Copper Alloy C91000-M05
Finish state
UNS C91000
M05 = as plaster cast
Near-net-shape small intricate wear parts where machining of the hard δ-phase is to be minimised.
Values for the M05 condition
Other C91000 tempers and conditions
C91000 is listed in 6 conditions; see the grade overview at C91000.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Heat treated | Optional low-temperature soak to relieve casting stresses and even out coring; slightly lowers hardness, improves dimensional stability. | 145 | 220 | 2 | 125 HB | 10 % IACS |
M01Default As sand cast | Standard foundry condition for bushings, worm gears and wear plates; most widely stocked/produced form. | 150 | 225 | 1.5 | 135 HB | 9 % IACS |
M05This page As plaster cast | Near-net-shape small intricate wear parts where machining of the hard δ-phase is to be minimised. | 150 | 225 | 1.5 | 135 HB | 9 % IACS |
As hot forged and air cooled | For repeat-production small parts needing tight dimensions and a chilled, harder wear surface. | 160 | 240 | 1.5 | 145 HB | 9 % IACS |
As centrifugally cast | Choose for dense, pore-free sleeves and rings; the finer chilled structure raises strength and hardness slightly. | 165 | 250 | 2 | 140 HB | 9 % IACS |
As investment cast | Continuous-cast bar/tube stock for machined bushings — most uniform, lowest porosity, best machined surface. | 175 | 265 | 3 | 130 HB | 9 % IACS |
What is C91000-M05?
C91000-M05 is C91000 supplied in the M05 condition — near-net-shape small intricate wear parts where machining of the hard δ-phase is to be minimised. C91000-M05 has a yield strength of 150 MPa (21.8 ksi) and a tensile strength of 225 MPa (32.6 ksi) — weaker than 69% of copper alloy grades. Elongation at break is 1.5% and the elastic modulus is 103 GPa (14.9 Msi). C91000-M05 has a density of 8.8 g/cm³ (0.318 lb/in³), heavier than 58% of copper alloy grades. It melts at 830°C (1,526 °F). M01 is the default condition FabDigit quotes; M05 is available on request or by drawing note.
Limitations
- Limited ductility — 1.5%, worse than 98% of copper alloy grades
- Limited formability — 5/100, worse than 98% of copper alloy grades
- Difficult to weld — 15/100, worse than 94% of copper alloy grades
- High embodied carbon — 4.6 kg CO₂/kg, worse than 82% of copper alloy grades
- Low electrical conductivity — 9 % IACS, worse than 78% of copper alloy grades
C91000-M05 properties
Typical room-temperature values for C91000-M05; 21 are specific to this condition. Other listed values are C91000 reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
C91000-M05 has a density of 8.8 g/cm³ (0.318 lb/in³), heavier than 58% of copper alloy grades. It melts at 830°C (1,526 °F).
Mechanical15
C91000-M05 has a yield strength of 150 MPa (21.8 ksi) and a tensile strength of 225 MPa (32.6 ksi) — weaker than 69% of copper alloy grades. Elongation at break is 1.5% and the elastic modulus is 103 GPa (14.9 Msi).
Thermal6
C91000-M05 is rated for continuous service to 250°C (482 °F). It conducts heat at 47 W/m·K (27.2 BTU/hr·ft·°F), worse than 69% of copper alloy grades. Thermal expansion is 18 µm/m·K (10 µin/in·°F).
Electrical3
C91000-M05 conducts electricity at 9 % IACS, worse than 78% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (65/100), better than 58% of copper alloy grades.
Sustainability4
Producing a kilogram of C91000-M05 takes about 62 MJ of energy and emits 4.6 kg of CO₂ — more than 76% of copper alloy grades. Typical recycled content is 40%.
Manufacturability8
C91000-M05's machinability is poor (30/100, worse than 67% of copper alloy grades); weldability poor (15/100); formability not recommended (5/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with C91000-M05
Is C91000 easy to machine?
Machines like a hard, brittle bronze — short chips, use sharp positive-rake carbide, moderate speed and rigid setup; the δ phase is abrasive and dulls HSS quickly.
Can C91000 be welded?
Fusion welding is not recommended (hot-short, cracks readily); repair by brazing or soft soldering, or replace the casting.
Can C91000 be formed, bent or molded?
Cast only — no hot or cold working; pour with adequate risering and chills to limit inverse segregation, gas porosity and shrinkage in the wide freezing range.
What surface finishes work on C91000?
Takes a fine ground/lapped bearing surface and can be polished or chemically patinated; electroplating (Ni, Sn) is possible but rarely needed.
C91000 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 |
|---|---|---|
| CuCu + named elements ≥ 99.4 % | 84 – 86 | 85 |
| Snforms hard δ (Cu31Sn8) phase | 14 – 16 | 15 |
| Zn | ≤ 1.5 | — |
| Pb | ≤ 0.2 | — |
| Nicounted with Co in some listings | ≤ 0.8 | — |
| Fe | ≤ 0.2 | — |
| Sb | ≤ 0.2 | — |
| P | ≤ 0.05 | — |
| S | ≤ 0.05 | — |
| Al | ≤ 0.01 | — |
| Si | ≤ 0.01 | — |
C91000-M05 — frequently asked
What is C91000-M05 used for?
C91000-M05 is typically used for worm gears, wear rings and sliding parts. In short: hardest common tin bronze; low-speed wear parts; brittle, shock-sensitive casting.
What is the yield strength of C91000-M05?
C91000-M05 has a typical yield strength of 150 MPa (21.8 ksi) and a tensile strength of 225 MPa (32.6 ksi) — weaker than 69% of copper alloy grades. Strength varies by condition: see the 6 listed tempers.
Is C91000-M05 easy to machine?
Not especially — machinability is rated poor (30/100, worse than 67% of copper alloy grades). Machines like a hard, brittle bronze — short chips, use sharp positive-rake carbide, moderate speed and rigid setup; the δ phase is abrasive and dulls HSS quickly.
Can C91000-M05 be welded?
Not readily — weldability is rated poor (15/100). Fusion welding is not recommended (hot-short, cracks readily); repair by brazing or soft soldering, or replace the casting.
What surface finishes work on C91000-M05?
Takes a fine ground/lapped bearing surface and can be polished or chemically patinated; electroplating (Ni, Sn) is possible but rarely needed.
Can C91000-M05 be formed, bent or molded?
Cast only — no hot or cold working; pour with adequate risering and chills to limit inverse segregation, gas porosity and shrinkage in the wide freezing range.
What is the maximum service temperature of C91000-M05?
C91000-M05 is rated for continuous use to about 250°C (482 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between C91000-M01 and C91000-M06?
M01 is the default condition — standard foundry condition for bushings, worm gears and wear plates; most widely stocked/produced form. M06: continuous-cast bar/tube stock for machined bushings — most uniform, lowest porosity, best machined surface. Yield strength is 150 MPa in M01 versus 175 MPa in M06.
Sources
- Copper Alloy C91000 alloy data sheet — Copper Development Association (copper.org) (2023)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials (cast tin bronzes) — ASM International (1990)
- ASTM B505/B505M — Copper Alloy Continuous Castings — ASTM International (2018)
- ASTM B22 — Bronze Castings for Bridges and Turntables — ASTM International (2017)
- ASM Handbook Vol. 13B — Corrosion of copper and copper alloys — ASM International (2005)
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.