Copper Alloy C72200-H55
Temper
UNS C72200
H55 = light drawn
Lightly drawn tube temper giving straighter, stiffer condenser tubing than annealed while keeping enough ductility for roller expansion into tube sheets.
Values for the H55 condition
Other C72200 tempers and conditions
C72200 is listed in 8 conditions; see the grade overview at C72200.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
As hot rolled | Mill hot-worked plate, bar or extruded tube shell; lowest strength, used where further forming or full annealing follows. | 140 | 360 | 35 | 74 HB | — |
O61Default Annealed | Standard condition for seawater condenser and heat-exchanger tube, tube-sheet cladding and deep-drawn parts; maximum ductility and best corrosion behaviour. | 150 | 385 | 40 | 78 HB | 5.5 % IACS |
H55This page Light drawn | Lightly drawn tube temper giving straighter, stiffer condenser tubing than annealed while keeping enough ductility for roller expansion into tube sheets. | 275 | 415 | 25 | 100 HB | — |
Quarter hard | Mild cold-worked strip/sheet when moderate stiffness is needed but forming and bending are still required. | 340 | 450 | 20 | 115 HB | — |
Half hard | General-purpose cold-rolled temper for sheet parts, ferrules and fittings needing higher yield with some bend capability. | 415 | 495 | 12 | 140 HB | — |
Full hard | High-strength flat product or drawn rod/tube for pressure and structural marine parts where forming is limited to gentle bends. | 500 | 550 | 8 | 160 HB | — |
Extra hard | Heavily cold-worked strip for flat springs, clips and wear surfaces where only very light forming is done. | 540 | 585 | 5 | 175 HB | — |
Spring hard | Maximum cold-worked strength for corrosion-resistant springs, diaphragms and contacts in marine or chemical atmospheres. | 570 | 620 | 4 | 190 HB | — |
What is C72200-H55?
C72200-H55 is C72200 in the H55 temper — lightly drawn tube temper giving straighter, stiffer condenser tubing than annealed while keeping enough ductility for roller expansion into tube sheets. C72200-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 25% and the elastic modulus is 145 GPa (21 Msi). C72200-H55 has a density of 8.94 g/cm³ (0.323 lb/in³), heavier than 90% of copper alloy grades. It melts at 1,130°C (2,066 °F). O61 is the default condition FabDigit quotes; H55 is available on request or by drawing note.
Advantages
- Good corrosion resistance — 82/100, better than 98% of copper alloy grades
- Stiff — 145 GPa (21 Msi), better than 97% of copper alloy grades
- Readily welded — 80/100, better than 93% of copper alloy grades
- Forms and bends easily — 65/100, better than 78% of copper alloy grades
- High service temperature — 260°C (500 °F), better than 75% of copper alloy grades
Limitations
- Low electrical conductivity — 5.5 % IACS, worse than 95% of copper alloy grades
- High embodied carbon — 6.2 kg CO₂/kg, worse than 93% of copper alloy grades
- Poor heat conductor — 34 W/m·K (19.6 BTU/hr·ft·°F), worse than 88% of copper alloy grades
C72200-H55 properties
Typical room-temperature values for C72200-H55; 11 are specific to this condition. Other listed values are C72200 reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
C72200-H55 has a density of 8.94 g/cm³ (0.323 lb/in³), heavier than 90% of copper alloy grades. It melts at 1,130°C (2,066 °F).
Mechanical14
C72200-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 25% and the elastic modulus is 145 GPa (21 Msi).
Thermal6
C72200-H55 is rated for continuous service to 260°C (500 °F). It conducts heat at 34 W/m·K (19.6 BTU/hr·ft·°F), worse than 88% of copper alloy grades. Thermal expansion is 15.7 µm/m·K (8.72 µin/in·°F).
Electrical3
C72200-H55 conducts electricity at 5.5 % IACS, worse than 95% 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 C72200-H55 takes about 92 MJ of energy and emits 6.2 kg of CO₂ — more than 94% of copper alloy grades. Typical recycled content is 30%.
Manufacturability7
C72200-H55's machinability is poor (33/100, worse than 53% of copper alloy grades); weldability very good (80/100); formability good (65/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with C72200-H55
Is C72200 easy to machine?
Gummy and work-hardening like all Cu-Ni: rating ≈20 % of AISI 1212 — use sharp positive-rake carbide, heavy positive feed, low-to-moderate speed and flood coolant to avoid rubbing.
Can C72200 be welded?
Readily GTAW/GMAW welded with 70/30 Cu-Ni (ERCuNi) filler; keep interpass low, no preheat, avoid sulphur/lead/oil contamination and use full penetration to prevent crevices.
Can C72200 be formed, bent or molded?
Excellent cold formability in O61 (deep drawing, tube bending, roller expansion); interanneal near 700–800 °C, hot work 850–1000 °C, and never hot work in sulphur-bearing atmospheres.
What surface finishes work on C72200?
Not anodisable; pickle in sulphuric/hydrogen-peroxide type baths, then leave bare for seawater (protective oxide film) or apply tin, nickel or silver plating for electrical/joining surfaces.
C72200 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 | 15 – 18 | 16.5 |
| Crkey addition for impingement resistance | 0.3 – 0.7 | 0.5 |
| Fe | 0.5 – 1 | 0.7 |
| Mn | ≤ 1 | 0.5 |
| Si | ≤ 0.15 | — |
| Ti | ≤ 0.03 | — |
| Zn | ≤ 0.5 | — |
| C | ≤ 0.05 | — |
| S | ≤ 0.02 | — |
| P | ≤ 0.02 | — |
| Pb | ≤ 0.05 | — |
| Curemainder, ~81–84 % | balance | — |
C72200-H55 — frequently asked
What is C72200-H55 used for?
C72200-H55 is typically used for seawater piping, power plant condenser tubes and high-velocity flow components. In short: chromium-strengthened 90/10 Cu-Ni; high-velocity seawater grade; stronger than C70600.
What is the yield strength of C72200-H55?
C72200-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 8 listed tempers.
Is C72200-H55 easy to machine?
Not especially — machinability is rated poor (33/100, worse than 53% of copper alloy grades). Gummy and work-hardening like all Cu-Ni: rating ≈20 % of AISI 1212 — use sharp positive-rake carbide, heavy positive feed, low-to-moderate speed and flood coolant to avoid rubbing.
Can C72200-H55 be welded?
Yes — weldability is rated very good (80/100). Readily GTAW/GMAW welded with 70/30 Cu-Ni (ERCuNi) filler; keep interpass low, no preheat, avoid sulphur/lead/oil contamination and use full penetration to prevent crevices.
What surface finishes work on C72200-H55?
Not anodisable; pickle in sulphuric/hydrogen-peroxide type baths, then leave bare for seawater (protective oxide film) or apply tin, nickel or silver plating for electrical/joining surfaces.
Can C72200-H55 be formed, bent or molded?
Excellent cold formability in O61 (deep drawing, tube bending, roller expansion); interanneal near 700–800 °C, hot work 850–1000 °C, and never hot work in sulphur-bearing atmospheres.
What is the maximum service temperature of C72200-H55?
C72200-H55 is rated for continuous use to about 260°C (500 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between C72200-O61 and C72200-H08?
O61 is the default condition — standard condition for seawater condenser and heat-exchanger tube, tube-sheet cladding and deep-drawn parts; maximum ductility and best corrosion behaviour. H08: maximum cold-worked strength for corrosion-resistant springs, diaphragms and contacts in marine or chemical atmospheres. Yield strength is 150 MPa in O61 versus 570 MPa in H08.
Sources
- ASTM B111/B111M — Copper and Copper-Alloy Seamless Condenser Tubes — ASTM International (2021)
- ASTM B466/B466M — Seamless Copper-Nickel Pipe and Tube — ASTM International (2020)
- CDA Alloy Database — C72200 Copper-Nickel-Chromium — Copper Development Association (copper.org) (2023)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- Copper-Nickel Alloys: Properties and Applications in Seawater Systems — Nickel Institute / CDA (2018)
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.