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Copper Alloy C19020-HR02

Temper

UNS C19020

HR02 = half hard, cold rolled and stress relieved

Choose when tight-radius bending (small R/t) is required together with good stress-relaxation resistance.

High cost $$$$

Values for the HR02 condition

Other C19020 tempers and conditions

C19020 is listed in 7 conditions; see the grade overview at C19020.

Compare all 7 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
Soft annealed
Pick for deep-drawn or severely formed parts that will be work-hardened or heat treated afterwards.1403203252 HRB42 % IACS
Half hard
Cold-rolled half-hard strip when maximum bendability matters more than relaxation resistance.38042512123 HB41 % IACS
HR02This page
Half hard, cold rolled and stress relieved
Choose when tight-radius bending (small R/t) is required together with good stress-relaxation resistance.41045013131 HB46 % IACS
Full hard
Cold-rolled hard strip for stamped parts that receive their own downstream thermal treatment.4655006145 HB41 % IACS
HR04Default
Full hard, cold rolled and stress relieved
The workhorse connector temper: best balance of ~520 MPa strength, formability and low stress relaxation.4905206152 HB45 % IACS
Extra hard, cold rolled and stress relieved
Higher contact force in thin gauges where only generous bend radii (or bend-good-way stamping) are used.5455704166 HB45 % IACS
Spring temper, cold rolled and stress relieved
Maximum yield strength and spring-back for high-force contact springs; least formable temper.5906103180 HB44 % IACS

What is C19020-HR02?

C19020-HR02 is C19020 in the HR02 temper — choose when tight-radius bending (small R/t) is required together with good stress-relaxation resistance. C19020-HR02 has a yield strength of 410 MPa (59.5 ksi) and a tensile strength of 450 MPa (65.3 ksi) — stronger than 81% of copper alloy grades. Elongation at break is 13% and the elastic modulus is 125 GPa (18.1 Msi). C19020-HR02 has a density of 8.9 g/cm³ (0.322 lb/in³), heavier than 77% of copper alloy grades. It melts at 1,065°C (1,949 °F). HR04 is the default condition FabDigit quotes; HR02 is available on request or by drawing note.

Advantages

  • Forms and bends easily — 72/100, better than 82% of copper alloy grades
  • High strength — 410 MPa (59.5 ksi), better than 81% of copper alloy grades
  • High electrical conductivity — 46 % IACS, better than 78% of copper alloy grades
  • Conducts heat well — 185 W/m·K (106.9 BTU/hr·ft·°F), better than 76% of copper alloy grades

Limitations

  • Limited service temperature — 175°C (347 °F), worse than 92% of copper alloy grades

C19020-HR02 properties

Typical room-temperature values for C19020-HR02; 15 are specific to this condition. Other listed values are C19020 reference data and may not represent this condition. Bars are the position among copper alloy grades.

Physical3

C19020-HR02 has a density of 8.9 g/cm³ (0.322 lb/in³), heavier than 77% of copper alloy grades. It melts at 1,065°C (1,949 °F).

Density8.9 g/cm³0.32 lb/in³
Melting Point (Solidus)1,065°C1,949 °F
Liquidus Temperature1,085°C1,985 °F

Mechanical12

C19020-HR02 has a yield strength of 410 MPa (59.5 ksi) and a tensile strength of 450 MPa (65.3 ksi) — stronger than 81% of copper alloy grades. Elongation at break is 13% and the elastic modulus is 125 GPa (18.1 Msi).

Elastic (Young's) Modulus125 GPa18.1 Msi
Shear Modulus47 GPa6.8 Msi
Bulk Modulus138 GPa20 Msi
Poisson's Ratio0.33
Tensile Strength (Ultimate)450 MPa65.3 ksi
Yield Strength (0.2% offset)410 MPa59.5 ksi
Elongation at Break13%
Shear Strength290 MPa42.1 ksi
Fatigue Strength (Endurance Limit)205 MPa29.7 ksi
Hardness, Brinell131 HB
Hardness, Rockwell B75 HRB
Hardness, Vickers138 HV

Thermal6

C19020-HR02 is rated for continuous service to 175°C (347 °F). It conducts heat at 185 W/m·K (106.9 BTU/hr·ft·°F), better than 76% of copper alloy grades. Thermal expansion is 17.6 µm/m·K (9.78 µin/in·°F).

Thermal Conductivity185 W/m·K107 BTU/hr·ft·°F
Specific Heat Capacity385 J/kg·K0.09 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)17.6 µm/m·K9.8 µin/in·°F
Latent Heat of Fusion205 J/g88.1 BTU/lb
Max Service Temperature (continuous)175°C347 °F
Min Service Temperature-196°C-321 °F

Electrical3

C19020-HR02 conducts electricity at 46 % IACS, better than 78% of copper alloy grades.

Electrical Conductivity46 % IACS
Electrical Resistivity3.75×10⁻⁸ Ω·m1.48 µΩ·in
Magnetic Responsenon-magnetic

Chemical & Environmental3

Corrosion resistance is good (62/100), worse than 57% of copper alloy grades.

Galvanic Potential (seawater, vs SCE)-0.2 V
Corrosion ResistanceGood62/100
Chemical Resistance SummaryGood in fresh/marine atmospheres, fresh water and neutral salts; attacked by ammonia/amines, oxidizing acids, sulfides and mercury compounds; tarnishes in sulfur-bearing air so plating is usual for contacts.

Sustainability4

Producing a kilogram of C19020-HR02 takes about 57 MJ of energy and emits 3.8 kg of CO₂ — less than 52% of copper alloy grades. Typical recycled content is 35%.

Embodied Energy (primary production)57 MJ/kg24,506 BTU/lb
Embodied Carbon (primary production)3.8 kg CO₂/kg
Embodied Water300 L/kg35.9 gal/lb
Typical Recycled Content35%

Manufacturability7

C19020-HR02's machinability is poor (27/100, worse than 81% of copper alloy grades); weldability fair (45/100); formability very good (72/100).

MachinabilityPoor27/100
Machinability Rating (AISI 1212 = 100 %)20%
WeldabilityFair45/100
Formability (cold)Very good72/100
Brazeability / SolderabilityExcellent90/100
PolishabilityVery good75/100
Anodizing Responsen/a — copper alloy; use tin, silver, nickel or gold plating instead of anodizing

Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.

Working with C19020-HR02

Is C19020 easy to machine?

Gummy like most low-alloy coppers — use sharp positive-rake carbide, high speed, generous coolant; chip breaking is poor, rate roughly 20 % of free-cutting brass.

Can C19020 be welded?

Resistance and laser welding of thin strip are routine; fusion welding softens the cold-worked temper locally and lowers spring force, so joints are usually crimped, welded at tabs, or soldered.

Can C19020 be formed, bent or molded?

Excellent progressive-die stamping and coining; bend R/t improves markedly in the stress-relieved HR tempers, but bad-way bends in HR06/HR08 need generous radii.

What surface finishes work on C19020?

Not anodizable — standard finishes are electrolytic tin, tin-lead-free reflow, nickel underlay with gold or palladium-nickel flash for contact areas.

C19020 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.

ElementSpec limit (wt %)Nominal
Nisolid-solution + phosphide strengthening0.8 – 1.81
Snsolid-solution strengthening, relaxation resistance0.5 – 1.50.9
Pforms Ni-P precipitates, deoxidizer0.01 – 0.10.05
Cu97.0 % min Cu + named elementsbalance—

C19020-HR02 — frequently asked

What is C19020-HR02 used for?

C19020-HR02 is typically used for electronic connectors, terminals and lead frames. In short: connector-grade spring copper; good stress-relaxation resistance; 45 % IACS at 520 MPa.

What is the yield strength of C19020-HR02?

C19020-HR02 has a typical yield strength of 410 MPa (59.5 ksi) and a tensile strength of 450 MPa (65.3 ksi) — stronger than 81% of copper alloy grades. Strength varies by condition: see the 7 listed tempers.

Is C19020-HR02 easy to machine?

Not especially — machinability is rated poor (27/100, worse than 81% of copper alloy grades). Gummy like most low-alloy coppers — use sharp positive-rake carbide, high speed, generous coolant; chip breaking is poor, rate roughly 20 % of free-cutting brass.

Can C19020-HR02 be welded?

With care — weldability is rated fair (45/100). Resistance and laser welding of thin strip are routine; fusion welding softens the cold-worked temper locally and lowers spring force, so joints are usually crimped, welded at tabs, or soldered.

What surface finishes work on C19020-HR02?

Not anodizable — standard finishes are electrolytic tin, tin-lead-free reflow, nickel underlay with gold or palladium-nickel flash for contact areas.

Can C19020-HR02 be formed, bent or molded?

Excellent progressive-die stamping and coining; bend R/t improves markedly in the stress-relieved HR tempers, but bad-way bends in HR06/HR08 need generous radii.

What is the maximum service temperature of C19020-HR02?

C19020-HR02 is rated for continuous use to about 175°C (347 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

What is the difference between C19020-HR04 and C19020-O60?

HR04 is the default condition — the workhorse connector temper: best balance of ~520 MPa strength, formability and low stress relaxation. O60: pick for deep-drawn or severely formed parts that will be work-hardened or heat treated afterwards. Yield strength is 490 MPa in HR04 versus 140 MPa in O60.

Sources

  1. ASTM B888 / B465-class copper alloy strip for electrical connectors — ASTM International (2020)
  2. CDA/UNS Standard Designations for Wrought Copper Alloys (C19020) — Copper Development Association (2023)
  3. ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
  4. Cu-Ni-Sn-P high-performance connector strip datasheet — Wieland / Kobe Steel (comparable grades) (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.