades
- Poor heat conductor — 9.6 W/m·K (5.55 BTU/hr·ft·°F), worse than 96% of cobalt-chrome alloy grades
- High embodied carbon — 18 kg CO₂/kg, worse than 93% of cobalt-chrome alloy grades
F90 Cold Worked properties
Typical room-temperature values for F90 Cold Worked; 12 are specific to this condition. Other listed values are F90 reference data and may not represent this condition. Bars are the position among cobalt-chrome alloy grades.
Physical3
F90 Cold Worked has a density of 9.13 g/cm³ (0.33 lb/in³), heavier than 98% of cobalt-chrome alloy grades. It melts at 1,330°C (2,426 °F).
Mechanical15
F90 Cold Worked has a yield strength of 1,200 MPa (174 ksi) and a tensile strength of 1,500 MPa (218 ksi) — stronger than 88% of cobalt-chrome alloy grades. Elongation at break is 15% and the elastic modulus is 225 GPa (32.6 Msi).
Thermal6
F90 Cold Worked is rated for continuous service to 400°C (752 °F). It conducts heat at 9.6 W/m·K (5.55 BTU/hr·ft·°F), worse than 96% of cobalt-chrome alloy grades. Thermal expansion is 12.3 µm/m·K (6.83 µin/in·°F).
Electrical3
F90 Cold Worked conducts electricity at 1.9 % IACS, worse than 52% of cobalt-chrome alloy grades.
Chemical & Environmental3
Corrosion resistance is very good (84/100), better than 75% of cobalt-chrome alloy grades.
Sustainability4
Producing a kilogram of F90 Cold Worked takes about 250 MJ of energy and emits 18 kg of CO₂ — more than 95% of cobalt-chrome alloy grades. Typical recycled content is 25%.
Manufacturability7
F90 Cold Worked's machinability is not recommended (12/100, better than 61% of cobalt-chrome alloy grades); weldability good (55/100); formability poor (25/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with F90 Cold Worked
Is F90 easy to machine?
Very difficult: rigid setups, positive-rake carbide or ceramic tools, low speed with heavy feed, flood coolant and no dwelling to avoid rapid work hardening.
Can F90 be welded?
GTAW, plasma, laser and electron-beam welding are used with matched L-605 filler; keep heat input low, no preheat, and solution anneal after welding for best ductility and corrosion resistance.
Can F90 be formed, bent or molded?
Form in the solution-annealed condition with generous radii and high forming loads; work-hardening rate is high so intermediate anneals at 1180–1230 °C are usually needed.
What surface finishes work on F90?
Electropolishing and passivation per ASTM F86 give an implant-quality surface; takes a high mirror polish, and can be PVD coated but not anodized.
F90 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 |
|---|---|---|
| Cr | 19 – 21 | 20 |
| W | 14 – 16 | 15 |
| Ni | 9 – 11 | 10 |
| Fe | ≤ 3 | 1.5 |
| Mn | 1 – 2 | 1.5 |
| C | 0.05 – 0.15 | 0.1 |
| Si | ≤ 0.4 | 0.2 |
| P | ≤ 0.04 | |
| S | ≤ 0.03 | |
| Cobalance, nominally ~50 % | balance |
F90 Cold Worked — frequently asked
What is F90 Cold Worked used for?
F90 Cold Worked is typically used for vascular stents and guidewires, orthopaedic and spinal implants, dental components, gas turbine combustion chamber parts, high-temperature springs and high-temperature fasteners. In short: wrought biomedical cobalt.
What is the yield strength of F90 Cold Worked?
F90 Cold Worked has a typical yield strength of 1,200 MPa (174 ksi) and a tensile strength of 1,500 MPa (218 ksi) — stronger than 88% of cobalt-chrome alloy grades. Strength varies by condition: see the 2 listed tempers.
Is F90 Cold Worked easy to machine?
Not especially — machinability is rated not recommended (12/100, better than 61% of cobalt-chrome alloy grades). Very difficult: rigid setups, positive-rake carbide or ceramic tools, low speed with heavy feed, flood coolant and no dwelling to avoid rapid work hardening.
Can F90 Cold Worked be welded?
Yes — weldability is rated good (55/100). GTAW, plasma, laser and electron-beam welding are used with matched L-605 filler; keep heat input low, no preheat, and solution anneal after welding for best ductility and corrosion resistance.
What surface finishes work on F90 Cold Worked?
Electropolishing and passivation per ASTM F86 give an implant-quality surface; takes a high mirror polish, and can be PVD coated but not anodized.
Can F90 Cold Worked be formed, bent or molded?
Form in the solution-annealed condition with generous radii and high forming loads; work-hardening rate is high so intermediate anneals at 1180–1230 °C are usually needed.
What is the maximum service temperature of F90 Cold Worked?
F90 Cold Worked 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 F90 Cold Worked?
Yes — F90 Cold Worked is available for CNC machining and sheet metal with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- ASTM F90 — Standard Specification for Wrought Cobalt-20Chromium-15Tungsten-10Nickel Alloy for Surgical Implant Applications — ASTM International (2021)
- HAYNES 25 alloy (L-605) technical data — Haynes International (2020)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials — ASM International (1990)
- ASM Handbook Vol.19 — Fatigue and Fracture — ASM International (1996)
- ASTM F86 — Surface Preparation and Marking of Metallic Surgical Implants — ASTM International (2021)
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.