Precious Metal BAu-2
UNS P00800
BAu-2 (P00800) is an 80% Au-20% Cu braze filler in the BAu family, higher in gold than BAu-1 and correspondingly more oxidation resistant.
Reference datasheet — BAu-2 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the ANN condition
BAu-2 tempers and conditions
BAu-2 is supplied in 3 conditions, soft to hard. ANN is the default FabDigit quotes; the values on this page are for it.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
As built (as printed) | Use these values to assess the real joint: the seam solidifies as a fine-grained cast structure at 340 MPa tensile and 400 °C maximum service, sensitive to gap and base-metal diffusion. | 180 | 340 | 20 | 143 HB | 14 % IACS |
ANNDefault Annealed | Pick this soft wire, ribbon or stamped preform ring, the usual supply state, for easy assembly and automatic feeding; 30% elongation and 14% IACS come with only 200 MPa yield. | 200 | 380 | 30 | 138 HB | 14 % IACS |
Hardened | Choose the as-drawn or cold-rolled, unannealed wire and strip when stiffness aids precise shearing of small preforms; 620 MPa tensile comes with 4% elongation and poor bend formability. | 500 | 620 | 4 | 17 HRC | 13 % IACS |
Supply forms, finishes and certifications
Ways BAu-2 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
PWD | Powder / Paste | Supply form |
What is BAu-2?
BAu-2 (P00800) is an 80% Au-20% Cu braze filler in the BAu family, higher in gold than BAu-1 and correspondingly more oxidation resistant. Annealed stock gives about 200 MPa yield, 380 MPa tensile, 30% elongation and 14% IACS conductivity, and is supplied as wire, hard-drawn strip, stamped preforms and powder for hermetic packages, aerospace assemblies, nuclear components and high-vacuum equipment. The high gold content makes it the costliest option in the family, and it still requires a clean vacuum or reducing-atmosphere furnace cycle; BAu-1 is the lower-cost alternative. BAu-2 has a density of 15.9 g/cm³ (0.574 lb/in³), heavier than 81% of precious metal grades. It melts at 889°C (1,632 °F). BAu-2 has a yield strength of 200 MPa (29 ksi) and a tensile strength of 380 MPa (55.1 ksi) — stronger than 51% of precious metal grades. Elongation at break is 30% and the elastic modulus is 90 GPa (13.1 Msi).
What is BAu-2 used for?
- Hermetic electronic packages
- Aerospace brazed assemblies
- Nuclear component joining
- High-vacuum equipment
Advantages
- Good corrosion resistance — 95/100, better than 82% of precious metal grades
Limitations
- High embodied carbon — 15,000 kg CO₂/kg, worse than 94% of precious metal grades
- Heavy — 15.9 g/cm³ (0.574 lb/in³), worse than 81% of precious metal grades
- Poor heat conductor — 50 W/m·K (28.9 BTU/hr·ft·°F), worse than 79% of precious metal grades
BAu-2 properties
Typical room-temperature values for BAu-2-ANN; bars are the position among precious metal grades.
Physical3
BAu-2 has a density of 15.9 g/cm³ (0.574 lb/in³), heavier than 81% of precious metal grades. It melts at 889°C (1,632 °F).
Mechanical13
BAu-2 has a yield strength of 200 MPa (29 ksi) and a tensile strength of 380 MPa (55.1 ksi) — stronger than 51% of precious metal grades. Elongation at break is 30% and the elastic modulus is 90 GPa (13.1 Msi).
Thermal6
BAu-2 is rated for continuous service to 400°C (752 °F). It conducts heat at 50 W/m·K (28.9 BTU/hr·ft·°F), worse than 79% of precious metal grades. Thermal expansion is 15.5 µm/m·K (8.61 µin/in·°F).
Electrical3
BAu-2 conducts electricity at 14 % IACS, worse than 70% of precious metal grades.
Chemical & Environmental3
Corrosion resistance is excellent (95/100), better than 82% of precious metal grades.
Sustainability4
Producing a kilogram of BAu-2 takes about 210,000 MJ of energy and emits 15,000 kg of CO₂ — more than 88% of precious metal grades. Typical recycled content is 85%.
Manufacturability7
BAu-2's machinability is fair (35/100, worse than 73% of precious metal grades); weldability good (55/100); formability excellent (85/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the precious metal family
Yield strength against density for every precious metal grade FabDigit runs. BAu-2 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with BAu-2
Is BAu-2 easy to machine?
Extremely gummy; use sharp, high positive rake carbide tools with small depths of cut. All chips must be collected separately for precious-metal recovery.
Can BAu-2 be welded?
Used as a braze filler; it is not fusion welded. Joint cleanliness and a vacuum or hydrogen reducing atmosphere matter more than any welding parameter.
Can BAu-2 be formed, bent or molded?
Very ductile in the annealed temper (formability score 85): draws to fine wire, rolls to foil and stamps into preform rings. Intermediate anneal at 600-700 °C after cold work.
BAu-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. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| AuAWS A5.8 BAu-2 / UNS P00800 | 79.5 – 80.5 | 80 |
| Other (total)upper limit on total impurities | ≤ 0.15 | |
| Cu | balance |
What surface finishes work on BAu-2?
The gold fillet resists oxidation as brazed and can be ultrasonically cleaned directly. No plating is needed; light polishing is optional, and chlorinated cleaners should be avoided.
Equivalent designations
Standards and trade names that resolve to Precious Metal BAu-2 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- P00800
- Also called
- AWS BAu-2
How much does BAu-2 cost?
BAu-2 is a high-cost precious metal ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
BAu-2 — frequently asked
What is BAu-2 used for?
BAu-2 is typically used for hermetic electronic packages, aerospace brazed assemblies, nuclear component joining and high-vacuum equipment. In short: most oxidation-resistant BAu filler; very ductile brazed joints; highest gold cost.
What is the yield strength of BAu-2?
BAu-2 has a typical yield strength of 200 MPa (29 ksi) and a tensile strength of 380 MPa (55.1 ksi) — stronger than 51% of precious metal grades. Strength varies by condition: see the 3 listed tempers.
Is BAu-2 easy to machine?
Not especially — machinability is rated fair (35/100, worse than 73% of precious metal grades). Extremely gummy; use sharp, high positive rake carbide tools with small depths of cut. All chips must be collected separately for precious-metal recovery.
Can BAu-2 be welded?
Yes — weldability is rated good (55/100). Used as a braze filler; it is not fusion welded. Joint cleanliness and a vacuum or hydrogen reducing atmosphere matter more than any welding parameter.
What surface finishes work on BAu-2?
The gold fillet resists oxidation as brazed and can be ultrasonically cleaned directly. No plating is needed; light polishing is optional, and chlorinated cleaners should be avoided.
Can BAu-2 be formed, bent or molded?
Very ductile in the annealed temper (formability score 85): draws to fine wire, rolls to foil and stamps into preform rings. Intermediate anneal at 600-700 °C after cold work.
What is the maximum service temperature of BAu-2?
BAu-2 is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between BAu-2-ANN and BAu-2-H?
ANN is the default condition — pick this soft wire, ribbon or stamped preform ring, the usual supply state, for easy assembly and automatic feeding; 30% elongation and 14% IACS come with only 200 MPa yield. H: choose the as-drawn or cold-rolled, unannealed wire and strip when stiffness aids precise shearing of small preforms; 620 MPa tensile comes with 4% elongation and poor bend formability. Yield strength is 200 MPa in ANN versus 500 MPa in H.
How much does BAu-2 cost?
BAu-2 is a high-cost precious metal ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- AWS A5.8/A5.8M — Specification for Filler Metals for Brazing and Braze Welding — AWS (2019)
- ASM Handbook Vol.6 — Welding, Brazing and Soldering (Brazing Filler Metals) — ASM International (1993)
- ASM Handbook Vol.2 — Properties of Precious Metals and Alloys — ASM International (1990)
- Gold-copper brazing alloy (80Au-20Cu) technical data (2023)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.