Precious Metal BVAu-6
UNS P00707
BVAu-6 is the vacuum grade of BAu-6, a high-gold brazing filler (nominally about 70% Au with Ag–Cu balance, UNS P00707) held to minimal vapor-pressure impurities for hermetic vacuum joints.
Reference datasheet — BVAu-6 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 AS-BRAZED condition
BVAu-6 tempers and conditions
BVAu-6 is supplied in one standard condition, AS-BRAZED. AS-BRAZED is the default FabDigit quotes; the values on this page are for it.
Supply forms, finishes and certifications
Ways BVAu-6 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
FOIL | Foil / Strip | Supply form |
POWDER-PASTE | Powder / Paste | Supply form |
PREFORM | Stamped washer / ring / disc from foil or wire | Supply form |
Wire-Ann | Wire / Rod | Supply form |
What is BVAu-6?
BVAu-6 is the vacuum grade of BAu-6, a high-gold brazing filler (nominally about 70% Au with Ag–Cu balance, UNS P00707) held to minimal vapor-pressure impurities for hermetic vacuum joints. It is used on hermetic electronic housings, traveling-wave tubes and semiconductor lids, and is supplied as annealed wire, foil, preforms, powder-paste and as-brazed stock. As-brazed strength is about 620 MPa tensile at 10% elongation, with service to 800 °C. The 1046–1120 °C braze cycle and the highest gold content in the series drive cost and base-metal selection; BVAu-3 or BVAu-5 are the lower-gold options. BVAu-6 has a density of 14.8 g/cm³ (0.535 lb/in³), heavier than 74% of precious metal grades. It melts at 1,005°C (1,841 °F). BVAu-6 has a tensile strength of 620 MPa (89.9 ksi), stronger than 96% of precious metal grades. Elongation at break is 10% and the elastic modulus is 130 GPa (18.9 Msi).
What is BVAu-6 used for?
- hermetic electronic housings
- traveling-wave tube assembly
- precision instrument brazing
- semiconductor die-attach lids
Advantages
- High service temperature — 800°C (1,472 °F), better than 90% of precious metal grades
- Stiff — 130 GPa (18.9 Msi), better than 83% of precious metal grades
- Good corrosion resistance — 95/100, better than 82% of precious metal grades
Limitations
- Low electrical conductivity — 5 % IACS, worse than 97% of precious metal grades
- Limited ductility — 10%, worse than 89% of precious metal grades
- Poor heat conductor — 35 W/m·K (20.2 BTU/hr·ft·°F), worse than 89% of precious metal grades
- Limited formability — 70/100, worse than 78% of precious metal grades
- High embodied carbon — 12,000 kg CO₂/kg, worse than 76% of precious metal grades
BVAu-6 properties
Typical room-temperature values for BVAu-6-AS-BRAZED; bars are the position among precious metal grades.
Physical3
BVAu-6 has a density of 14.8 g/cm³ (0.535 lb/in³), heavier than 74% of precious metal grades. It melts at 1,005°C (1,841 °F).
Mechanical6
BVAu-6 has a tensile strength of 620 MPa (89.9 ksi), stronger than 96% of precious metal grades. Elongation at break is 10% and the elastic modulus is 130 GPa (18.9 Msi).
Thermal5
BVAu-6 is rated for continuous service to 800°C (1,472 °F). It conducts heat at 35 W/m·K (20.2 BTU/hr·ft·°F), worse than 89% of precious metal grades. Thermal expansion is 15.5 µm/m·K (8.61 µin/in·°F).
Electrical3
BVAu-6 conducts electricity at 5 % IACS, worse than 97% of precious metal grades.
Chemical & Environmental3
Corrosion resistance is excellent (95/100), better than 82% of precious metal grades.
Sustainability3
Producing a kilogram of BVAu-6 takes about 190,000 MJ of energy and emits 12,000 kg of CO₂ — more than 81% of precious metal grades. Typical recycled content is 60%.
Manufacturability5
BVAu-6's formability very good (70/100).
Common Calculations4
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. BVAu-6 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with BVAu-6
Is BVAu-6 easy to machine?
Rarely machined; if a preform must be turned, use sharp carbide/diamond tooling, light cuts and full swarf capture for precious-metal recovery.
Can BVAu-6 be welded?
Not a structural weld filler — it is a brazing alloy; braze in vacuum (<10⁻⁴ mbar) or dry hydrogen at 1046–1120 °C with short time at temperature to limit Ni diffusion and base-metal erosion.
Can BVAu-6 be formed, bent or molded?
Ductile solid solution: cold rolls to <0.05 mm foil and draws to fine wire with intermediate anneals near 800–900 °C in protective atmosphere.
BVAu-6 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-6 / BVAu-6 | 69.5 – 70.5 | 70 |
| Pd | 7.5 – 8.5 | 8 |
| Cdvacuum-grade high-vapour-pressure limit | ≤ 0 | |
| Znvacuum-grade high-vapour-pressure limit | ≤ 0 | |
| Pvacuum-grade limit | ≤ 0 | |
| Other elements, totalimpurity ceiling | ≤ 0.15 | |
| Ni | ≥ 21 (balance) |
What surface finishes work on BVAu-6?
Joints need no plating or passivation; degrease only, since the fillet is tarnish-free and readily polished or ultrasonically cleaned.
Equivalent designations
Standards and trade names that resolve to Precious Metal BVAu-6 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- P00707
How much does BVAu-6 cost?
BVAu-6 is a high-cost precious metal ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
BVAu-6 — frequently asked
What is BVAu-6 used for?
BVAu-6 is typically used for hermetic electronic housings, traveling-wave tube assembly, precision instrument brazing and semiconductor die-attach lids. In short: highest gold content grade; strongest BVAu fillet; 800 °C service capability.
What is the tensile strength of BVAu-6?
BVAu-6 has a typical tensile strength of 620 MPa (89.9 ksi) — stronger than 96% of precious metal grades.
Is BVAu-6 easy to machine?
Rarely machined; if a preform must be turned, use sharp carbide/diamond tooling, light cuts and full swarf capture for precious-metal recovery.
Can BVAu-6 be welded?
Not a structural weld filler — it is a brazing alloy; braze in vacuum (<10⁻⁴ mbar) or dry hydrogen at 1046–1120 °C with short time at temperature to limit Ni diffusion and base-metal erosion.
What surface finishes work on BVAu-6?
Joints need no plating or passivation; degrease only, since the fillet is tarnish-free and readily polished or ultrasonically cleaned.
Can BVAu-6 be formed, bent or molded?
Ductile solid solution: cold rolls to <0.05 mm foil and draws to fine wire with intermediate anneals near 800–900 °C in protective atmosphere.
What is the maximum service temperature of BVAu-6?
BVAu-6 is rated for continuous use to about 800°C (1,472 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does BVAu-6 cost?
BVAu-6 is a high-cost precious metal ($$$$), 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 — American Welding Society (2019)
- ASM Handbook Vol.6 — Welding, Brazing and Soldering (Gold-base filler metals) — ASM International (1993)
- ASM Handbook Vol.2 — Properties of Nonferrous Alloys (Precious metals) — ASM International (1990)
- Vacuum-grade gold braze alloy datasheets (Au-Pd-Ni) — Morgan Advanced Materials / Wesgo Metals; Lucas-Milhaupt (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.