Copper Alloy Cu-OF1-OS050
Temper
EN CR007A
OS050 = annealed to 0.050 mm grain size
Grain-size-controlled anneal ordered when subsequent deep drawing, spinning or UHV bakeout behaviour must be reproducible.
Values for the OS050 condition
Other Cu-OF1 tempers and conditions
Cu-OF1 is listed in 6 conditions; see the grade overview at Cu-OF1.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Thermomechanically controlled processed | Unwrought oxygen-free cast stock per EN 1976, supplied for subsequent extrusion, rolling or drawing. | 55 | 170 | 35 | 40 HB | 101 % IACS |
OS050This page Annealed to 0.050 mm grain size | Grain-size-controlled anneal ordered when subsequent deep drawing, spinning or UHV bakeout behaviour must be reproducible. | 60 | 215 | 52 | 40 HB | 101 % IACS |
Soft annealed | Choose for maximum ductility, deep drawing, cold heading, gasket/seal rings and highest conductivity. | 65 | 220 | 50 | 42 HB | 101 % IACS |
Quarter hard | Light draw for straight, dimensionally stable rod that still bends and forms without cracking. | 180 | 260 | 30 | 68 HB | 100.8 % IACS |
Half hard | Best balance of strength, straightness and remaining ductility for machined electrical hardware and busbar terminals. | 230 | 300 | 20 | 85 HB | 100.5 % IACS |
H04Default Full hard | Standard stocked condition for straight OF copper rod — highest strength and best machining behaviour of the wrought tempers. | 300 | 350 | 12 | 95 HB | 100.2 % IACS |
What is Cu-OF1-OS050?
Cu-OF1-OS050 is Cu-OF1 in the OS050 temper — grain-size-controlled anneal ordered when subsequent deep drawing, spinning or UHV bakeout behaviour must be reproducible. Cu-OF1-OS050 has a yield strength of 60 MPa (8.7 ksi) and a tensile strength of 215 MPa (31.2 ksi) — weaker than 100% of copper alloy grades. Elongation at break is 52% and the elastic modulus is 125 GPa (18.1 Msi). Cu-OF1-OS050 has a density of 8.94 g/cm³ (0.323 lb/in³), heavier than 90% of copper alloy grades. It melts at 1,083°C (1,981 °F). H04 is the default condition FabDigit quotes; OS050 is available on request or by drawing note.
Advantages
- Conducts heat well — 394 W/m·K (227.6 BTU/hr·ft·°F), better than 100% of copper alloy grades
- High electrical conductivity — 101 % IACS, better than 98% of copper alloy grades
- Ductile — tolerates forming and impact — 52%, better than 97% of copper alloy grades
- Forms and bends easily — 97/100, better than 97% of copper alloy grades
- Polishes to a fine finish — 85/100, better than 92% of copper alloy grades
Limitations
- Low strength — 60 MPa (8.7 ksi), worse than 100% of copper alloy grades
Cu-OF1-OS050 properties
Typical room-temperature values for Cu-OF1-OS050; 10 are specific to this condition. Other listed values are Cu-OF1 reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
Cu-OF1-OS050 has a density of 8.94 g/cm³ (0.323 lb/in³), heavier than 90% of copper alloy grades. It melts at 1,083°C (1,981 °F).
Mechanical13
Cu-OF1-OS050 has a yield strength of 60 MPa (8.7 ksi) and a tensile strength of 215 MPa (31.2 ksi) — weaker than 100% of copper alloy grades. Elongation at break is 52% and the elastic modulus is 125 GPa (18.1 Msi).
Thermal6
Cu-OF1-OS050 is rated for continuous service to 250°C (482 °F). It conducts heat at 394 W/m·K (227.6 BTU/hr·ft·°F), better than 100% of copper alloy grades. Thermal expansion is 17 µm/m·K (9.44 µin/in·°F).
Electrical3
Cu-OF1-OS050 conducts electricity at 101 % IACS, better than 98% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (62/100), worse than 57% of copper alloy grades.
Sustainability4
Producing a kilogram of Cu-OF1-OS050 takes about 58 MJ of energy and emits 3.6 kg of CO₂ — more than 61% of copper alloy grades. Typical recycled content is 10%.
Manufacturability8
Cu-OF1-OS050's machinability is poor (27/100, worse than 81% of copper alloy grades); weldability good (68/100); formability excellent (97/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Cu-OF1-OS050
Is Cu-OF1 easy to machine?
Gummy and low-rated (~20 % of AISI 1212): use sharp positive-rake carbide or PCD, high speed, light-to-moderate feed and generous flood coolant; avoid dwelling to prevent smearing on UHV sealing faces.
Can Cu-OF1 be welded?
GTAW/EBW/laser weld readily with no risk of hydrogen ('steam') embrittlement, but the very high conductivity needs preheat 200–400 °C, high current and helium-rich shielding on thick sections.
Can Cu-OF1 be formed, bent or molded?
Outstanding cold formability in O60 — deep draw, spin, cold head and bend to tight radii; interanneal at 400–600 °C after heavy reduction, and expect softening of hard tempers above ~150 °C.
What surface finishes work on Cu-OF1?
Not anodisable; mirror-polishes and diamond-turns beautifully, and takes electroless/electrolytic Ni, Ag or Au plating — protect bare surfaces with benzotriazole or lacquer against tarnish.
Cu-OF1 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 |
|---|---|---|
| O≤5 ppm oxygen — no cuprous oxide network, hydrogen-embrittlement free | ≤ 5×10⁻⁴ | 3×10⁻⁴ |
| Agcounted within the Cu content | ≤ 0 | 0 |
| Bi | ≤ 5×10⁻⁴ | — |
| Pb | ≤ 5×10⁻⁴ | — |
| S | ≤ 0 | — |
| Se | ≤ 3×10⁻⁴ | — |
| Te | ≤ 2×10⁻⁴ | — |
| Pkept very low to preserve conductivity | ≤ 3×10⁻⁴ | — |
| Fe | ≤ 0 | — |
| Ni | ≤ 0 | — |
| Sn | ≤ 0 | — |
| Zn | ≤ 0 | — |
| total impuritiessum of named impurities excluding Ag and O | ≤ 0.01 | — |
| CuCu incl. Ag, min; oxygen-free refined cathode feed | ≥ 99.99 (balance) | — |
Cu-OF1-OS050 — frequently asked
What is Cu-OF1-OS050 used for?
Cu-OF1-OS050 is typically used for vacuum electronic components, high-purity electrical rod and welding electrode stock. In short: tightest-purity oxygen-free copper; no hydrogen embrittlement risk; 100.2 % IACS conductivity.
What is the yield strength of Cu-OF1-OS050?
Cu-OF1-OS050 has a typical yield strength of 60 MPa (8.7 ksi) and a tensile strength of 215 MPa (31.2 ksi) — weaker than 100% of copper alloy grades. Strength varies by condition: see the 6 listed tempers.
Is Cu-OF1-OS050 easy to machine?
Not especially — machinability is rated poor (27/100, worse than 81% of copper alloy grades). Gummy and low-rated (~20 % of AISI 1212): use sharp positive-rake carbide or PCD, high speed, light-to-moderate feed and generous flood coolant; avoid dwelling to prevent smearing on UHV sealing faces.
Can Cu-OF1-OS050 be welded?
Yes — weldability is rated good (68/100). GTAW/EBW/laser weld readily with no risk of hydrogen ('steam') embrittlement, but the very high conductivity needs preheat 200–400 °C, high current and helium-rich shielding on thick sections.
What surface finishes work on Cu-OF1-OS050?
Not anodisable; mirror-polishes and diamond-turns beautifully, and takes electroless/electrolytic Ni, Ag or Au plating — protect bare surfaces with benzotriazole or lacquer against tarnish.
Can Cu-OF1-OS050 be formed, bent or molded?
Outstanding cold formability in O60 — deep draw, spin, cold head and bend to tight radii; interanneal at 400–600 °C after heavy reduction, and expect softening of hard tempers above ~150 °C.
What is the maximum service temperature of Cu-OF1-OS050?
Cu-OF1-OS050 is rated for continuous use to about 250°C (482 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between Cu-OF1-H04 and Cu-OF1-M?
H04 is the default condition — standard stocked condition for straight OF copper rod — highest strength and best machining behaviour of the wrought tempers. M: unwrought oxygen-free cast stock per EN 1976, supplied for subsequent extrusion, rolling or drawing. Yield strength is 300 MPa in H04 versus 55 MPa in M.
Sources
- EN 1976 — Copper and copper alloys: cast unwrought copper products — CEN (2012)
- EN 13601 — Copper rod, bar and wire for general electrical purposes — CEN (2021)
- EN 1173 — Material condition (temper) designations — CEN (2008)
- ASTM B170 — Oxygen-Free Electrolytic Copper Refinery Shapes — ASTM (2019)
- C10100 / C10200 alloy datasheets — Copper Development Association (copper.org) (2023)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
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.