Copper Alloy C73200-H03
Supply condition
UNS C73200
H03 = three-quarter hard
Intermediate temper for flat parts that need extra stiffness with only slight forming.
Values for the H03 condition
Other C73200 tempers and conditions
C73200 is listed in 10 conditions; see the grade overview at C73200.
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 |
H03This page 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-H03?
C73200-H03 is C73200 supplied in the H03 condition — intermediate temper for flat parts that need extra stiffness with only slight forming. C73200-H03 has a yield strength of 420 MPa (60.9 ksi) and a tensile strength of 505 MPa (73.2 ksi) — stronger than 83% of copper alloy grades. Elongation at break is 8% and the elastic modulus is 126 GPa (18.3 Msi). C73200-H03 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). H02 is the default condition FabDigit quotes; H03 is available on request or by drawing note.
Advantages
- Polishes to a fine finish — 90/100, better than 99% of copper alloy grades
- High strength — 420 MPa (60.9 ksi), better than 83% of copper alloy grades
Limitations
- Limited service temperature — 175°C (347 °F), worse than 92% of copper alloy grades
- Limited ductility — 8%, worse than 83% 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-H03 properties
Typical room-temperature values for C73200-H03; 21 are specific to this condition. Other listed values are C73200 reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
C73200-H03 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-H03 has a yield strength of 420 MPa (60.9 ksi) and a tensile strength of 505 MPa (73.2 ksi) — stronger than 83% of copper alloy grades. Elongation at break is 8% and the elastic modulus is 126 GPa (18.3 Msi).
Thermal6
C73200-H03 is rated for continuous service to 175°C (347 °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-H03 conducts electricity at 10.8 % IACS, worse than 72% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (64/100), better than 52% of copper alloy grades.
Sustainability4
Producing a kilogram of C73200-H03 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-H03's machinability is poor (27/100, worse than 81% of copper alloy grades); weldability fair (52/100); formability good (55/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with C73200-H03
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.
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.
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 | — |
C73200-H03 — frequently asked
What is C73200-H03 used for?
C73200-H03 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-H03?
C73200-H03 has a typical yield strength of 420 MPa (60.9 ksi) and a tensile strength of 505 MPa (73.2 ksi) — stronger than 83% of copper alloy grades. Strength varies by condition: see the 10 listed tempers.
Is C73200-H03 easy to machine?
Not especially — machinability is rated poor (27/100, worse than 81% 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-H03 be welded?
With care — weldability is rated fair (52/100). 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-H03?
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-H03 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-H03?
C73200-H03 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 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.
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. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.