Cobalt-Chrome Alloy F90 · supply condition
Cobalt-Chrome Alloy F90 Cold Worked Hard Wire
Properties of the Cold Worked Hard Wire condition, compared with the other F90 tempers.
Highest-strength condition for guidewires, springs and fine wire where ductility can be sacrificed.
What is F90 Cold Worked Hard Wire?
F90 Cold Worked Hard Wire is F90 supplied in the Cold Worked Hard Wire condition — highest-strength condition for guidewires, springs and fine wire where ductility can be sacrificed. F90 Cold Worked Hard Wire has a yield strength of 1,650 MPa (239 ksi) and a tensile strength of 1,900 MPa (276 ksi) — stronger than 87% of cobalt-chrome alloy grades. Elongation at break is 5% and the elastic modulus is 225 GPa (32.6 Msi). F90 Cold Worked Hard Wire 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 Hard Wire 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 — 1,650 MPa (239 ksi), better than 87% of cobalt-chrome alloy grades
Limitations
- Limited service temperature — 350°C (662 °F), worse than 100% of cobalt-chrome alloy grades
- Poor heat conductor — 9.6 W/m·K (5.55 BTU/hr·ft·°F), worse than 97% of cobalt-chrome alloy grades
- High embodied carbon — 18 kg CO₂/kg, worse than 90% of cobalt-chrome alloy grades
F90 Cold Worked Hard Wire properties
Typical room-temperature values for F90 Cold Worked Hard Wire — 10 properties are specific to this condition; the rest are grade-level values shared by every F90 temper. Each bar shows where the value sits among the cobalt-chrome alloy grades in FabDigit's library — further right is higher.
Physical3
F90 Cold Worked Hard Wire 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 Hard Wire has a yield strength of 1,650 MPa (239 ksi) and a tensile strength of 1,900 MPa (276 ksi) — stronger than 87% of cobalt-chrome alloy grades. Elongation at break is 5% and the elastic modulus is 225 GPa (32.6 Msi).
Thermal6
F90 Cold Worked Hard Wire is rated for continuous service to 350°C (662 °F). It conducts heat at 9.6 W/m·K (5.55 BTU/hr·ft·°F), worse than 97% of cobalt-chrome alloy grades. Thermal expansion is 12.3 µm/m·K (6.83 µin/in·°F).
Electrical3
F90 Cold Worked Hard Wire conducts electricity at 1.9 % IACS, worse than 54% of cobalt-chrome alloy grades.
Chemical & Environmental3
Corrosion resistance is very good (84/100), better than 72% of cobalt-chrome alloy grades.
Sustainability4
Producing a kilogram of F90 Cold Worked Hard Wire takes about 250 MJ of energy and emits 18 kg of CO₂ — more than 91% of cobalt-chrome alloy grades. Typical recycled content is 25%.
Manufacturability7
F90 Cold Worked Hard Wire's machinability is not recommended (10/100, better than 53% of cobalt-chrome alloy grades); weldability fair (45/100); formability not recommended (12/100).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other F90 tempers and conditions
F90 is also supplied in 3 other conditions. The full side-by-side table is on the F90 overview.
- Solution AnnealedDefaultStandard stocked condition: maximum ductility and corrosion resistance for forming, machining and welding before final processing.460 MPa yield · 240 HB
- Cold Worked Hard WireHighest-strength condition for guidewires, springs and fine wire where ductility can be sacrificed.1,650 MPa yield · 51 HRC
- Cold WorkedChoose when higher strength and fatigue capability are needed and the part needs little further forming (bar, strip, springs, stent tubing).1,200 MPa yield · 44 HRC
Working with F90 Cold Worked Hard Wire
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 Hard Wire — frequently asked
What is F90 Cold Worked Hard Wire used for?
F90 Cold Worked Hard Wire 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 Hard Wire?
F90 Cold Worked Hard Wire has a typical yield strength of 1,650 MPa (239 ksi) and a tensile strength of 1,900 MPa (276 ksi) — stronger than 87% of cobalt-chrome alloy grades. Strength varies by condition: see the 4 listed tempers.
Is F90 Cold Worked Hard Wire easy to machine?
Not especially — machinability is rated not recommended (10/100, better than 53% 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 Hard Wire be welded?
With care — weldability is rated fair (45/100). 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 Hard Wire?
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 Hard Wire 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 Hard Wire?
F90 Cold Worked Hard Wire is rated for continuous use to about 350°C (662 °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 Hard Wire?
Yes — F90 Cold Worked Hard Wire 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.