Copper Alloy C17460-TH04
Precip hard
UNS C17460 · ASTM B441
TH04 = tD04 and precipitation hardened
Highest strength condition for springs and heavily loaded contacts where ductility can be low.
Values for the TH04 condition
Other C17460 tempers and conditions
C17460 is listed in 8 conditions; see the grade overview at C17460.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution heat treated | Softest condition for deep forming, stamping or machining before customer age hardening. | 170 | 340 | 28 | 95 HB | 28 % IACS |
Solution heat treated and cold worked, full hard | Cold-drawn/rolled but not aged; chosen when the part is formed then age hardened to HT. | 450 | 520 | 10 | 145 HB | 30 % IACS |
Mill hardened, half hard | Mill-hardened strip for formed contacts needing good bend ductility with no customer heat treatment. | 550 | 660 | 14 | 185 HB | 52 % IACS |
TF00Default Solution heat treated and precipitation hardened | Standard stocked rod/bar condition: peak-aged for balanced 700–830 MPa strength with ~50% IACS conductivity. | 620 | 760 | 12 | 95 HRB | 52 % IACS |
Mill hardened, full hard | Mid-range mill-hardened strip temper balancing forming and spring force. | 620 | 730 | 11 | 18 HRC | 52 % IACS |
Mill hardened, extra hard | Common connector strip temper: high contact force with moderate bendability transverse to rolling. | 710 | 800 | 9 | 22 HRC | 50 % IACS |
TH04This page TD04 and precipitation hardened | Highest strength condition for springs and heavily loaded contacts where ductility can be low. | 740 | 830 | 8 | 25 HRC | 50 % IACS |
Mill hardened, spring hard | Highest mill-hardened strength for flat springs and minimal-deflection contacts; limited forming. | 780 | 860 | 7 | 24 HRC | 50 % IACS |
What is C17460-TH04?
C17460-TH04 is C17460 in the TH04 condition — highest strength condition for springs and heavily loaded contacts where ductility can be low. C17460-TH04 has a yield strength of 740 MPa (107 ksi) and a tensile strength of 830 MPa (120 ksi) — stronger than 97% of copper alloy grades. Elongation at break is 8% and the elastic modulus is 138 GPa (20 Msi). C17460-TH04 has a density of 8.83 g/cm³ (0.319 lb/in³), heavier than 65% of copper alloy grades. It melts at 1,000°C (1,832 °F). TF00 is the default condition FabDigit quotes; TH04 is available on request or by drawing note.
Advantages
- High strength — 740 MPa (107 ksi), better than 97% of copper alloy grades
- Stiff — 138 GPa (20 Msi), better than 95% of copper alloy grades
- High service temperature — 320°C (608 °F), better than 93% of copper alloy grades
- Conducts heat well — 225 W/m·K (130 BTU/hr·ft·°F), better than 80% of copper alloy grades
- High electrical conductivity — 50 % IACS, better than 79% of copper alloy grades
Limitations
- High embodied carbon — 6.5 kg CO₂/kg, worse than 94% of copper alloy grades
- Limited ductility — 8%, worse than 83% of copper alloy grades
C17460-TH04 properties
Typical room-temperature values for C17460-TH04; 11 are specific to this condition. Other listed values are C17460 reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
C17460-TH04 has a density of 8.83 g/cm³ (0.319 lb/in³), heavier than 65% of copper alloy grades. It melts at 1,000°C (1,832 °F).
Mechanical13
C17460-TH04 has a yield strength of 740 MPa (107 ksi) and a tensile strength of 830 MPa (120 ksi) — stronger than 97% of copper alloy grades. Elongation at break is 8% and the elastic modulus is 138 GPa (20 Msi).
Thermal6
C17460-TH04 is rated for continuous service to 320°C (608 °F). It conducts heat at 225 W/m·K (130 BTU/hr·ft·°F), better than 80% of copper alloy grades. Thermal expansion is 17.5 µm/m·K (9.72 µin/in·°F).
Electrical3
C17460-TH04 conducts electricity at 50 % IACS, better than 79% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (65/100), better than 58% of copper alloy grades.
Sustainability4
Producing a kilogram of C17460-TH04 takes about 95 MJ of energy and emits 6.5 kg of CO₂ — more than 95% of copper alloy grades. Typical recycled content is 30%.
Manufacturability8
C17460-TH04's machinability is fair (45/100, better than 64% of copper alloy grades); weldability fair (45/100); formability poor (20/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with C17460-TH04
Is C17460 easy to machine?
Machines like a hard bronze — carbide tooling, positive rake, flood coolant; wet-cut and capture fines/dust because of beryllium content (OSHA/ACGIH exposure controls).
Can C17460 be welded?
Resistance and electron-beam welding good; GTAW possible with matching filler but the heat-affected zone loses age-hardened strength and normally needs re-solutioning and re-aging.
Can C17460 be formed, bent or molded?
Form in TB00/TD04 then age (600–800 °F class cycle, roughly 3 h at ~480 °C) for peak properties; mill-hardened TM tempers are formed as delivered with grain-direction bend limits.
What surface finishes work on C17460?
Not anodizable; electroplate Ni barrier plus Sn, Ag or Au for contacts, or passivate/lacquer to limit tarnish; polishes to a bright finish.
C17460 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 |
|---|---|---|
| Beberyllium provides precipitation hardening | 0.15 – 0.5 | 0.3 |
| Ni | 1 – 1.4 | 1.2 |
| Curemainder; named impurities limited per ASTM B441/B534 | balance | — |
C17460-TH04 — frequently asked
What is C17460-TH04 used for?
C17460-TH04 is typically used for connector springs, electronic contacts and relay components. In short: highest service temp in group; low-cobalt connector alloy; limited cold formability.
What is the yield strength of C17460-TH04?
C17460-TH04 has a typical yield strength of 740 MPa (107 ksi) and a tensile strength of 830 MPa (120 ksi) — stronger than 97% of copper alloy grades. Strength varies by condition: see the 8 listed tempers.
Is C17460-TH04 easy to machine?
Reasonably — machinability is rated fair (45/100, better than 64% of copper alloy grades). Machines like a hard bronze — carbide tooling, positive rake, flood coolant; wet-cut and capture fines/dust because of beryllium content (OSHA/ACGIH exposure controls).
Can C17460-TH04 be welded?
With care — weldability is rated fair (45/100). Resistance and electron-beam welding good; GTAW possible with matching filler but the heat-affected zone loses age-hardened strength and normally needs re-solutioning and re-aging.
What surface finishes work on C17460-TH04?
Not anodizable; electroplate Ni barrier plus Sn, Ag or Au for contacts, or passivate/lacquer to limit tarnish; polishes to a bright finish.
Can C17460-TH04 be formed, bent or molded?
Form in TB00/TD04 then age (600–800 °F class cycle, roughly 3 h at ~480 °C) for peak properties; mill-hardened TM tempers are formed as delivered with grain-direction bend limits.
What is the maximum service temperature of C17460-TH04?
C17460-TH04 is rated for continuous use to about 320°C (608 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between C17460-TF00 and C17460-TB00?
TF00 is the default condition — standard stocked rod/bar condition: peak-aged for balanced 700–830 MPa strength with ~50% IACS conductivity. TB00: softest condition for deep forming, stamping or machining before customer age hardening. Yield strength is 620 MPa in TF00 versus 170 MPa in TB00.
Sources
- ASTM B441 — Copper-Cobalt-Beryllium and Copper-Nickel-Beryllium Rod and Bar — ASTM International (2021)
- ASTM B534 — Copper-Cobalt-Beryllium / Copper-Nickel-Beryllium Plate, Sheet, Strip and Rolled Bar — ASTM International (2018)
- Alloy 174 (C17460) high-conductivity beryllium copper data — Materion Brush Performance Alloys (2021)
- UNS C17460 alloy datasheet — Copper Development Association (copper.org) (2023)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
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.