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Precious Metal BVAg-31 AS-BRAZED

Heat-treated state

UNS P07587

Design condition for joint strength calculations after a vacuum braze cycle at 870–925 °C.

High cost $$$$

Values for the AS-BRAZED condition

Other BVAg-31 tempers and conditions

BVAg-31 is listed in 2 conditions; see the grade overview at BVAg-31.

Compare all 2 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
AS-BRAZEDThis page
solidified filler in the joint
Design condition for joint strength calculations after a vacuum braze cycle at 870–925 °C.23040018115 HB10.5 % IACS
AnnealedDefault
vacuum-melted wire / rod, soft temper
Default stocked form: soft drawn wire or rod for hand feeding, automatic wire dispensing and ring forming.24042022110 HB11 % IACS

What is BVAg-31 AS-BRAZED?

BVAg-31 AS-BRAZED is BVAg-31 heat treated to AS-BRAZED — design condition for joint strength calculations after a vacuum braze cycle at 870–925 °C. BVAg-31 AS-BRAZED has a yield strength of 230 MPa (33.4 ksi) and a tensile strength of 400 MPa (58 ksi) — stronger than 70% of precious metal grades. Elongation at break is 18% and the elastic modulus is 100 GPa (14.5 Msi). BVAg-31 AS-BRAZED has a density of 10.1 g/cm³ (0.365 lb/in³), lighter than 61% of precious metal grades. It melts at 824°C (1,515 °F). Annealed is the default condition FabDigit quotes; AS-BRAZED is available on request or by drawing note.

Limitations

  • Limited formability — 55/100, worse than 89% of precious metal grades
  • Limited ductility — 18%, worse than 83% of precious metal grades
  • Low electrical conductivity — 10.5 % IACS, worse than 77% of precious metal grades

BVAg-31 AS-BRAZED properties

Typical room-temperature values for BVAg-31 AS-BRAZED; 18 are specific to this condition. Other listed values are BVAg-31 reference data and may not represent this condition. Bars are the position among precious metal grades.

Physical3

BVAg-31 AS-BRAZED has a density of 10.1 g/cm³ (0.365 lb/in³), lighter than 61% of precious metal grades. It melts at 824°C (1,515 °F).

Density10.1 g/cm³0.36 lb/in³
Melting Point (Solidus)824°C1,515 °F
Liquidus Temperature852°C1,566 °F

Mechanical13

BVAg-31 AS-BRAZED has a yield strength of 230 MPa (33.4 ksi) and a tensile strength of 400 MPa (58 ksi) — stronger than 70% of precious metal grades. Elongation at break is 18% and the elastic modulus is 100 GPa (14.5 Msi).

Elastic (Young's) Modulus100 GPa14.5 Msi
Shear Modulus37 GPa5.4 Msi
Bulk Modulus115 GPa16.7 Msi
Poisson's Ratio0.37
Tensile Strength (Ultimate)400 MPa58 ksi
Yield Strength (0.2% offset)230 MPa33.4 ksi
Elongation at Break18%
Reduction in Area25%
Shear Strength230 MPa33.4 ksi
Fatigue Strength (Endurance Limit)130 MPa18.9 ksi
Hardness, Brinell115 HB
Hardness, Rockwell B68 HRB
Hardness, Vickers120 HV

Thermal6

BVAg-31 AS-BRAZED is rated for continuous service to 450°C (842 °F). It conducts heat at 65 W/m·K (37.6 BTU/hr·ft·°F), worse than 67% of precious metal grades. Thermal expansion is 18 µm/m·K (10 µin/in·°F).

Thermal Conductivity65 W/m·K37.6 BTU/hr·ft·°F
Specific Heat Capacity260 J/kg·K0.06 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)18 µm/m·K10 µin/in·°F
Latent Heat of Fusion130 J/g55.9 BTU/lb
Max Service Temperature (continuous)450°C842 °F
Min Service Temperature-196°C-321 °F

Electrical3

BVAg-31 AS-BRAZED conducts electricity at 10.5 % IACS, worse than 77% of precious metal grades.

Electrical Conductivity10.5 % IACS
Electrical Resistivity1.65×10⁻⁷ Ω·m6.5 µΩ·in
Magnetic Responsenon-magnetic

Chemical & Environmental3

Corrosion resistance is very good (82/100), better than 53% of precious metal grades.

Galvanic Potential (seawater, vs SCE)0.05 V
Corrosion ResistanceVery good82/100
Chemical Resistance SummaryVery good resistance to humid air, tarnish and mild acids; palladium markedly improves sulphide/chloride tarnish resistance versus plain Ag-Cu. Attacked by nitric acid, hot sulphuric acid, ferric chloride and ammonia-bearing solutions (risk of stress corrosion in the copper-rich phase).

Sustainability3

Producing a kilogram of BVAg-31 AS-BRAZED takes about 4,400 MJ of energy and emits 420 kg of CO₂ — more than 58% of precious metal grades. Typical recycled content is 50%.

Embodied Energy (primary production)4,400 MJ/kg1,891,661 BTU/lb
Embodied Carbon (primary production)420 kg CO₂/kg
Typical Recycled Content50%

Manufacturability8

BVAg-31 AS-BRAZED's machinability is fair (40/100, worse than 60% of precious metal grades); weldability poor (30/100); formability good (55/100).

MachinabilityFair40/100
Machinability Rating (AISI 1212 = 100 %)35%
WeldabilityPoor30/100
Formability (cold)Good55/100
CastabilityVery good70/100
Brazeability / SolderabilityExcellent95/100
PolishabilityVery good80/100
Anodizing Responsen/a — not an anodizable alloy system (silver-palladium-copper)

Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.

Working with BVAg-31 AS-BRAZED

Is BVAg-31 easy to machine?

Rarely machined; the alloy is soft and gummy — use sharp, polished high-rake tools and collect all chips as precious-metal scrap.

Can BVAg-31 be welded?

Not a weld filler; joints are made by vacuum or dry-hydrogen furnace brazing at roughly 870–925 °C with a short soak to limit erosion of thin base metals.

Can BVAg-31 be formed, bent or molded?

Excellent cold formability in the annealed state — drawn to fine wire, rolled to 25 µm foil and stamped into rings; interstage anneal near 650–700 °C in inert atmosphere.

What surface finishes work on BVAg-31?

Fluxless brazing in vacuum leaves a bright, clean fillet needing no cleaning; if flux-brazed in air, remove residues with hot water/citric rinse before plating or passivation.

BVAg-31 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.

ElementSpec limit (wt %)Nominal
AgAWS A5.8 BVAg-31 / UNS P0758758 – 5958.5
Pdraises melting range and high-temperature joint strength9.5 – 10.510
Znvacuum-grade high-vapor-pressure element limit≤ 0—
Cdvacuum-grade limit≤ 0—
Pvacuum-grade limit≤ 0—
Other (total)total of other elements≤ 0.15—
Cubalance—

BVAg-31 AS-BRAZED — frequently asked

What is BVAg-31 AS-BRAZED used for?

BVAg-31 AS-BRAZED is typically used for vacuum furnace brazing of stainless steel assemblies, superalloy joints in turbine and engine hardware, vacuum-tight instrument and sensor housings, stainless steel heat exchanger cores, tube-to-fitting preform rings and RF and waveguide component brazing. In short: zinc-free vacuum silver braze; lower-temperature BVAg option; flux-free, clean fillets.

What is the yield strength of BVAg-31 AS-BRAZED?

BVAg-31 AS-BRAZED has a typical yield strength of 230 MPa (33.4 ksi) and a tensile strength of 400 MPa (58 ksi) — stronger than 70% of precious metal grades. Strength varies by condition: see the 2 listed tempers.

Is BVAg-31 AS-BRAZED easy to machine?

Not especially — machinability is rated fair (40/100, worse than 60% of precious metal grades). Rarely machined; the alloy is soft and gummy — use sharp, polished high-rake tools and collect all chips as precious-metal scrap.

Can BVAg-31 AS-BRAZED be welded?

Not readily — weldability is rated poor (30/100). Not a weld filler; joints are made by vacuum or dry-hydrogen furnace brazing at roughly 870–925 °C with a short soak to limit erosion of thin base metals.

What surface finishes work on BVAg-31 AS-BRAZED?

Fluxless brazing in vacuum leaves a bright, clean fillet needing no cleaning; if flux-brazed in air, remove residues with hot water/citric rinse before plating or passivation.

Can BVAg-31 AS-BRAZED be formed, bent or molded?

Excellent cold formability in the annealed state — drawn to fine wire, rolled to 25 µm foil and stamped into rings; interstage anneal near 650–700 °C in inert atmosphere.

What is the maximum service temperature of BVAg-31 AS-BRAZED?

BVAg-31 AS-BRAZED is rated for continuous use to about 450°C (842 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

Sources

  1. AWS A5.8/A5.8M Specification for Filler Metals for Brazing and Braze Welding — American Welding Society (2019)
  2. ASM Handbook Vol.6 — Welding, Brazing and Soldering (brazing filler metals) — ASM International (1993)
  3. Brazing Handbook, 5th ed. — American Welding Society (2007)
  4. Palladium-bearing silver braze alloy (Palcusil 10 type) technical data — brazing filler metal producers (2022)
  5. GB/T 10046 (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.