Copper Alloy C99600-HT (Heat treated)
Heat-treated state
UNS C99600
Choose when higher strength and hardness are needed for gears, wear plates and heavily loaded structural castings, accepting some loss of damping and ductility.
Values for the HT condition
Other C99600 tempers and conditions
C99600 is listed in 2 conditions; see the grade overview at C99600.
- F
- HT
Compare all 2 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
FDefault As fabricated | Standard stocked condition: best vibration-damping capacity with moderate strength — pick for noise/vibration-control housings, bedplates and marine parts. | 193 | 434 | 20 | 115 HB | 2.5 % IACS |
HTThis page Heat treated | Choose when higher strength and hardness are needed for gears, wear plates and heavily loaded structural castings, accepting some loss of damping and ductility. | 275 | 550 | 12 | 180 HB | 2.4 % IACS |
What is C99600-HT?
C99600-HT is C99600 heat treated to HT — choose when higher strength and hardness are needed for gears, wear plates and heavily loaded structural castings, accepting some loss of damping and ductility. C99600-HT has a yield strength of 275 MPa (39.9 ksi) and a tensile strength of 550 MPa (79.8 ksi) — stronger than 57% of copper alloy grades. Elongation at break is 12% and the elastic modulus is 103 GPa (14.9 Msi). C99600-HT has a density of 7.5 g/cm³ (0.271 lb/in³), lighter than 98% of copper alloy grades. It melts at 900°C (1,652 °F). F is the default condition FabDigit quotes; HT is available on request or by drawing note.
Advantages
- Lightweight — 7.5 g/cm³ (0.271 lb/in³), better than 98% of copper alloy grades
Limitations
- Low electrical conductivity — 2.4 % IACS, worse than 100% of copper alloy grades
- Poor heat conductor — 23 W/m·K (13.3 BTU/hr·ft·°F), worse than 99% of copper alloy grades
- Hard to polish — 55/100, worse than 97% of copper alloy grades
- Needs corrosion protection — 50/100, worse than 95% of copper alloy grades
- Difficult to machine — 25/100, worse than 86% of copper alloy grades
C99600-HT properties
Typical room-temperature values for C99600-HT; 16 are specific to this condition. Other listed values are C99600 reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
C99600-HT has a density of 7.5 g/cm³ (0.271 lb/in³), lighter than 98% of copper alloy grades. It melts at 900°C (1,652 °F).
Mechanical13
C99600-HT has a yield strength of 275 MPa (39.9 ksi) and a tensile strength of 550 MPa (79.8 ksi) — stronger than 57% of copper alloy grades. Elongation at break is 12% and the elastic modulus is 103 GPa (14.9 Msi).
Thermal6
C99600-HT is rated for continuous service to 230°C (446 °F). It conducts heat at 23 W/m·K (13.3 BTU/hr·ft·°F), worse than 99% of copper alloy grades. Thermal expansion is 18.5 µm/m·K (10.3 µin/in·°F).
Electrical3
C99600-HT conducts electricity at 2.4 % IACS, worse than 100% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is fair (50/100), worse than 95% of copper alloy grades.
Sustainability4
Producing a kilogram of C99600-HT takes about 60 MJ of energy and emits 4.5 kg of CO₂ — more than 69% of copper alloy grades. Typical recycled content is 40%.
Manufacturability8
C99600-HT's machinability is poor (25/100, worse than 86% of copper alloy grades); weldability fair (40/100); formability poor (25/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with C99600-HT
Is C99600 easy to machine?
Tough, work-hardening Cu-Mn matrix: use sharp positive-rake carbide, low speed (60–110 m/min), heavy feed and flood coolant to avoid built-up edge and smearing.
Can C99600 be welded?
GTAW/GMAW with matching Cu-Mn-Al filler under argon; keep interpass temperature low, avoid dilution with steel and stress-relieve to restore damping.
Can C99600 be formed, bent or molded?
Supplied as sand or centrifugal castings — degas and control Mn oxidation loss with covering flux; generous fillets and controlled solidification prevent hot tearing; cold forming is not practical.
What surface finishes work on C99600?
Not anodizable; use epoxy/marine paint, nickel plating or chemical conversion for corrosion protection — bare surfaces darken and can dealloy in seawater.
C99600 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 |
|---|---|---|
| Mnprovides the antiferromagnetic, high-damping matrix | 39 – 45 | 42 |
| Alstrengthener / deoxidiser | 1 – 2.8 | 2 |
| Feimpurity limit | ≤ 0.25 | 0.1 |
| Curemainder, nominally ~54–58 % | balance | — |
C99600-HT — frequently asked
What is C99600-HT used for?
C99600-HT is typically used for gears, wear plates and heavy-duty structural castings. In short: high-strength cast Cu-Mn; wear-resistant gear bronze; heat-treatable cast copper.
What is the yield strength of C99600-HT?
C99600-HT has a typical yield strength of 275 MPa (39.9 ksi) and a tensile strength of 550 MPa (79.8 ksi) — stronger than 57% of copper alloy grades. Strength varies by condition: see the 2 listed tempers.
Is C99600-HT easy to machine?
Not especially — machinability is rated poor (25/100, worse than 86% of copper alloy grades). Tough, work-hardening Cu-Mn matrix: use sharp positive-rake carbide, low speed (60–110 m/min), heavy feed and flood coolant to avoid built-up edge and smearing.
Can C99600-HT be welded?
With care — weldability is rated fair (40/100). GTAW/GMAW with matching Cu-Mn-Al filler under argon; keep interpass temperature low, avoid dilution with steel and stress-relieve to restore damping.
What surface finishes work on C99600-HT?
Not anodizable; use epoxy/marine paint, nickel plating or chemical conversion for corrosion protection — bare surfaces darken and can dealloy in seawater.
Can C99600-HT be formed, bent or molded?
Supplied as sand or centrifugal castings — degas and control Mn oxidation loss with covering flux; generous fillets and controlled solidification prevent hot tearing; cold forming is not practical.
What is the maximum service temperature of C99600-HT?
C99600-HT is rated for continuous use to about 230°C (446 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between C99600-F and C99600-HT?
F is the default condition — standard stocked condition: best vibration-damping capacity with moderate strength — pick for noise/vibration-control housings, bedplates and marine parts. HT: choose when higher strength and hardness are needed for gears, wear plates and heavily loaded structural castings, accepting some loss of damping and ductility. Yield strength is 193 MPa in F versus 275 MPa in HT.
Sources
- Copper Alloy C99600 alloy data (UNS registration, special cast copper alloys) — Copper Development Association (copper.org) (2023)
- ASTM B505/B505M — Copper Alloy Continuous Castings — ASTM International (2018)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials — ASM International (1990)
- ASM Handbook Vol. 3 — Alloy Phase Diagrams (Cu-Mn system) — ASM International (1992)
- High-damping manganese-copper alloys (INCRA project reports) — International Copper Research Association (1980)
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.