Copper Alloy C50200-OS025
Temper
UNS C50200 · ASTM B103
OS025 = annealed to 0.025 mm grain size
Grain-size-controlled anneal for strip that must draw cleanly without orange peel.
Values for the OS025 condition
Other C50200 tempers and conditions
C50200 is listed in 9 conditions; see the grade overview at C50200.
Compare all 9 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Soft annealed | Maximum ductility for deep drawing, severe bending and spinning; lowest strength. | 95 | 275 | 45 | 25 HRB | 56 % IACS |
OS025This page Annealed to 0.025 mm grain size | Grain-size-controlled anneal for strip that must draw cleanly without orange peel. | 105 | 290 | 42 | 62 HB | 56 % IACS |
Quarter hard | Light cold work when moderate bending is still required after forming. | 250 | 325 | 25 | 95 HB | 55 % IACS |
H02Default Half hard | Default stocked strip temper: good balance of formability, strength and spring behaviour for terminals and clips. | 320 | 370 | 12 | 112 HB | 55 % IACS |
Full hard | Higher strength for flat springs and contacts with only gentle bends (large radii, bend across grain). | 390 | 420 | 6 | 130 HB | 54 % IACS |
Hard drawn | Cold-drawn rod/wire condition for cotter pins, wire forms and fasteners. | 400 | 450 | 8 | 140 HB | 54 % IACS |
Extra hard | Use where higher elastic limit is needed and forming is limited to simple flat blanking. | 425 | 455 | 4 | 145 HB | 54 % IACS |
Spring hard | Spring temper strip for contact fingers and washers; stress-relieve after forming to hold shape. | 460 | 490 | 3 | 158 HB | 53 % IACS |
Extra spring hard | Maximum cold-rolled strength for flat springs with essentially no forming other than blanking. | 490 | 515 | 2 | 168 HB | 53 % IACS |
What is C50200-OS025?
C50200-OS025 is C50200 in the OS025 temper — grain-size-controlled anneal for strip that must draw cleanly without orange peel. C50200-OS025 has a yield strength of 105 MPa (15.2 ksi) and a tensile strength of 290 MPa (42.1 ksi) — weaker than 85% of copper alloy grades. Elongation at break is 42% and the elastic modulus is 115 GPa (16.7 Msi). C50200-OS025 has a density of 8.89 g/cm³ (0.321 lb/in³), heavier than 72% of copper alloy grades. It melts at 1,060°C (1,940 °F). H02 is the default condition FabDigit quotes; OS025 is available on request or by drawing note.
Advantages
- Forms and bends easily — 92/100, better than 91% of copper alloy grades
- Ductile — tolerates forming and impact — 42%, better than 86% of copper alloy grades
- High electrical conductivity — 56 % IACS, better than 81% of copper alloy grades
- Conducts heat well — 218 W/m·K (126 BTU/hr·ft·°F), better than 80% of copper alloy grades
Limitations
- Limited service temperature — 150°C (302 °F), worse than 96% of copper alloy grades
- Difficult to machine — 25/100, worse than 86% of copper alloy grades
- Low strength — 105 MPa (15.2 ksi), worse than 85% of copper alloy grades
C50200-OS025 properties
Typical room-temperature values for C50200-OS025; 19 are specific to this condition. Other listed values are C50200 reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
C50200-OS025 has a density of 8.89 g/cm³ (0.321 lb/in³), heavier than 72% of copper alloy grades. It melts at 1,060°C (1,940 °F).
Mechanical15
C50200-OS025 has a yield strength of 105 MPa (15.2 ksi) and a tensile strength of 290 MPa (42.1 ksi) — weaker than 85% of copper alloy grades. Elongation at break is 42% and the elastic modulus is 115 GPa (16.7 Msi).
Thermal6
C50200-OS025 is rated for continuous service to 150°C (302 °F). It conducts heat at 218 W/m·K (126 BTU/hr·ft·°F), better than 80% of copper alloy grades. Thermal expansion is 17.8 µm/m·K (9.89 µin/in·°F).
Electrical3
C50200-OS025 conducts electricity at 56 % IACS, better than 81% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (65/100), better than 58% of copper alloy grades.
Sustainability4
Producing a kilogram of C50200-OS025 takes about 57 MJ of energy and emits 3.9 kg of CO₂ — less than 52% of copper alloy grades. Typical recycled content is 40%.
Manufacturability7
C50200-OS025's machinability is poor (25/100, worse than 86% of copper alloy grades); weldability good (55/100); formability excellent (92/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with C50200-OS025
Is C50200 easy to machine?
Machinability ~20% of free-cutting brass; gummy chips — use sharp positive-rake tools, high speed, light feeds and good lubrication.
Can C50200 be welded?
Excellent soldering and brazing; resistance and GTAW welding are fair — avoid overheating and use phosphor-bronze filler; oxyacetylene welding not recommended.
Can C50200 be formed, bent or molded?
Outstanding cold formability in O60/OS tempers (deep draw, severe bend); interanneal 480–650 °C for heavy reductions and stress-relieve formed springs at 180–200 °C.
What surface finishes work on C50200?
Takes tin, silver, nickel and gold plating readily; polishes well; no anodizing — protect against ammonia-bearing environments to avoid SCC in cold-worked tempers.
C50200 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 |
|---|---|---|
| Sn | 1 – 1.5 | 1.25 |
| Pdeoxidiser residual, kept low for conductivity | ≤ 0.04 | 0.03 |
| Feimpurity limit | ≤ 0.1 | — |
| Znimpurity limit | ≤ 0.3 | — |
| Pbimpurity limit | ≤ 0.05 | — |
| CuCu + named elements ≥ 99.5 %; Ag counted as Cu | ≥ 98 (balance) | — |
C50200-OS025 — frequently asked
What is C50200-OS025 used for?
C50200-OS025 is typically used for electrical contacts, switch blades, fasteners and cotter pins. In short: most formable phosphor bronze; low-cost spring bronze; good contact-plating base.
What is the yield strength of C50200-OS025?
C50200-OS025 has a typical yield strength of 105 MPa (15.2 ksi) and a tensile strength of 290 MPa (42.1 ksi) — weaker than 85% of copper alloy grades. Strength varies by condition: see the 9 listed tempers.
Is C50200-OS025 easy to machine?
Not especially — machinability is rated poor (25/100, worse than 86% of copper alloy grades). Machinability ~20% of free-cutting brass; gummy chips — use sharp positive-rake tools, high speed, light feeds and good lubrication.
Can C50200-OS025 be welded?
Yes — weldability is rated good (55/100). Excellent soldering and brazing; resistance and GTAW welding are fair — avoid overheating and use phosphor-bronze filler; oxyacetylene welding not recommended.
What surface finishes work on C50200-OS025?
Takes tin, silver, nickel and gold plating readily; polishes well; no anodizing — protect against ammonia-bearing environments to avoid SCC in cold-worked tempers.
Can C50200-OS025 be formed, bent or molded?
Outstanding cold formability in O60/OS tempers (deep draw, severe bend); interanneal 480–650 °C for heavy reductions and stress-relieve formed springs at 180–200 °C.
What is the maximum service temperature of C50200-OS025?
C50200-OS025 is rated for continuous use to about 150°C (302 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between C50200-H02 and C50200-O60?
H02 is the default condition — default stocked strip temper: good balance of formability, strength and spring behaviour for terminals and clips. O60: maximum ductility for deep drawing, severe bending and spinning; lowest strength. Yield strength is 320 MPa in H02 versus 95 MPa in O60.
Sources
- ASTM B103/B103M — Phosphor Bronze Plate, Sheet, Strip and Rolled Bar — ASTM International (2019)
- CDA Copper Alloy Datasheet C50200 — Copper Development Association (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.