Copper Alloy BCu-2 AS-BRAZED
Heat-treated state · default condition
UNS C81100 · GB BCu100
Default condition: the essentially pure copper metal left in the joint after the oxide paste is reduced at 1090–1150 °C in hydrogen or dissociated ammonia.
Values for the AS-BRAZED condition
Other BCu-2 tempers and conditions
BCu-2 is listed in 2 conditions; see the grade overview at BCu-2.
- Cast
- AS-BRAZED
Compare all 2 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
As cast | Reference condition used when the deposit is evaluated as bulk cast copper (test castings, filler slugs). | 62 | 172 | 40 | 44 HB | 92 % IACS |
AS-BRAZEDDefaultThis page reduced copper joint/deposit after furnace brazing | Default condition: the essentially pure copper metal left in the joint after the oxide paste is reduced at 1090–1150 °C in hydrogen or dissociated ammonia. | 65 | 200 | 35 | 45 HB | 90 % IACS |
What is BCu-2 AS-BRAZED?
BCu-2 AS-BRAZED is BCu-2 heat treated to AS-BRAZED — default condition: the essentially pure copper metal left in the joint after the oxide paste is reduced at 1090–1150 °C in hydrogen or dissociated ammonia. BCu-2 AS-BRAZED has a yield strength of 65 MPa (9.43 ksi) and a tensile strength of 200 MPa (29 ksi) — weaker than 98% of copper alloy grades. Elongation at break is 35% and the elastic modulus is 115 GPa (16.7 Msi). BCu-2 AS-BRAZED has a density of 8.92 g/cm³ (0.322 lb/in³), heavier than 81% of copper alloy grades. It melts at 1,083°C (1,981 °F).
Advantages
- Tough — resists crack growth — 90 MPa·√m (81.9 ksi·√in), better than 96% of copper alloy grades
- High service temperature — 350°C (662 °F), better than 95% of copper alloy grades
- Forms and bends easily — 90/100, better than 89% of copper alloy grades
- Conducts heat well — 346 W/m·K (199.9 BTU/hr·ft·°F), better than 87% of copper alloy grades
- High electrical conductivity — 90 % IACS, better than 87% of copper alloy grades
Limitations
- Low strength — 65 MPa (9.43 ksi), worse than 98% of copper alloy grades
- Difficult to machine — 25/100, worse than 86% of copper alloy grades
BCu-2 AS-BRAZED properties
Typical room-temperature values for BCu-2 AS-BRAZED; 21 are specific to this condition. Other listed values are BCu-2 reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
BCu-2 AS-BRAZED has a density of 8.92 g/cm³ (0.322 lb/in³), heavier than 81% of copper alloy grades. It melts at 1,083°C (1,981 °F).
Mechanical15
BCu-2 AS-BRAZED has a yield strength of 65 MPa (9.43 ksi) and a tensile strength of 200 MPa (29 ksi) — weaker than 98% of copper alloy grades. Elongation at break is 35% and the elastic modulus is 115 GPa (16.7 Msi).
Thermal6
BCu-2 AS-BRAZED is rated for continuous service to 350°C (662 °F). It conducts heat at 346 W/m·K (199.9 BTU/hr·ft·°F), better than 87% of copper alloy grades. Thermal expansion is 17.6 µm/m·K (9.78 µin/in·°F).
Electrical3
BCu-2 AS-BRAZED conducts electricity at 90 % IACS, better than 87% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (58/100), worse than 76% of copper alloy grades.
Sustainability4
Producing a kilogram of BCu-2 AS-BRAZED takes about 50 MJ of energy and emits 3.8 kg of CO₂ — less than 89% of copper alloy grades. Typical recycled content is 30%.
Manufacturability8
BCu-2 AS-BRAZED's machinability is poor (25/100, worse than 86% of copper alloy grades); weldability fair (45/100); formability excellent (90/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with BCu-2 AS-BRAZED
Is BCu-2 easy to machine?
Deposit is soft, gummy pure copper — use sharp positive-rake tools, high speed, generous coolant; expect burrs and poor chip breaking.
Can BCu-2 be welded?
Not a structural weld metal; joints are made by furnace/torch brazing at 1090–1150 °C, and re-heating a BCu joint above ~1080 °C will remelt it.
Can BCu-2 be formed, bent or molded?
Supplied as paste or powder — dispense, screen-print or press into preforms; joint clearances of 0.00–0.05 mm (interference to line-to-line) give the best capillary fill.
What surface finishes work on BCu-2?
Bright reduced-copper fillets tarnish in air; protect with lacquer, or nickel/tin plate. Copper is not anodizable.
BCu-2 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.
| Element | Spec limit (wt %) |
|---|---|
| P | ≤ 0.08 |
| Pb | ≤ 0.02 |
| Other (total)Residuals excluding the organic vehicle and combined oxygen | ≤ 0.5 |
| CuMetallic copper content of the supplied oxide/vehicle product per AWS A5.8; the reduced deposit is essentially pure Cu | ≥ 86.5 (balance) |
BCu-2 AS-BRAZED — frequently asked
What is BCu-2 AS-BRAZED used for?
BCu-2 AS-BRAZED is typically used for furnace brazing of steel joints, heat exchanger fin brazing, copper-to-steel joints and hydrogen-atmosphere brazing. In short: oxygen-free copper braze deposit; high-conductivity brazed joint; paste and powder forms.
What is the yield strength of BCu-2 AS-BRAZED?
BCu-2 AS-BRAZED has a typical yield strength of 65 MPa (9.43 ksi) and a tensile strength of 200 MPa (29 ksi) — weaker than 98% of copper alloy grades. Strength varies by condition: see the 2 listed tempers.
Is BCu-2 AS-BRAZED easy to machine?
Not especially — machinability is rated poor (25/100, worse than 86% of copper alloy grades). Deposit is soft, gummy pure copper — use sharp positive-rake tools, high speed, generous coolant; expect burrs and poor chip breaking.
Can BCu-2 AS-BRAZED be welded?
With care — weldability is rated fair (45/100). Not a structural weld metal; joints are made by furnace/torch brazing at 1090–1150 °C, and re-heating a BCu joint above ~1080 °C will remelt it.
What surface finishes work on BCu-2 AS-BRAZED?
Bright reduced-copper fillets tarnish in air; protect with lacquer, or nickel/tin plate. Copper is not anodizable.
Can BCu-2 AS-BRAZED be formed, bent or molded?
Supplied as paste or powder — dispense, screen-print or press into preforms; joint clearances of 0.00–0.05 mm (interference to line-to-line) give the best capillary fill.
What is the maximum service temperature of BCu-2 AS-BRAZED?
BCu-2 AS-BRAZED is rated for continuous use to about 350°C (662 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between BCu-2 AS-BRAZED and BCu-2 Cast?
AS-BRAZED is the default condition — default condition: the essentially pure copper metal left in the joint after the oxide paste is reduced at 1090–1150 °C in hydrogen or dissociated ammonia. Cast: reference condition used when the deposit is evaluated as bulk cast copper (test castings, filler slugs). Yield strength is 65 MPa in AS-BRAZED versus 62 MPa in Cast.
Sources
- AWS A5.8/A5.8M — Specification for Filler Metals for Brazing and Braze Welding — American Welding Society (2019)
- GB/T 6418 — SAC (2008)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- ASM Handbook Vol. 6 — Welding, Brazing and Soldering (brazing filler metals) — ASM International (1993)
- CDA alloy datasheet C81100 (cast pure copper) — Copper Development Association (2023)
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.