Copper Alloy C73200
UNS C73200
A copper-nickel-zinc (nickel silver) alloy with lower nickel content than 65-10 grades, used for decorative hardware and musical instrument components where a warm silvery finish and formability are needed.
Reference datasheet — C73200 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the H02 condition
C73200 tempers and conditions
C73200 is supplied in 10 conditions, soft to hard. H02 is the default FabDigit quotes; the values on this page are for it.
Compare all 10 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Soft annealed | Pick for deep drawing, spinning, severe bending and stamping of decorative parts. | 125 | 380 | 40 | 70 HB | — |
As hot rolled | Mill-finished hot-worked bar or plate for parts that will be machined all over. | 165 | 400 | 35 | 75 HB | 11.5 % IACS |
Quarter hard | Pick when moderate bending is still needed but annealed strip is too soft to handle. | 275 | 415 | 25 | 105 HB | 11 % IACS |
Light drawn | Pick for nickel silver tube that must still be bent or expanded after drawing. | 275 | 430 | 22 | 105 HB | 11 % IACS |
H02Default Half hard | Default stocked strip/rod temper: balance of strength, mild formability and a surface that polishes well. | 380 | 470 | 12 | 130 HB | 11 % IACS |
Three-quarter hard | Intermediate temper for flat parts that need extra stiffness with only slight forming. | 420 | 505 | 8 | 145 HB | 10.8 % IACS |
Full hard | Pick for flat springs, stiff trim and parts blanked with minimal bending. | 450 | 540 | 5 | 155 HB | 10.7 % IACS |
Extra hard | Pick for high-stiffness flat stock and light spring contacts; forming is limited to gentle radii. | 510 | 590 | 3 | 175 HB | 10.6 % IACS |
Spring hard | Pick for springy clips and instrument parts needing high elastic limit. | 545 | 635 | 2 | 185 HB | 10.5 % IACS |
Extra spring hard | Highest-strength rolled temper; only for flat springs bent along preferred direction. | 585 | 680 | 2 | 200 HB | 10.5 % IACS |
What is C73200?
A copper-nickel-zinc (nickel silver) alloy with lower nickel content than 65-10 grades, used for decorative hardware and musical instrument components where a warm silvery finish and formability are needed. C73200 has a density of 8.73 g/cm³ (0.315 lb/in³), lighter than 53% of copper alloy grades. It melts at 1,060°C (1,940 °F). C73200 has a yield strength of 380 MPa (55.1 ksi) and a tensile strength of 470 MPa (68.2 ksi) — stronger than 77% of copper alloy grades. Elongation at break is 12% and the elastic modulus is 125 GPa (18.1 Msi).
What is C73200 used for?
- decorative hardware
- musical instrument parts
- costume jewelry
- flatware
Advantages
- Polishes to a fine finish — 90/100, better than 99% of copper alloy grades
- Forms and bends easily — 70/100, better than 80% of copper alloy grades
- High strength — 380 MPa (55.1 ksi), better than 77% of copper alloy grades
Limitations
- Difficult to machine — 25/100, worse than 86% of copper alloy grades
- High embodied carbon — 4.3 kg CO₂/kg, worse than 77% of copper alloy grades
- Poor heat conductor — 45 W/m·K (26 BTU/hr·ft·°F), worse than 76% of copper alloy grades
C73200 properties
Typical room-temperature values for C73200-H02; bars are the position among copper alloy grades.
Physical3
C73200 has a density of 8.73 g/cm³ (0.315 lb/in³), lighter than 53% of copper alloy grades. It melts at 1,060°C (1,940 °F).
Mechanical15
C73200 has a yield strength of 380 MPa (55.1 ksi) and a tensile strength of 470 MPa (68.2 ksi) — stronger than 77% of copper alloy grades. Elongation at break is 12% and the elastic modulus is 125 GPa (18.1 Msi).
Thermal6
C73200 is rated for continuous service to 200°C (392 °F). It conducts heat at 45 W/m·K (26 BTU/hr·ft·°F), worse than 76% of copper alloy grades. Thermal expansion is 16.2 µm/m·K (9 µin/in·°F).
Electrical3
C73200 conducts electricity at 11 % IACS, worse than 68% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (65/100), better than 58% of copper alloy grades.
Sustainability4
Producing a kilogram of C73200 takes about 62 MJ of energy and emits 4.3 kg of CO₂ — more than 76% of copper alloy grades. Typical recycled content is 40%.
Manufacturability7
C73200's machinability is poor (25/100, worse than 86% of copper alloy grades); weldability good (55/100); formability very good (70/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the copper alloy family
Yield strength against density for every copper alloy grade FabDigit runs. C73200 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with C73200
Is C73200 easy to machine?
Gummy, non-free-cutting: use sharp positive-rake carbide, moderate speed, generous soluble-oil coolant and chip breakers; expect ~20 % of AISI 1212 productivity.
Can C73200 be welded?
Best joined by resistance spot/seam, silver brazing or soft soldering; TIG/GTAW is possible with matching or Cu-Ni filler but zinc fume and hot-short cracking demand fume extraction and low heat input.
Can C73200 be formed, bent or molded?
Excellent deep-drawing and stamping in O60/H01; interstage anneal at 600–750 °C and stress-relieve cold-worked parts at ~250–300 °C to avoid ammonia stress-corrosion cracking.
C73200 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 |
|---|---|---|
| Ninominal nickel level for this high-copper nickel silver; verify against mill certificate | 9 – 11 | 10 |
| Znremainder of the alloying addition | 8 – 11 | 9.5 |
| Mndeoxidiser addition typical of nickel silvers | ≤ 0.5 | 0.2 |
| Feimpurity limit | ≤ 0.25 | |
| Pbunleaded grade | ≤ 0.05 | |
| CuCu + Ni + Zn ≥ 99.5 % | balance |
What surface finishes work on C73200?
Buffs to a bright silver-white finish and takes nickel, silver, chrome or gold plating readily; lacquer or clear coat to keep the finish from dulling outdoors.
Surface treatments FabDigit runs on copper alloy parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
How much does C73200 cost?
C73200 is a high-cost copper alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
C73200 — frequently asked
What is C73200 used for?
C73200 is typically used for decorative hardware, musical instrument parts, costume jewelry and flatware. In short: silver-white without silver; lower-nickel nickel silver; deep-draws and buffs well.
What is the yield strength of C73200?
C73200 has a typical yield strength of 380 MPa (55.1 ksi) and a tensile strength of 470 MPa (68.2 ksi) — stronger than 77% of copper alloy grades. Strength varies by condition: see the 10 listed tempers.
Is C73200 easy to machine?
Not especially — machinability is rated poor (25/100, worse than 86% of copper alloy grades). Gummy, non-free-cutting: use sharp positive-rake carbide, moderate speed, generous soluble-oil coolant and chip breakers; expect ~20 % of AISI 1212 productivity.
Can C73200 be welded?
Yes — weldability is rated good (55/100). Best joined by resistance spot/seam, silver brazing or soft soldering; TIG/GTAW is possible with matching or Cu-Ni filler but zinc fume and hot-short cracking demand fume extraction and low heat input.
What surface finishes work on C73200?
Buffs to a bright silver-white finish and takes nickel, silver, chrome or gold plating readily; lacquer or clear coat to keep the finish from dulling outdoors.
Can C73200 be formed, bent or molded?
Excellent deep-drawing and stamping in O60/H01; interstage anneal at 600–750 °C and stress-relieve cold-worked parts at ~250–300 °C to avoid ammonia stress-corrosion cracking.
What is the maximum service temperature of C73200?
C73200 is rated for continuous use to about 200°C (392 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between C73200-H02 and C73200-O60?
H02 is the default condition — default stocked strip/rod temper: balance of strength, mild formability and a surface that polishes well. O60: pick for deep drawing, spinning, severe bending and stamping of decorative parts. Yield strength is 380 MPa in H02 versus 125 MPa in O60.
How much does C73200 cost?
C73200 is a high-cost copper alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- ASM Handbook, Vol. 2: Properties and Selection — Nonferrous Alloys (Cu-Ni-Zn nickel silvers) — ASM International (1990)
- Copper Alloy Data — Wrought Nickel Silvers (C73xxx–C79xxx) — Copper Development Association (copper.org) (2023)
- ASTM B122/B122M — Copper-Nickel-Tin, Copper-Nickel-Zinc Plate, Sheet, Strip and Rolled Bar — ASTM International (2022)
- ASTM B151/B151M — Copper-Nickel-Zinc (Nickel Silver) and Copper-Nickel Rod and Bar — ASTM International (2019)
- ASTM B601 — Temper Designations for Copper and Copper Alloys — ASTM International (2019)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.