Copper Alloy C40500-OS035
Temper
UNS C40500
OS035 = annealed to 0.035 mm grain size
Softest commercial strip temper — pick for deep drawing, severe coining and heavy forming.
Values for the OS035 condition
Other C40500 tempers and conditions
C40500 is listed in 9 conditions; see the grade overview at C40500.
Compare all 9 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
OS035This page Annealed to 0.035 mm grain size | Softest commercial strip temper — pick for deep drawing, severe coining and heavy forming. | 105 | 275 | 45 | 60 HB | 41 % IACS |
Annealed to 0.015 mm grain size | Fine-grain anneal for formed parts needing a smooth, orange-peel-free surface after drawing. | 125 | 305 | 42 | 72 HB | 41 % IACS |
Quarter hard | Light temper for parts still needing bending/forming but stiffer than annealed stock. | 275 | 330 | 28 | 100 HB | 40 % IACS |
H02Default Half hard | The general-purpose stocked strip temper — balanced strength and bendability for stampings and contacts. | 330 | 385 | 12 | 120 HB | 40 % IACS |
Three-quarter hard | Use where higher stiffness is needed and only gentle, large-radius bends are required. | 370 | 420 | 8 | 133 HB | 40 % IACS |
Full hard | Standard hard strip for flat stampings, washers and blanked coin-type parts with little forming. | 400 | 455 | 5 | 145 HB | 39 % IACS |
Extra hard | High-strength flat stock for flat springs and clips formed only across the rolling direction. | 450 | 505 | 3 | 158 HB | 39 % IACS |
Spring hard | Spring-tempered strip for contacts and leaf springs needing high elastic limit; watch SCC in ammonia. | 480 | 540 | 3 | 168 HB | 38 % IACS |
Extra spring hard | Maximum cold-rolled strength; for flat springs with essentially no forming after rolling. | 505 | 560 | 2 | 175 HB | 38 % IACS |
What is C40500-OS035?
C40500-OS035 is C40500 in the OS035 temper — softest commercial strip temper — pick for deep drawing, severe coining and heavy forming. C40500-OS035 has a yield strength of 105 MPa (15.2 ksi) and a tensile strength of 275 MPa (39.9 ksi) — weaker than 85% of copper alloy grades. Elongation at break is 45% and the elastic modulus is 115 GPa (16.7 Msi). C40500-OS035 has a density of 8.86 g/cm³ (0.32 lb/in³), heavier than 68% of copper alloy grades. It melts at 1,035°C (1,895 °F). H02 is the default condition FabDigit quotes; OS035 is available on request or by drawing note.
Advantages
- Forms and bends easily — 95/100, better than 94% of copper alloy grades
- Ductile — tolerates forming and impact — 45%, better than 91% of copper alloy grades
- High electrical conductivity — 41 % IACS, better than 75% of copper alloy grades
Limitations
- Difficult to machine — 18/100, worse than 100% of copper alloy grades
- Low strength — 105 MPa (15.2 ksi), worse than 85% of copper alloy grades
C40500-OS035 properties
Typical room-temperature values for C40500-OS035; 16 are specific to this condition. Other listed values are C40500 reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
C40500-OS035 has a density of 8.86 g/cm³ (0.32 lb/in³), heavier than 68% of copper alloy grades. It melts at 1,035°C (1,895 °F).
Mechanical12
C40500-OS035 has a yield strength of 105 MPa (15.2 ksi) and a tensile strength of 275 MPa (39.9 ksi) — weaker than 85% of copper alloy grades. Elongation at break is 45% and the elastic modulus is 115 GPa (16.7 Msi).
Thermal6
C40500-OS035 is rated for continuous service to 250°C (482 °F). It conducts heat at 172 W/m·K (99.4 BTU/hr·ft·°F), better than 74% of copper alloy grades. Thermal expansion is 18.4 µm/m·K (10.2 µin/in·°F).
Electrical3
C40500-OS035 conducts electricity at 41 % IACS, better than 75% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is very good (70/100), better than 76% of copper alloy grades.
Sustainability4
Producing a kilogram of C40500-OS035 takes about 57 MJ of energy and emits 3.6 kg of CO₂ — less than 52% of copper alloy grades. Typical recycled content is 40%.
Manufacturability8
C40500-OS035's machinability is poor (18/100, worse than 100% of copper alloy grades); weldability fair (40/100); formability excellent (95/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with C40500-OS035
Is C40500 easy to machine?
Unleaded tin brass machines gummy with long chips — rating ~20 % of free-cutting brass; use sharp positive-rake tools, high speed and flood coolant, or switch to C36000 if turning-intensive.
Can C40500 be welded?
Solders and brazes readily and resistance-welds well; arc/gas fusion welding is only fair because of zinc fuming and porosity.
Can C40500 be formed, bent or molded?
Excellent cold formability in OS tempers (deep draw, coin, roll-form); interanneal near 450–600 °C and stress-relieve cold-worked parts around 200 °C to avoid ammonia stress-corrosion cracking.
What surface finishes work on C40500?
Not anodizable — buff or barrel-polish to a bright bronze finish, then lacquer, patinate, or electroplate with Ni/Sn/Ag over a suitable strike.
C40500 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 |
|---|---|---|
| Cuincludes Ag | 94 – 96 | 95 |
| Sn | 0.7 – 1.3 | 1 |
| Pb | ≤ 0.05 | — |
| Fe | ≤ 0.05 | — |
| Zn | balance | — |
C40500-OS035 — frequently asked
What is C40500-OS035 used for?
C40500-OS035 is typically used for coinage blanks, electrical contacts and small stampings. In short: coinage-grade tin brass; excellent coining and drawing; machining rating only 22.
What is the yield strength of C40500-OS035?
C40500-OS035 has a typical yield strength of 105 MPa (15.2 ksi) and a tensile strength of 275 MPa (39.9 ksi) — weaker than 85% of copper alloy grades. Strength varies by condition: see the 9 listed tempers.
Is C40500-OS035 easy to machine?
Not especially — machinability is rated poor (18/100, worse than 100% of copper alloy grades). Unleaded tin brass machines gummy with long chips — rating ~20 % of free-cutting brass; use sharp positive-rake tools, high speed and flood coolant, or switch to C36000 if turning-intensive.
Can C40500-OS035 be welded?
With care — weldability is rated fair (40/100). Solders and brazes readily and resistance-welds well; arc/gas fusion welding is only fair because of zinc fuming and porosity.
What surface finishes work on C40500-OS035?
Not anodizable — buff or barrel-polish to a bright bronze finish, then lacquer, patinate, or electroplate with Ni/Sn/Ag over a suitable strike.
Can C40500-OS035 be formed, bent or molded?
Excellent cold formability in OS tempers (deep draw, coin, roll-form); interanneal near 450–600 °C and stress-relieve cold-worked parts around 200 °C to avoid ammonia stress-corrosion cracking.
What is the maximum service temperature of C40500-OS035?
C40500-OS035 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 C40500-H02 and C40500-OS035?
H02 is the default condition — the general-purpose stocked strip temper — balanced strength and bendability for stampings and contacts. OS035: softest commercial strip temper — pick for deep drawing, severe coining and heavy forming. Yield strength is 330 MPa in H02 versus 105 MPa in OS035.
Sources
- ASTM B36/B36M — Brass Plate, Sheet, Strip and Rolled Bar — ASTM International (2018)
- CDA/copper.org Alloy Database — C40500 — Copper Development Association (2024)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- ASM Handbook Vol. 13B — Corrosion: Materials — ASM International (2005)
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.