Precious Metal BVAg-6b AS-BRAZED
Heat-treated state
UNS P07507
Reference condition for joint design values on steel/stainless lap joints.
Values for the AS-BRAZED condition
What is BVAg-6b AS-BRAZED?
BVAg-6b AS-BRAZED is BVAg-6b heat treated to AS-BRAZED — reference condition for joint design values on steel/stainless lap joints. BVAg-6b AS-BRAZED has a yield strength of 150 MPa (21.8 ksi) and a tensile strength of 320 MPa (46.4 ksi) — weaker than 68% of precious metal grades. Elongation at break is 20% and the elastic modulus is 100 GPa (14.5 Msi). BVAg-6b AS-BRAZED has a density of 9.6 g/cm³ (0.347 lb/in³), lighter than 80% of precious metal grades. It melts at 779°C (1,434 °F).
Advantages
- Low embodied carbon — 57 kg CO₂/kg, better than 83% of precious metal grades
Limitations
- Needs corrosion protection — 55/100, worse than 94% of precious metal grades
- Difficult to weld — 20/100, worse than 86% of precious metal grades
- Limited ductility — 20%, worse than 77% of precious metal grades
BVAg-6b AS-BRAZED properties
Typical room-temperature values for BVAg-6b AS-BRAZED; 5 are specific to this condition. Other listed values are BVAg-6b reference data and may not represent this condition. Bars are the position among precious metal grades.
Physical3
BVAg-6b AS-BRAZED has a density of 9.6 g/cm³ (0.347 lb/in³), lighter than 80% of precious metal grades. It melts at 779°C (1,434 °F).
Mechanical10
BVAg-6b AS-BRAZED has a yield strength of 150 MPa (21.8 ksi) and a tensile strength of 320 MPa (46.4 ksi) — weaker than 68% of precious metal grades. Elongation at break is 20% and the elastic modulus is 100 GPa (14.5 Msi).
Thermal6
BVAg-6b AS-BRAZED is rated for continuous service to 370°C (698 °F). It conducts heat at 220 W/m·K (127.1 BTU/hr·ft·°F), better than 72% of precious metal grades. Thermal expansion is 18.2 µm/m·K (10.1 µin/in·°F).
Electrical3
BVAg-6b AS-BRAZED conducts electricity at 48 % IACS, better than 70% of precious metal grades.
Chemical & Environmental3
Corrosion resistance is good (55/100), worse than 94% of precious metal grades.
Sustainability4
Producing a kilogram of BVAg-6b AS-BRAZED takes about 800 MJ of energy and emits 57 kg of CO₂ — less than 83% of precious metal grades. Typical recycled content is 60%.
Manufacturability6
BVAg-6b AS-BRAZED's machinability is fair (35/100, worse than 73% of precious metal grades); weldability poor (20/100); formability very good (80/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with BVAg-6b AS-BRAZED
Is BVAg-6b easy to machine?
Rarely machined; the alloy is soft and gummy — use sharp, high-rake tools, generous lubricant and take scrap back to the refiner.
Can BVAg-6b be welded?
Not a base metal for fusion welding; it is the filler — braze at 850–900 °C in vacuum (10⁻⁴ mbar or better) or dry hydrogen, or with a torch and white flux in air.
Can BVAg-6b be formed, bent or molded?
Excellent cold formability when annealed — drawn to fine wire, rolled to foil and stamped into rings; interanneal around 600–650 °C in a protective atmosphere.
What surface finishes work on BVAg-6b?
Fillets can be bright-dipped or polished to a silver finish; passivate or lacquer if sulphur tarnishing of exposed joints is a concern, and avoid nitric-acid pickles that dissolve the filler.
BVAg-6b 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 |
|---|---|---|
| Ag | 49 – 51 | 50 |
| Znrestricted for low vapour pressure | ≤ 0 | |
| Cdrestricted for low vapour pressure | ≤ 0 | |
| P | ≤ 0 | |
| Pb | ≤ 0 | |
| other elements totalAWS A5.8 vacuum-grade impurity limit | ≤ 0.15 | |
| Cu | ≥ 48.5 (balance) |
BVAg-6b AS-BRAZED — frequently asked
What is BVAg-6b AS-BRAZED used for?
BVAg-6b AS-BRAZED is typically used for vacuum furnace brazing of stainless steel assemblies, copper alloy vacuum joints, stainless-to-copper tube and fitting transitions, ring and washer preforms for tube joints, vacuum chamber fittings and flange subassemblies and torch-brazed copper alloy plumbing in air with white flux. In short: vacuum-grade 50Ag filler; controlled zinc outgassing; wide-gap brazing filler.
What is the yield strength of BVAg-6b AS-BRAZED?
BVAg-6b AS-BRAZED has a typical yield strength of 150 MPa (21.8 ksi) and a tensile strength of 320 MPa (46.4 ksi) — weaker than 68% of precious metal grades.
Is BVAg-6b AS-BRAZED easy to machine?
Not especially — machinability is rated fair (35/100, worse than 73% of precious metal grades). Rarely machined; the alloy is soft and gummy — use sharp, high-rake tools, generous lubricant and take scrap back to the refiner.
Can BVAg-6b AS-BRAZED be welded?
Not readily — weldability is rated poor (20/100). Not a base metal for fusion welding; it is the filler — braze at 850–900 °C in vacuum (10⁻⁴ mbar or better) or dry hydrogen, or with a torch and white flux in air.
What surface finishes work on BVAg-6b AS-BRAZED?
Fillets can be bright-dipped or polished to a silver finish; passivate or lacquer if sulphur tarnishing of exposed joints is a concern, and avoid nitric-acid pickles that dissolve the filler.
Can BVAg-6b AS-BRAZED be formed, bent or molded?
Excellent cold formability when annealed — drawn to fine wire, rolled to foil and stamped into rings; interanneal around 600–650 °C in a protective atmosphere.
What is the maximum service temperature of BVAg-6b AS-BRAZED?
BVAg-6b AS-BRAZED is rated for continuous use to about 370°C (698 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- AWS A5.8M/A5.8 Specification for Filler Metals for Brazing and Braze Welding (vacuum-grade BVAg classifications) — American Welding Society (2019)
- ASM Handbook Vol. 6 — Welding, Brazing and Soldering (silver brazing filler metals) — ASM International (1993)
- ASM Handbook Vol. 2 — Properties of Nonferrous Alloys (Ag, Cu, Ag-Cu system) — ASM International (1990)
- Vacuum-grade silver brazing alloy data (Ag-Cu 50/50) — Lucas-Milhaupt / Morgan Advanced Materials (Wesgo Metals) (2023)
- GB/T 10046 — SAC / (2018)
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.