Copper Alloy C23400-H04
Supply condition
UNS C23400
H04 = full hard
Standard hard temper for flat stampings, washers and blanked hardware needing stiffness and edge quality.
Values for the H04 condition
Other C23400 tempers and conditions
C23400 is listed in 8 conditions; see the grade overview at C23400.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Pick for deep drawing, spinning and severe forming where maximum ductility is needed. | 95 | 290 | 48 | 58 HB | — |
Quarter hard | Light temper for parts that still need moderate bending/forming after a modest strength gain. | 235 | 310 | 28 | 85 HB | — |
H02Default Half hard | The general-purpose stocked temper: good strength with enough ductility for 90° bends and light forming. | 285 | 355 | 14 | 105 HB | — |
Three-quarter hard | Use when H02 strength is marginal but some bending across the grain is still required. | 325 | 390 | 10 | 118 HB | — |
H04This page Full hard | Standard hard temper for flat stampings, washers and blanked hardware needing stiffness and edge quality. | 370 | 430 | 6 | 132 HB | — |
Extra hard | Choose for flat springs and clips where forming is limited to gentle radii along the grain. | 425 | 485 | 4 | 145 HB | — |
Spring hard | Spring temper for contacts, retainers and shims requiring high elastic limit; forming must be minimal. | 465 | 525 | 3 | 155 HB | — |
Extra spring hard | Maximum cold-worked strength; only for flat blanked spring parts with essentially no forming. | 500 | 565 | 3 | 165 HB | — |
What is C23400-H04?
C23400-H04 is C23400 supplied in the H04 condition — standard hard temper for flat stampings, washers and blanked hardware needing stiffness and edge quality. C23400-H04 has a yield strength of 370 MPa (53.7 ksi) and a tensile strength of 430 MPa (62.4 ksi) — stronger than 75% of copper alloy grades. Elongation at break is 6% and the elastic modulus is 112 GPa (16.2 Msi). C23400-H04 has a density of 8.72 g/cm³ (0.315 lb/in³), lighter than 54% of copper alloy grades. It melts at 990°C (1,814 °F). H02 is the default condition FabDigit quotes; H04 is available on request or by drawing note.
Advantages
- Polishes to a fine finish — 85/100, better than 92% of copper alloy grades
- High strength — 370 MPa (53.7 ksi), better than 75% of copper alloy grades
Limitations
- Limited service temperature — 150°C (302 °F), worse than 96% of copper alloy grades
- Limited ductility — 6%, worse than 89% of copper alloy grades
C23400-H04 properties
Typical room-temperature values for C23400-H04; 14 are specific to this condition. Other listed values are C23400 reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
C23400-H04 has a density of 8.72 g/cm³ (0.315 lb/in³), lighter than 54% of copper alloy grades. It melts at 990°C (1,814 °F).
Mechanical13
C23400-H04 has a yield strength of 370 MPa (53.7 ksi) and a tensile strength of 430 MPa (62.4 ksi) — stronger than 75% of copper alloy grades. Elongation at break is 6% and the elastic modulus is 112 GPa (16.2 Msi).
Thermal6
C23400-H04 is rated for continuous service to 150°C (302 °F). It conducts heat at 150 W/m·K (86.7 BTU/hr·ft·°F), better than 72% of copper alloy grades. Thermal expansion is 19.1 µm/m·K (10.6 µin/in·°F).
Electrical3
C23400-H04 conducts electricity at 34 % IACS, better than 72% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is fair (54/100), worse than 91% of copper alloy grades.
Sustainability4
Producing a kilogram of C23400-H04 takes about 57 MJ of energy and emits 3.5 kg of CO₂ — less than 52% of copper alloy grades. Typical recycled content is 40%.
Manufacturability7
C23400-H04's machinability is fair (35/100, better than 51% of copper alloy grades); weldability fair (45/100); formability poor (32/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with C23400-H04
Is C23400 easy to machine?
Gummy, long-chipping alloy (~30% of AISI 1212) — use sharp positive-rake tools, high speed, light feed and flood coolant; not a substitute for C36000 in screw-machine work.
Can C23400 be welded?
Solders and brazes superbly; resistance and oxyacetylene welding are usable, but gas-shielded arc welding is only fair due to zinc fume and porosity.
Can C23400 be formed, bent or molded?
Excellent deep-drawing and spinning in O61/H01; interstage anneal at 425–650 °C, and stress-relieve cold-worked parts at 250–300 °C to prevent ammonia season cracking.
What surface finishes work on C23400?
Buffs to a bright red-gold; commonly clear-lacquered, benzotriazole-passivated, chemically antiqued, or nickel/chrome/gold plated. Anodizing does not apply.
C23400 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 |
|---|---|---|
| CuAg may be counted as Cu | 81 – 84 | 82.5 |
| Pbimpurity limit | ≤ 0.05 | — |
| Feimpurity limit | ≤ 0.05 | — |
| Znremainder, nominally ~17.5% | balance | — |
C23400-H04 — frequently asked
What is C23400-H04 used for?
C23400-H04 is typically used for hardware, plumbing fittings, decorative trim and stamped components. In short: red-gold hardware brass; formable, not free-cutting; direct C23000 substitute.
What is the yield strength of C23400-H04?
C23400-H04 has a typical yield strength of 370 MPa (53.7 ksi) and a tensile strength of 430 MPa (62.4 ksi) — stronger than 75% of copper alloy grades. Strength varies by condition: see the 8 listed tempers.
Is C23400-H04 easy to machine?
Not especially — machinability is rated fair (35/100, better than 51% of copper alloy grades). Gummy, long-chipping alloy (~30% of AISI 1212) — use sharp positive-rake tools, high speed, light feed and flood coolant; not a substitute for C36000 in screw-machine work.
Can C23400-H04 be welded?
With care — weldability is rated fair (45/100). Solders and brazes superbly; resistance and oxyacetylene welding are usable, but gas-shielded arc welding is only fair due to zinc fume and porosity.
What surface finishes work on C23400-H04?
Buffs to a bright red-gold; commonly clear-lacquered, benzotriazole-passivated, chemically antiqued, or nickel/chrome/gold plated. Anodizing does not apply.
Can C23400-H04 be formed, bent or molded?
Excellent deep-drawing and spinning in O61/H01; interstage anneal at 425–650 °C, and stress-relieve cold-worked parts at 250–300 °C to prevent ammonia season cracking.
What is the maximum service temperature of C23400-H04?
C23400-H04 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 C23400-H02 and C23400-H10?
H02 is the default condition — the general-purpose stocked temper: good strength with enough ductility for 90° bends and light forming. H10: maximum cold-worked strength; only for flat blanked spring parts with essentially no forming. Yield strength is 285 MPa in H02 versus 500 MPa in H10.
Sources
- ASTM B36/B36M — Brass Plate, Sheet, Strip and Rolled Bar — ASTM International (2018)
- ASTM B587 — Welded Brass Tube — ASTM International (2020)
- Copper Alloy Data (UNS C23400 / red brass family) — 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.