Corrosion & Surface Engineering8–10 min read
Choosing Corrosion-Resistant Alloys for Marine Hardware
Saltwater hardware needs a review of crevices, flow, load and maintenance as well as alloy chemistry.
Author: Mat Grades Editorial DeskRead Guide →
C70600 Copper-Nickel 90/10
Primary Designation:UNS C70600
Aliases:
Copper-Nickel 90/10Cupronickel 90-10C70600
Mat Grades internal verification confirms source-backed fidelity and data integrity. It does not constitute external certification or guaranteed lot conformity. Read engineering disclaimer →
Data Completeness:6 composition elements and 41 condition-specific property values cataloged.
Omitted fields represent unverified properties. "Missing is better than invented."
Key Engineering Properties
Representative source rows, qualified by their reported conditions. Inspect the tables below for all values, limits, and source notes.
Density
8.941 g/cm³TYPICAL · at 20 °C
Electrical Conductivity
9 % IACSTYPICAL · at 20 °C
Thermal Conductivity
45 W/(m·K)TYPICAL · at 20 °C
Specific Heat Capacity
376.8 J/(kg·K)TYPICAL · at 20 °C
Melting Range (Solidus / Liquidus)
1098.9 – 1148.9 °C2010.0 – 2100.0 °F
Solidus: 1098.9°C | Liquidus: 1148.9°CComposition Excerpt
Cu BALANCE wt%Copper (balance)
Standard Elemental Basis: BALANCEEngineering Summary
UNS C70600 Copper-Nickel (90Cu-10Ni with 1.0-1.8% Fe) is the premier marine engineering alloy for seawater piping, condenser tubes, offshore oil platform cladding, and ship hulls. It provides outstanding inherent resistance to marine biofouling, velocity-resilient impingement corrosion resistance, and excellent butt-welding and brazing characteristics.
C70600 Copper-Nickel 90/10 Documented Applications
- ›Automotive: Brake Lines
- ›Boat Hulls: Corrosion Resistance
- ›Boat Hulls: Fouling Resistance
- ›Boat Hulls: Mechanical Properties
- ›Brake Lines: Machining Characteristics
- ›Brake Lines: Mechanical Properties
- ›Condenser Plates: Corrosion Resistance
- ›Condenser Plates: Mechanical Properties
- ›Condensers: Corrosion Resistance
- ›Condensers: Mechanical Properties
- ›Consumer: Screw Lamp Bases
- ›Distiller Tubes: Corrosion Resistance
Recognized Aliases
Source-backed commercial trade name and short designations cataloged in canonical data.
Copper-Nickel 90/10Cupronickel 90-10C70600
C70600 Copper-Nickel 90/10 Specifications & Designations
Standard Designations & Applicable Specifications — Semantically classified designations distinguishing primary standard identifiers, commercial trade names, and applicable specification references.
Direct Standard DesignationsDIRECT DESIGNATION
2 Primary IdentifiersScroll horizontally for full designation data
| System | Identifier | Standard System Name | Classification Notes & Provenance |
|---|---|---|---|
| UNSPRIMARY | C70600 | Unified Numbering System | Unified Numbering System standard designation for copper alloys (CDA / SAE / ASTM)Ref: CDA UNS Standard Designations Register (C70600) |
| CDA | Alloy 706 | Copper Development Association Alloy Number | CDA three-digit legacy designationRef: CDA UNS Standard Designations Register (C70600) |
Recognized Commercial Aliases & Trade NamesCOMMON ALIAS
4 ListedScroll horizontally for full alias classifications
| Recognized Name / Alias | Classification | Technical Usage & Context |
|---|---|---|
| 90/10 Cupronickel | Standard Commercial Name | CDA Standard Commercial Name |
| Copper-Nickel 90/10 | Commercial Alias | Colloquial or commercial industry synonym |
| Cupronickel 90-10 | Commercial Alias | Colloquial or commercial industry synonym |
| C70600 | Commercial Alias | Colloquial or commercial industry synonym |
Applicable Specifications & Product Form ReferencesSPECIFICATION REFERENCE
12 Applicable StandardsScroll horizontally for full standard specifications
| Standards Body | Specification Code | Specification Title / Scope | Relationship Type |
|---|---|---|---|
| ASTM | ASTM B122/B122M | COPPER-NICKEL-ZINC ALLOY (NICKEL-SILVER) AND COPPER-NICKEL PLATE, SHEET, STRIP, AND ROLLED BAR | Specification Reference |
| ASTM | ASTM B151/B151M | COPPER-NICKEL-ZINC ALLOY (NICKEL-SILVER) AND COPPER-NICKEL ROD AND BAR | Specification Reference |
| MILITARY | MILITARY MIL-C-15726 | COPPER-NICKEL ALLOY ROD, FLAT PRODUCTS (FLAT WIRE, STRIP, SHEET, BAR, AND PLATE) AND FORGINGS | Specification Reference |
| ASTM | ASTM B956/B956M | WELDED COPPER AND COPPER-ALLOY CONDENSER AND HEAT EXCHANGER TUBES WITH INTEGRAL FINS | Specification Reference |
| ASTM | ASTM B466/B466M | SEAMLESS COPPER-NICKEL PIPE AND TUBE | Specification Reference |
| ASTM | ASTM B467 | WELDED COPPER-NICKEL PIPE | Specification Reference |
| ASME | ASME SB467 | WELDED COPPER-NICKEL PIPE | Specification Reference |
| ASME | ASME SB466 | SEAMLESS COPPER-NICKEL PIPE AND TUBE | Specification Reference |
| ASTM | ASTM B432 | COPPER AND COPPER ALLOY CLAD STEEL PLATE | Specification Reference |
| ASME | ASME SB171 | COPPER ALLOY CONDENSER TUBE PLATES | Specification Reference |
| SAE | SAE J463 | WROUGHT COPPER AND COPPER ALLOYS | Specification Reference |
| SAE | SAE J461 | WROUGHT AND CAST COPPER ALLOYS | Specification Reference |
Engineering Notice: Applicable specifications establish manufacturing requirements, dimensional tolerances, and test criteria for specific product forms (e.g. bus bar, wire, plate, pipe). They represent applicable technical standards, not alternative or equivalent alloy grades.
C70600 Copper-Nickel 90/10 Chemical Composition
Chemical Composition (Weight %) — Elemental limits and values from the cited source. Preserves exact semantic limits (minimums, maximums, and ranges).
Scroll horizontally for full elemental limits
| Element | Symbol | Atomic No. | Semantic Basis | Specified Value | Unit | Metallurgical Notes & Qualification | Data Status |
|---|---|---|---|---|---|---|---|
| Copper | Cu | 29 | BALANCE | Balance | wt% | Remainder element (Copper).Ref: Copper Development Association (CDA) | VERIFIED |
| Lead | Pb | 82 | MAXIMUM | ≤ 0.05 | wt% | CDA chemical composition specification limits for C70600: max 0.05 wt%.Ref: Copper Development Association (CDA) | VERIFIED |
| Zinc | Zn | 30 | MAXIMUM | ≤ 1.00 | wt% | CDA chemical composition specification limits for C70600: max 1.0 wt%.Ref: Copper Development Association (CDA) | VERIFIED |
| Iron | Fe | 26 | RANGE | 1.00 – 1.80 | wt% | CDA chemical composition specification limits for C70600: 1.0 - 1.8 wt%.Ref: Copper Development Association (CDA) | VERIFIED |
| Nickel | Ni | 28 | RANGE | 9.00 – 11.00 | wt% | CDA chemical composition specification limits for C70600: 9.0 - 11.0 wt%.Ref: Copper Development Association (CDA) | VERIFIED |
| Manganese | Mn | 25 | MAXIMUM | ≤ 1.00 | wt% | CDA chemical composition specification limits for C70600: max 1.0 wt%.Ref: Copper Development Association (CDA) | VERIFIED |
* Elemental percentages are expressed in weight percent (wt%). Values represent applicable specification limits. Unspecified trace elements are not fabricated or assumed.Preserves exact semantic basis
Property Display UnitsSwitch between Canonical SI and Source / US Customary units:
C70600 Copper-Nickel 90/10 Physical Properties
Source-specific physical properties. Test temperatures are shown only where reported.
Scroll horizontally for full property parameters
| Property Parameter | Canonical SI Value | Semantic Basis | Test Temperature / Context Range | Source Raw Reference | Source Reference | Status |
|---|---|---|---|---|---|---|
| Density | 8.941 g/cm³ | TYPICAL | Test Temp: 20 °CCDA Physical Properties: Density 0.323 lb/cu in. at 68°F (8.941 g/cm³ at 20°C) | 0.323 lb/cu in. at 68°F | Copper Development Association Inc. | VERIFIED |
C70600 Copper-Nickel 90/10 Thermal & Thermodynamic Properties
Phase change temperatures, thermal conductivity, specific heat, mean coefficients of thermal expansion across standardized temperature ranges, and recommended thermal processing windows.
Scroll horizontally for full property parameters
| Property Parameter | Canonical SI Value | Semantic Basis | Test Temperature / Context Range | Source Raw Reference | Source Reference | Status |
|---|---|---|---|---|---|---|
| Liquidus Temperature | 1148.9 °C | TYPICAL | CDA Physical Properties: Liquidus temperature 2100.0 °F (1148.9 °C) | 2100.0 °F | Copper Development Association Inc. | VERIFIED |
| Solidus Temperature | 1098.9 °C | TYPICAL | CDA Physical Properties: Solidus temperature 2010.0 °F (1098.9 °C) | 2010.0 °F | Copper Development Association Inc. | VERIFIED |
| Thermal Conductivity | 45 W/(m·K) | TYPICAL | Test Temp: 20 °CCDA Physical Properties: Thermal conductivity 26.0 Btu/(ft·hr·°F) (45.0 W/(m·K) at 20°C) | 26.0 Btu/ sq ft/ ft hr/ °F at 68°F | Copper Development Association Inc. | VERIFIED |
| Coefficient of Thermal Expansion (CTE) | 17.1 µm/(m·K) | TYPICAL | CDA Physical Properties: CTE 9.5 µin/(in·°F) (17.1 µm/(m·K)) over range 68-57210°F | 9.5 10^-6 per °F | Copper Development Association Inc. | VERIFIED |
| Specific Heat Capacity | 376.8 J/(kg·K) | TYPICAL | Test Temp: 20 °CCDA Physical Properties: Specific heat 0.09 Btu/(lb·°F) (376.8 J/(kg·K)) | 0.09 Btu/ lb /°F at 68°F | Copper Development Association Inc. | VERIFIED |
| Annealing Temperature Range | 593.3 – 815.6 °C | RANGE | CDA Thermal Treatments: Annealing temperature range 1100 - 1500°F (593.3 - 815.6°C) | 1100 – 1500 °F | Copper Development Association Inc. | VERIFIED |
| Hot Working Temperature Range | 843.3 – 954.4 °C | RANGE | CDA Thermal Treatments: Hot working range 1550 - 1750°F (843.3 - 954.4°C) | 1550 – 1750 °F | Copper Development Association Inc. | VERIFIED |
C70600 Copper-Nickel 90/10 Electrical Properties
Electrical conductivity and resistivity in their reported units and conditions.
Scroll horizontally for full property parameters
| Property Parameter | Canonical SI Value | Semantic Basis | Test Temperature / Context Range | Source Raw Reference | Source Reference | Status |
|---|---|---|---|---|---|---|
| Electrical Conductivity | 9 % IACS | TYPICAL | Test Temp: 20 °CCDA Physical Properties: Volume conductivity 9.0 % IACS at 68°F (20°C) | 9.0 % IACS at 68°F | Copper Development Association Inc. | VERIFIED |
C70600 Copper-Nickel 90/10 Mechanical Properties
Contextual Mechanical Properties & Tempers: Engineering strength, ductility, and hardness values grouped by product form, temper, and section thickness. Mechanical properties are contextual and not isotropic averages.
Elastic & Baseline Mechanical ConstantsSource-specific measurement conditions
Modulus of Elasticity (Tension)
124.1 GPa
CDA Physical Properties: Elastic modulus in tension 18000.0 ksi (124.1 GPa)Modulus of Rigidity
46884.3 MPa
CDA Physical Properties: Shear modulus 6800.0 ksi (46884.3 MPa)Machinability Rating
20 %
CDA Fabrication Properties: Rating relative to Free-Cutting Brass (C36000 = 100%).Showing 12 of 12 conditions
Scroll horizontally for all conditions & tempers
| Product Form | Temper / Condition | Section Size | Tensile (UTS) | Yield Strength | Elongation | Shear Strength | Fatigue Strength | Hardness (Scales Preserved) | Status |
|---|---|---|---|---|---|---|---|---|---|
| Bar | Hard (H04) · 20 °CSource values and qualifiersTensile Strength: 344.7 MPa (TYPICAL)Copper Development Association (CDA) — Yield Strength (0.5% Ext): 172.4 MPa (TYPICAL)Yield strength at 0.5% extension under loadCopper Development Association (CDA) — Elongation: 15 % (TYPICAL)Copper Development Association (CDA) — | — | 344.7 MPa | 172.4 MPa | 15 % | — | — | — | VERIFIED |
| Bar | Soft Anneal (O60) · 20 °CSource values and qualifiersTensile Strength: 262 MPa (TYPICAL)Copper Development Association (CDA) — Yield Strength (0.5% Ext): 103.4 MPa (TYPICAL)Yield strength at 0.5% extension under loadCopper Development Association (CDA) — Elongation: 30 % (TYPICAL)Copper Development Association (CDA) — | — | 262 MPa | 103.4 MPa | 30 % | — | — | — | VERIFIED |
| Flat Products | 1/4 Hard (H01) · 20 °CSource values and qualifiersTensile Strength: 365.4 MPa (TYPICAL)Copper Development Association (CDA) — Yield Strength (0.5% Ext): 110.3 MPa (TYPICAL)Yield strength at 0.5% extension under loadCopper Development Association (CDA) — Elongation: 35 % (TYPICAL)Copper Development Association (CDA) — | — | 365.4 MPa | 110.3 MPa | 35 % | — | — | — | VERIFIED |
| Flat Products | 1/4 Hard (H01)Source values and qualifiersRockwell B Hardness: 60 HRB (TYPICAL)Copper Development Association (CDA) — | — | — | — | — | — | — | 60 HRB | VERIFIED |
| Flat Products | As Hot Rolled (M20) · 20 °CSource values and qualifiersTensile Strength: 275.8 MPa (TYPICAL)Copper Development Association (CDA) — Yield Strength (0.5% Ext): 103.4 MPa (TYPICAL)Yield strength at 0.5% extension under loadCopper Development Association (CDA) — Elongation: 30 % (TYPICAL)Copper Development Association (CDA) — | — | 275.8 MPa | 103.4 MPa | 30 % | — | — | — | VERIFIED |
| Flat Products | As Hot Rolled (M20)Source values and qualifiersRockwell B Hardness: 3 HRB (TYPICAL)Copper Development Association (CDA) — | — | — | — | — | — | — | 3 HRB | VERIFIED |
| Flat Products | Hard (H04) · 20 °CSource values and qualifiersTensile Strength: 517.1 MPa (TYPICAL)Copper Development Association (CDA) — Yield Strength (0.5% Ext): 503.3 MPa (TYPICAL)Yield strength at 0.5% extension under loadCopper Development Association (CDA) — Elongation: 5 % (TYPICAL)Copper Development Association (CDA) — | — | 517.1 MPa | 503.3 MPa | 5 % | — | — | — | VERIFIED |
| Flat Products | Hard (H04)Source values and qualifiersRockwell B Hardness: 80 HRB (TYPICAL)Copper Development Association (CDA) — | — | — | — | — | — | — | 80 HRB | VERIFIED |
| Tube | Annealed (O61) · 20 °CSource values and qualifiersTensile Strength: 303.4 MPa (TYPICAL)Copper Development Association (CDA) — Yield Strength (0.5% Ext): 110.3 MPa (TYPICAL)Yield strength at 0.5% extension under loadCopper Development Association (CDA) — Elongation: 42 % (TYPICAL)Copper Development Association (CDA) — | — | 303.4 MPa | 110.3 MPa | 42 % | — | — | — | VERIFIED |
| Tube | Annealed (O61)Source values and qualifiersRockwell B Hardness: 15 HRB (TYPICAL)Copper Development Association (CDA) — Rockwell F Hardness: 65 HRF (TYPICAL)Copper Development Association (CDA) — Rockwell 30T Hardness: 26 HR30T (TYPICAL)Copper Development Association (CDA) — | — | — | — | — | — | — | 15 HRB65 HRF26 HR30T | VERIFIED |
| Tube | Light Drawn, Light Cold Rolled (H55) · 20 °CSource values and qualifiersTensile Strength: 310.3 MPa (TYPICAL)Copper Development Association (CDA) — Elongation: 10 % (TYPICAL)Copper Development Association (CDA) — | — | 310.3 MPa | — | 10 % | — | — | — | VERIFIED |
| Tube | Light Drawn, Light Cold Rolled (H55)Source values and qualifiersRockwell B Hardness: 72 HRB (TYPICAL)Copper Development Association (CDA) — Rockwell F Hardness: 100 HRF (TYPICAL)Copper Development Association (CDA) — Rockwell 30T Hardness: 70 HR30T (TYPICAL)Copper Development Association (CDA) — | — | — | — | — | — | — | 72 HRB100 HRF70 HR30T | VERIFIED |
Hardness Integrity Notice: Rockwell B (HRB), Rockwell F (HRF), and Superficial 30T (HR30T) scales are reported on their measured scales without cross-scale mathematical conversion.
Source: See fact-level citations
C70600 Copper-Nickel 90/10 Processing & Fabrication
Machining, joining, forming, and thermal processing ratings cataloged from the cited authoritative technical reference.
Machinability
Machinability rating: 20% relative to free-cutting brass (C36000 = 100%).
Weldability & Joining
Soldering: Excellent; Brazing: Excellent; Oxyacetylene Welding: Fair; Gas Shielded Arc Welding: Excellent; Coated Metal Arc Welding: Good; Spot Weld: Good; Seam Weld: Good; Butt Weld: Excellent
Heat Treatment & Working Ranges
Annealing temperature range: 593.3°C to 815.6°C (1100°F - 1500°F). Hot working temperature range: 843.3°C to 954.4°C (1550°F - 1750°F).
Forming & Cold Working
Capacity for Being Cold Worked: Good. Capacity for Being Hot Formed: Good.
Practical Engineering & Fabrication Notes
By Mat Grades Editorial Desk · Updated 2026-11-14. Use alongside the specified product standard and supplier certificate.
Machining & shop-floor behavior
The cataloged machining note for C70600 Copper-Nickel 90/10 states: Machinability rating: 20% relative to free-cutting brass (C36000 = 100%). A relevant hardness example is Rockwell B Hardness: 60 HRB (typical; 1/4 Hard (H01), H01, Flat Products). Use that supplied condition for a trial of the difficult feature. Record tool changes, burr removal, unclamped dimensions and accepted parts per hour. Relative machinability ratings from different reference scales should not be compared as if they were one common test.
Weldability, brazing & joining
The available joining assessment states: Soldering: Excellent; Brazing: Excellent; Oxyacetylene Welding: Fair; Gas Shielded Arc Welding: Excellent; Coated Metal Arc Welding: Good; Spot Weld: Good; Seam Weld: Good; Butt Weld: Excellent The first cataloged strength example is Tensile Strength: 344.7 MPa (typical; Hard (H04), H04, Bar; test temperature 20 °C). Assess the final part after joining or thermal processing. Include distortion, cleanup and inspection in the quotation. A material designation or favorable process rating is a starting point for qualification, not evidence that an untested joint meets the drawing.
Corrosion & service environment
Review the working fluid, cleaning agents and dissimilar-metal contacts as separate exposures. The word copper, brass or bronze is too broad to establish compatibility. A process rating does not qualify a pressure boundary, and a thermal-property measurement does not establish a continuous service-temperature limit. The recorded thermal example is Thermal Conductivity: 45 W/(m·K) (typical; ; test temperature 20 °C). State the exposure and inspection access in the design record so that a change of installation or cleaning method triggers a review. The selected composition entries are Pb maximum 0.05 wt%, Zn maximum 1 wt%. Chemistry documents identity; it does not establish fluid compatibility.
Selection trade-offs & applications
Use UNS C70600, COMMERCIAL 90/10 Cupronickel, CDA Alloy 706 to identify the candidate, then specify the product form and delivered condition separately. The catalog lists Automotive: Brake Lines as an application example. The related candidate C71500 Copper-Nickel 70/30 is linked for comparison; its commonly compared relationship must be checked before substitution. Compare the complete route through machining, joining, finish and inspection. Keep the certificate, required test location and acceptance criteria with the first-article record. A later change of grade, condition or source should be assessed against that same requirement.
Technical references: Copper Development Association (CDA); Copper Development Association (CDA)
C70600 Copper-Nickel 90/10 Equivalent & Comparable Grades
Comparable Grades & Cross-References: Carefully classified cross-reference relationships for C70600 Copper-Nickel 90/10. Comparable does not mean equivalent.
Scroll horizontally for relationship classifications & comparisons
| Related Material | Family | Relationship Classification | Metallurgical Notes & Differences | Status | Action |
|---|---|---|---|---|---|
| C71500 Copper-Nickel 70/30 | Copper Alloys | Commonly Compared | C70600 (90/10 Cu-Ni) provides inherent biofouling and seawater corrosion resistance in marine piping systems. C71500 (70/30 Cu-Ni) delivers higher mechanical strength and greater erosion-corrosion resistance in higher-velocity fluid systems.Materials serve different design priorities (e.g. higher strength vs superior corrosion resistance or cost). | VERIFIED |
Copper-Nickel (Cupronickel) Alloy Family
Copper alloys sharing common alloying formulations and metallurgical classifications under the Copper-Nickel (Cupronickel) branch.
C70600Current Grade
C70600 Copper-Nickel 90/10
Related Engineering & Metallurgy Guides
Contextual technical guides explaining degradation mechanisms, testing methodologies, and selection criteria relevant to C70600 Copper-Nickel 90/10.
Sources
Sources & Provenance Trail: Authoritative reference publications, standards specifications, and data registers cited across this material record.
Copper Development Association Inc.CDA Alloy C70600 Property & Specification Profile
AUTHORITATIVE BODY
Copper Development Association authoritative technical reference profile for C70600 Copper-Nickel 90/10.
Issuing Body: Copper Development Association (CDA)View Source Record ↗
Copper Development Association Inc.CDA UNS Standard Designations Register (C70600)
AUTHORITATIVE BODY
Unified Numbering System (UNS) designation registration register confirming active C70600 status.
Issuing Body: Copper Development Association (CDA)View Source Record ↗
Intellectual Property & Provenance Notice: Mat Grades cites technical literature from recognized industry associations and standards organizations. Underlying technical standards and publication data remain the intellectual property of their respective issuing organizations.