Copper Alloy C19500-H04
Supply condition
UNS C19500
H04 = full hard
High-strength strip for flat springs and contacts formed with generous bend radii.
Values for the H04 condition
Other C19500 tempers and conditions
C19500 is listed in 7 conditions; see the grade overview at C19500.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Soft annealed | Maximum formability for deep drawing or severe bending before hardening/aging. | 170 | 400 | 24 | 55 HRB | 45 % IACS |
Quarter hard | Light cold work when tight forming is still needed but annealed strength is too low. | 440 | 483 | 9 | 74 HRB | 50 % IACS |
Solution heat treated and precipitation hardened | Choose when both good formability and high conductivity with stable strength after forming are required — aging restores conductivity and stress-relaxation resistance. | 470 | 540 | 10 | 78 HRB | 55 % IACS |
H02Default Half hard | Standard stocked strip temper: balanced strength, bendability and 50% IACS for terminals and lead frames. | 517 | 552 | 5 | 80 HRB | 50 % IACS |
Three-quarter hard | Higher strength for stamped contacts with only gentle bends. | 552 | 586 | 4 | 84 HRB | 50 % IACS |
H04This page Full hard | High-strength strip for flat springs and contacts formed with generous bend radii. | 586 | 621 | 3 | 88 HRB | 50 % IACS |
Spring hard | Maximum as-rolled strength for spring contacts; bends must be along favourable grain direction. | 640 | 670 | 2 | 92 HRB | 50 % IACS |
What is C19500-H04?
C19500-H04 is C19500 supplied in the H04 condition — high-strength strip for flat springs and contacts formed with generous bend radii. C19500-H04 has a yield strength of 586 MPa (85 ksi) and a tensile strength of 621 MPa (90.1 ksi) — stronger than 94% of copper alloy grades. Elongation at break is 3% and the elastic modulus is 131 GPa (19 Msi). C19500-H04 has a density of 8.78 g/cm³ (0.317 lb/in³), heavier than 53% of copper alloy grades. It melts at 1,030°C (1,886 °F). H02 is the default condition FabDigit quotes; H04 is available on request or by drawing note.
Advantages
- High strength — 586 MPa (85 ksi), better than 94% of copper alloy grades
- Stiff — 131 GPa (19 Msi), better than 91% of copper alloy grades
- High electrical conductivity — 50 % IACS, better than 79% of copper alloy grades
- Conducts heat well — 200 W/m·K (115.6 BTU/hr·ft·°F), better than 78% of copper alloy grades
Limitations
- Limited ductility — 3%, worse than 97% of copper alloy grades
C19500-H04 properties
Typical room-temperature values for C19500-H04; 11 are specific to this condition. Other listed values are C19500 reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
C19500-H04 has a density of 8.78 g/cm³ (0.317 lb/in³), heavier than 53% of copper alloy grades. It melts at 1,030°C (1,886 °F).
Mechanical11
C19500-H04 has a yield strength of 586 MPa (85 ksi) and a tensile strength of 621 MPa (90.1 ksi) — stronger than 94% of copper alloy grades. Elongation at break is 3% and the elastic modulus is 131 GPa (19 Msi).
Thermal6
C19500-H04 is rated for continuous service to 180°C (356 °F). It conducts heat at 200 W/m·K (115.6 BTU/hr·ft·°F), better than 78% of copper alloy grades. Thermal expansion is 17 µm/m·K (9.44 µin/in·°F).
Electrical3
C19500-H04 conducts electricity at 50 % IACS, better than 79% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (62/100), worse than 57% of copper alloy grades.
Sustainability4
Producing a kilogram of C19500-H04 takes about 53 MJ of energy and emits 3.6 kg of CO₂ — less than 85% of copper alloy grades. Typical recycled content is 40%.
Manufacturability7
C19500-H04's machinability is poor (34/100, worse than 53% of copper alloy grades); weldability fair (40/100); formability fair (35/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with C19500-H04
Is C19500 easy to machine?
Gummy like most high-conductivity coppers (≈20 % of free-cutting brass) — use sharp positive-rake tools, high speed, generous coolant; stamping and blanking are the normal routes.
Can C19500 be welded?
Resistance and laser welding are practical; fusion welding is poor due to high conductivity and risk of overaging/softening in the HAZ.
Can C19500 be formed, bent or molded?
Excellent progressive-die stamping in O60–H02; in H04/H08 keep bend radii ≥1–2t and bend transverse to rolling direction; stress-relieve/age after forming to restore relaxation resistance.
What surface finishes work on C19500?
Solders and brazes readily; commonly tin-, nickel-, silver- or gold-plated for contacts; not anodizable — passivate or plate to prevent tarnish.
C19500 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 |
|---|---|---|
| Fe | 1 – 2 | 1.5 |
| Co | 0.3 – 1.3 | 0.8 |
| Sn | 0.1 – 1 | 0.6 |
| P | 0.01 – 0.35 | 0.05 |
| Zn | ≤ 0.2 | — |
| Pb | ≤ 0.02 | — |
| Curemainder, ≈96 % min including Ag | balance | — |
C19500-H04 — frequently asked
What is C19500-H04 used for?
C19500-H04 is typically used for electrical connectors, switch and relay parts and wear-resistant electrical contacts. In short: age-hardenable contact alloy; 517 MPa yield at 50 % IACS; highest wear resistance in family.
What is the yield strength of C19500-H04?
C19500-H04 has a typical yield strength of 586 MPa (85 ksi) and a tensile strength of 621 MPa (90.1 ksi) — stronger than 94% of copper alloy grades. Strength varies by condition: see the 7 listed tempers.
Is C19500-H04 easy to machine?
Not especially — machinability is rated poor (34/100, worse than 53% of copper alloy grades). Gummy like most high-conductivity coppers (≈20 % of free-cutting brass) — use sharp positive-rake tools, high speed, generous coolant; stamping and blanking are the normal routes.
Can C19500-H04 be welded?
With care — weldability is rated fair (40/100). Resistance and laser welding are practical; fusion welding is poor due to high conductivity and risk of overaging/softening in the HAZ.
What surface finishes work on C19500-H04?
Solders and brazes readily; commonly tin-, nickel-, silver- or gold-plated for contacts; not anodizable — passivate or plate to prevent tarnish.
Can C19500-H04 be formed, bent or molded?
Excellent progressive-die stamping in O60–H02; in H04/H08 keep bend radii ≥1–2t and bend transverse to rolling direction; stress-relieve/age after forming to restore relaxation resistance.
What is the maximum service temperature of C19500-H04?
C19500-H04 is rated for continuous use to about 180°C (356 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between C19500-H02 and C19500-O60?
H02 is the default condition — standard stocked strip temper: balanced strength, bendability and 50% IACS for terminals and lead frames. O60: maximum formability for deep drawing or severe bending before hardening/aging. Yield strength is 517 MPa in H02 versus 170 MPa in O60.
Sources
- ASTM B465 / B888 (Cu-Fe alloy strip and lead-frame strip) — ASTM International (2019)
- CDA Alloy Database — C19500 property sheet — Copper Development Association (2023)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- High-performance copper strip for connectors and lead frames — Copper strip producers (Wieland / Olin-Brass class data) (2022)
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.