Copper Alloy C71500-H55
Temper
UNS C71500 · ASTM B111/B466 · EN CuNi30Mn1Fe, CW354H
H55 = light drawn
Standard condenser/heat-exchanger tube temper: higher strength than annealed while still expandable into tubesheets.
Values for the H55 condition
Other C71500 tempers and conditions
C71500 is listed in 9 conditions; see the grade overview at C71500.
Compare all 9 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
O61Default Annealed | Default stock condition for tube, plate and sheet — maximum ductility for bending, expanding and welding. | 140 | 380 | 45 | 80 HB | — |
AM heat treated | Post-processed AM condition: homogenised, low residual stress, ductility and seawater corrosion behaviour close to wrought annealed. | 165 | 400 | 40 | 85 HB | 4.5 % IACS |
AM as-built | Printed CuNi30 parts with fine cellular structure — strength between annealed and half-hard wrought, with residual stress. | 260 | 450 | 30 | 110 HB | 4.1 % IACS |
H55This page Light drawn | Standard condenser/heat-exchanger tube temper: higher strength than annealed while still expandable into tubesheets. | 275 | 415 | 30 | 105 HB | 4.6 % IACS |
Quarter hard | Mild cold work for parts needing extra stiffness but still moderate bending capability. | 275 | 415 | 25 | 110 HB | 4.6 % IACS |
Drawn and stress relieved | Drawn tube with a low-temperature stress relief — for service where residual stress and distortion must be minimised. | 345 | 450 | 20 | 125 HB | 4.6 % IACS |
Half hard | Good strength/formability compromise for flanges, brackets and machined marine fittings. | 380 | 450 | 15 | 130 HB | 4.6 % IACS |
Full hard | High-strength strip/rod for springs, fasteners and wear surfaces where forming is minimal. | 480 | 515 | 8 | 150 HB | 4.5 % IACS |
Hard drawn | Maximum as-drawn strength for shafting, wire and high-pressure small-bore tube. | 545 | 585 | 4 | 175 HB | 4.5 % IACS |
What is C71500-H55?
C71500-H55 is C71500 in the H55 temper — standard condenser/heat-exchanger tube temper: higher strength than annealed while still expandable into tubesheets. C71500-H55 has a yield strength of 275 MPa (39.9 ksi) and a tensile strength of 415 MPa (60.2 ksi) — stronger than 57% of copper alloy grades. Elongation at break is 30% and the elastic modulus is 152 GPa (22 Msi). C71500-H55 has a density of 8.94 g/cm³ (0.323 lb/in³), heavier than 90% of copper alloy grades. It melts at 1,171°C (2,140 °F). O61 is the default condition FabDigit quotes; H55 is available on request or by drawing note.
Advantages
- Stiff — 152 GPa (22 Msi), better than 99% of copper alloy grades
- Good corrosion resistance — 82/100, better than 98% of copper alloy grades
- High service temperature — 350°C (662 °F), better than 95% of copper alloy grades
- Readily welded — 82/100, better than 95% of copper alloy grades
- Forms and bends easily — 70/100, better than 80% of copper alloy grades
Limitations
- Low electrical conductivity — 4.6 % IACS, worse than 96% of copper alloy grades
- High embodied carbon — 7 kg CO₂/kg, worse than 96% of copper alloy grades
- Poor heat conductor — 29 W/m·K (16.8 BTU/hr·ft·°F), worse than 93% of copper alloy grades
C71500-H55 properties
Typical room-temperature values for C71500-H55; 20 are specific to this condition. Other listed values are C71500 reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
C71500-H55 has a density of 8.94 g/cm³ (0.323 lb/in³), heavier than 90% of copper alloy grades. It melts at 1,171°C (2,140 °F).
Mechanical14
C71500-H55 has a yield strength of 275 MPa (39.9 ksi) and a tensile strength of 415 MPa (60.2 ksi) — stronger than 57% of copper alloy grades. Elongation at break is 30% and the elastic modulus is 152 GPa (22 Msi).
Thermal6
C71500-H55 is rated for continuous service to 350°C (662 °F). It conducts heat at 29 W/m·K (16.8 BTU/hr·ft·°F), worse than 93% of copper alloy grades. Thermal expansion is 16.2 µm/m·K (9 µin/in·°F).
Electrical3
C71500-H55 conducts electricity at 4.6 % IACS, worse than 96% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is very good (82/100), better than 98% of copper alloy grades.
Sustainability4
Producing a kilogram of C71500-H55 takes about 110 MJ of energy and emits 7 kg of CO₂ — more than 97% of copper alloy grades. Typical recycled content is 30%.
Manufacturability8
C71500-H55's machinability is fair (35/100, better than 51% of copper alloy grades); weldability very good (82/100); formability very good (70/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with C71500-H55
Is C71500 easy to machine?
Gummy and work-hardening (≈20 % of AISI 1212) — use sharp positive-rake carbide, heavy positive feed, rigid setup and flood coolant to avoid rubbing.
Can C71500 be welded?
Excellent with GTAW/GMAW using ERCuNi (70/30) filler under argon; keep interpass low, avoid oxide/S/Pb contamination and do not use preheat.
Can C71500 be formed, bent or molded?
Very good cold formability in O61 (deep drawing, tube bending, expanding); hot work 900–1050 °C only, anneal 700–850 °C followed by rapid cool.
What surface finishes work on C71500?
Not anodizable; polishes to a bright silver-grey, develops a protective adherent film in seawater — allow film formation at low flow before high-velocity service, or apply tin/nickel plating.
C71500 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 |
|---|---|---|
| NiNi + Co per ASTM B111/B171 | 29 – 33 | 31 |
| Feimproves impingement/erosion resistance | 0.4 – 1 | 0.6 |
| Mndeoxidiser; GB/T BFe30-1-1 nominal ≈ 1 % | 0 – 1 | 0.7 |
| Zn | ≤ 1 | — |
| Pb | ≤ 0.05 | — |
| C | ≤ 0.05 | — |
| S | ≤ 0.02 | — |
| P | ≤ 0.02 | — |
| Curemainder, ~67–70 % | balance | — |
C71500-H55 — frequently asked
What is C71500-H55 used for?
C71500-H55 is typically used for marine hardware, heat exchanger tubing fittings and desalination components. In short: best seawater corrosion resistance; very formable copper-nickel; standard 70/30 marine alloy.
What is the yield strength of C71500-H55?
C71500-H55 has a typical yield strength of 275 MPa (39.9 ksi) and a tensile strength of 415 MPa (60.2 ksi) — stronger than 57% of copper alloy grades. Strength varies by condition: see the 9 listed tempers.
Is C71500-H55 easy to machine?
Not especially — machinability is rated fair (35/100, better than 51% of copper alloy grades). Gummy and work-hardening (≈20 % of AISI 1212) — use sharp positive-rake carbide, heavy positive feed, rigid setup and flood coolant to avoid rubbing.
Can C71500-H55 be welded?
Yes — weldability is rated very good (82/100). Excellent with GTAW/GMAW using ERCuNi (70/30) filler under argon; keep interpass low, avoid oxide/S/Pb contamination and do not use preheat.
What surface finishes work on C71500-H55?
Not anodizable; polishes to a bright silver-grey, develops a protective adherent film in seawater — allow film formation at low flow before high-velocity service, or apply tin/nickel plating.
Can C71500-H55 be formed, bent or molded?
Very good cold formability in O61 (deep drawing, tube bending, expanding); hot work 900–1050 °C only, anneal 700–850 °C followed by rapid cool.
What is the maximum service temperature of C71500-H55?
C71500-H55 is rated for continuous use to about 350°C (662 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between C71500-O61 and C71500-H80?
O61 is the default condition — default stock condition for tube, plate and sheet — maximum ductility for bending, expanding and welding. H80: maximum as-drawn strength for shafting, wire and high-pressure small-bore tube. Yield strength is 140 MPa in O61 versus 545 MPa in H80.
Sources
- ASTM B111/B111M — Copper and Copper-Alloy Seamless Condenser Tubes — ASTM (2021)
- ASTM B171/B171M — Copper-Alloy Plate for Condensers and Heat Exchangers — ASTM (2018)
- GB/T 2059 / GB/T 8890 (BFe30-1-1) — SAC (2017)
- CDA Alloy Datasheet C71500 — Copper Development Association (copper.org) (2023)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- Copper-Nickel Alloys: Properties and Applications — Nickel Institute / CDA UK (2020)
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.