Copper Alloy C43400
UNS C43400
C43400 is a wrought tin brass with moderate strength and good corrosion resistance, supplied as strip and formed sections in tempers from OS035 to H10.
Reference datasheet — C43400 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the H02 condition
C43400 tempers and conditions
C43400 is supplied in 9 conditions, soft to hard. H02 is the default FabDigit quotes; the values on this page are for it.
Compare all 9 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed to 0.035 mm grain size | Softest commercial strip temper — pick for deep drawing, tight bends and hose convolution forming. | 124 | 345 | 48 | 50 HRB | 27 % IACS |
Annealed to 0.015 mm grain size | Fine-grain anneal — choose when a smooth orange-peel-free surface after forming matters more than maximum ductility. | 140 | 359 | 45 | 55 HRB | 27 % IACS |
Quarter hard | Light cold work — a compromise temper for parts that are formed then need modest stiffness. | 310 | 400 | 25 | 70 HRB | 26 % IACS |
H02Default Half hard | The default stocked strip temper — balanced strength and bendability for weatherstrip, hose strip and formed hardware. | 380 | 448 | 14 | 78 HRB | 26 % IACS |
Three-quarter hard | Higher spring-back and strength for lightly formed clips and retainers. | 427 | 496 | 9 | 83 HRB | 26 % IACS |
Full hard | Standard hard strip for flexible hose interlock and weatherstrip that is only slightly bent after slitting. | 475 | 545 | 5 | 87 HRB | 26 % IACS |
Extra hard | For flat springs and contacts where only very generous bend radii are used. | 525 | 600 | 4 | 90 HRB | 25 % IACS |
Spring hard | Spring temper strip for resilient sealing fingers and contact springs; forming limited to large radii, stress-relieve after forming. | 565 | 634 | 3 | 92 HRB | 25 % IACS |
Extra spring hard | Maximum strength/spring rate available in this alloy; essentially flat-form use only. | 586 | 655 | 2 | 93 HRB | 25 % IACS |
What is C43400?
C43400 is a wrought tin brass with moderate strength and good corrosion resistance, supplied as strip and formed sections in tempers from OS035 to H10. It is used for convoluted flexible hose, weatherstripping and formed hardware because of its high cold formability (score 70): the default condition gives 380 MPa yield, 448 MPa tensile, 14% elongation, 78 HRB and 26% IACS. Maximum service temperature is 150 °C, fusion welding is only fair because of zinc fume, and hard tempers need stress relief against season cracking. C43000 is the nearest alternative when higher elongation is required. C43400 has a density of 8.75 g/cm³ (0.316 lb/in³), lighter than 51% of copper alloy grades. It melts at 1,000°C (1,832 °F). C43400 has a yield strength of 380 MPa (55.1 ksi) and a tensile strength of 448 MPa (65 ksi) — stronger than 77% of copper alloy grades. Elongation at break is 14% and the elastic modulus is 110 GPa (16 Msi).
What is C43400 used for?
- flexible hose
- weatherstripping
- hardware components
Advantages
- Forms and bends easily — 70/100, better than 80% of copper alloy grades
- High strength — 380 MPa (55.1 ksi), better than 77% of copper alloy grades
Limitations
- Limited service temperature — 150°C (302 °F), worse than 96% of copper alloy grades
C43400 properties
Typical room-temperature values for C43400-H02; bars are the position among copper alloy grades.
Physical3
C43400 has a density of 8.75 g/cm³ (0.316 lb/in³), lighter than 51% of copper alloy grades. It melts at 1,000°C (1,832 °F).
Mechanical11
C43400 has a yield strength of 380 MPa (55.1 ksi) and a tensile strength of 448 MPa (65 ksi) — stronger than 77% of copper alloy grades. Elongation at break is 14% and the elastic modulus is 110 GPa (16 Msi).
Thermal6
C43400 is rated for continuous service to 150°C (302 °F). It conducts heat at 121 W/m·K (69.9 BTU/hr·ft·°F), better than 68% of copper alloy grades. Thermal expansion is 19.8 µm/m·K (11 µin/in·°F).
Electrical3
C43400 conducts electricity at 26 % IACS, better than 63% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (62/100), worse than 57% of copper alloy grades.
Sustainability4
Producing a kilogram of C43400 takes about 62 MJ of energy and emits 4 kg of CO₂ — more than 76% of copper alloy grades. Typical recycled content is 45%.
Manufacturability7
C43400's machinability is poor (32/100, worse than 57% of copper alloy grades); weldability good (55/100); formability very good (70/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the copper alloy family
Yield strength against density for every copper alloy grade FabDigit runs. C43400 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with C43400
Is C43400 easy to machine?
Machinability ≈30 % of C36000 — gummy, long chips; use sharp positive-rake tools, high speed and good lubrication; not a screw-machine alloy.
Can C43400 be welded?
Excellent soldering and brazing; resistance and gas-shielded arc welding are fair — zinc fume and porosity are the main issues, so mechanical joints or brazing are preferred.
Can C43400 be formed, bent or molded?
Excellent cold formability in OS tempers (deep draw, roll form, convolute); in H04 and above restrict bends to generous radii transverse to rolling direction.
C43400 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 |
|---|---|---|
| CuCu + named elements ≥ 99.6 % | 84 – 87 | 85.5 |
| Snimproves dezincification resistance | 0.4 – 1 | 0.7 |
| Pbimpurity max | ≤ 0.05 | |
| Feimpurity max | ≤ 0.05 | |
| Znremainder, ≈13–15 % | balance |
What surface finishes work on C43400?
Bright-dips, buffs and plates (Ni, Sn, Cr) readily; not anodizable — protect with lacquer or clear coat to prevent tarnish, and stress-relieve hard tempers (≈200–260 °C) to avoid season cracking.
Surface treatments FabDigit runs on copper alloy parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
How much does C43400 cost?
C43400 is a high-cost copper alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
C43400 — frequently asked
What is C43400 used for?
C43400 is typically used for flexible hose, weatherstripping and hardware components. In short: formable tin-brass strip; flexible hose and weatherstrip grade; 150 °C service limit.
What is the yield strength of C43400?
C43400 has a typical yield strength of 380 MPa (55.1 ksi) and a tensile strength of 448 MPa (65 ksi) — stronger than 77% of copper alloy grades. Strength varies by condition: see the 9 listed tempers.
Is C43400 easy to machine?
Not especially — machinability is rated poor (32/100, worse than 57% of copper alloy grades). Machinability ≈30 % of C36000 — gummy, long chips; use sharp positive-rake tools, high speed and good lubrication; not a screw-machine alloy.
Can C43400 be welded?
Yes — weldability is rated good (55/100). Excellent soldering and brazing; resistance and gas-shielded arc welding are fair — zinc fume and porosity are the main issues, so mechanical joints or brazing are preferred.
What surface finishes work on C43400?
Bright-dips, buffs and plates (Ni, Sn, Cr) readily; not anodizable — protect with lacquer or clear coat to prevent tarnish, and stress-relieve hard tempers (≈200–260 °C) to avoid season cracking.
Can C43400 be formed, bent or molded?
Excellent cold formability in OS tempers (deep draw, roll form, convolute); in H04 and above restrict bends to generous radii transverse to rolling direction.
What is the maximum service temperature of C43400?
C43400 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 C43400-H02 and C43400-OS035?
H02 is the default condition — the default stocked strip temper — balanced strength and bendability for weatherstrip, hose strip and formed hardware. OS035: softest commercial strip temper — pick for deep drawing, tight bends and hose convolution forming. Yield strength is 380 MPa in H02 versus 124 MPa in OS035.
How much does C43400 cost?
C43400 is a high-cost copper alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- CDA Alloy Datasheet C43400 (tin brass) — Copper Development Association (2023)
- ASTM B591 — Copper-Zinc-Tin Alloy Plate, Sheet, Strip and Rolled Bar — ASTM International (2022)
- ASTM B601 — Temper Designations for Copper and Copper Alloys — ASTM International (2019)
- 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; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.