Precious Metal PSr25
GOST PSr25 (ПСр25)
ПСр25 is a lower-silver Ag-Cu-Zn braze filler to GOST 19738, used for cost-sensitive copper and steel joints.
Reference datasheet — PSr25 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
PSr25 tempers and conditions
PSr25 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 PSr25 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
ANN-STRIP | Annealed strip / foil / preform stock | Supply form |
FLUX-COATED | Flux-coated brazing rod | Supply form |
POWDER-PASTE | Atomised powder / flux-mixed brazing paste | Supply form |
Wire-Drawn | Hard-drawn wire / rod | Supply form |
What is PSr25?
ПСр25 is a lower-silver Ag-Cu-Zn braze filler to GOST 19738, used for cost-sensitive copper and steel joints. It brazes at 780–830 °C with a fluoride-boride flux and gives about 350 MPa tensile, 20 % elongation and 95 HB, with service to roughly 200 °C; forms include drawn wire, annealed strip, powder/paste and flux-coated rod. The reduced silver content widens the melting range, so heat control and joint clearance matter more than with 45 % Ag fillers, and the zinc content excludes vacuum brazing. Move up to ПСр45 for tighter gaps, better flow or higher joint strength. PSr25 has a density of 8.7 g/cm³ (0.314 lb/in³), lighter than 96% of precious metal grades. It melts at 745°C (1,373 °F). PSr25 has a yield strength of 200 MPa (29 ksi) and a tensile strength of 350 MPa (50.8 ksi) — stronger than 51% of precious metal grades. Elongation at break is 20% and the elastic modulus is 95 GPa (13.8 Msi).
What is PSr25 used for?
- general steel brazing
- low-stress copper assemblies
- maintenance and repair brazing
Advantages
- Lightweight — 8.7 g/cm³ (0.314 lb/in³), better than 96% of precious metal grades
- Low embodied carbon — 55 kg CO₂/kg, better than 86% of precious metal grades
Limitations
- Limited service temperature — 200°C (392 °F), worse than 89% of precious metal grades
- Difficult to weld — 20/100, worse than 86% of precious metal grades
- Needs corrosion protection — 62/100, worse than 83% of precious metal grades
- Limited formability — 70/100, worse than 78% of precious metal grades
- Limited ductility — 20%, worse than 77% of precious metal grades
PSr25 properties
Typical room-temperature values for PSr25-AS-BRAZED; bars are the position among precious metal grades.
Physical3
PSr25 has a density of 8.7 g/cm³ (0.314 lb/in³), lighter than 96% of precious metal grades. It melts at 745°C (1,373 °F).
Mechanical10
PSr25 has a yield strength of 200 MPa (29 ksi) and a tensile strength of 350 MPa (50.8 ksi) — stronger than 51% of precious metal grades. Elongation at break is 20% and the elastic modulus is 95 GPa (13.8 Msi).
Thermal6
PSr25 is rated for continuous service to 200°C (392 °F). It conducts heat at 95 W/m·K (54.9 BTU/hr·ft·°F), better than 51% of precious metal grades. Thermal expansion is 19 µm/m·K (10.6 µin/in·°F).
Electrical3
PSr25 conducts electricity at 19 % IACS, worse than 51% of precious metal grades.
Chemical & Environmental3
Corrosion resistance is good (62/100), worse than 83% of precious metal grades.
Sustainability4
Producing a kilogram of PSr25 takes about 440 MJ of energy and emits 55 kg of CO₂ — less than 97% of precious metal grades. Typical recycled content is 45%.
Manufacturability6
PSr25's machinability is fair (45/100, better than 59% of precious metal grades); weldability poor (20/100); formability very good (70/100).
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. PSr25 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with PSr25
Is PSr25 easy to machine?
Rarely machined — soft and gummy; supply as drawn wire, rolled strip, stamped preform or atomised powder instead.
Can PSr25 be welded?
Not a structural weldable alloy; it is the filler itself — join with torch, induction, furnace or resistance brazing at 780–830 °C using a fluoride-boride flux (GOST 23178 / FH10-type).
Can PSr25 be formed, bent or molded?
Ductile enough for wire drawing, foil rolling and preform stamping; anneal between heavy reductions to avoid Zn-rich phase cracking.
PSr25 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 |
|---|---|---|
| Agsilver content defining the grade | 24.7 – 25.3 | 25 |
| Cu | 39 – 41 | 40 |
| Pbimpurity limit | ≤ 0.15 | — |
| Feimpurity limit | ≤ 0.1 | — |
| Biimpurity limit | ≤ 0.01 | — |
| total impuritiessum of accompanying impurities per GOST 19738 | ≤ 0.5 | — |
| Znbalance, approx. 35 % | balance | — |
What surface finishes work on PSr25?
Remove all flux residue by hot-water/acid wash to prevent corrosion; the fillet can be wire-brushed or polished, and takes electroplated Ni/Sn if a uniform surface is needed.
Equivalent designations
Standards and trade names that resolve to Precious Metal PSr25 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- GOST
- ПСр25
How much does PSr25 cost?
PSr25 is a high-cost precious metal ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
PSr25 — frequently asked
What is PSr25 used for?
PSr25 is typically used for general steel brazing, low-stress copper assemblies and maintenance and repair brazing. In short: lowest-silver GOST braze; cost-driven general brazing; wider melting range.
What is the yield strength of PSr25?
PSr25 has a typical yield strength of 200 MPa (29 ksi) and a tensile strength of 350 MPa (50.8 ksi) — stronger than 51% of precious metal grades.
Is PSr25 easy to machine?
Reasonably — machinability is rated fair (45/100, better than 59% of precious metal grades). Rarely machined — soft and gummy; supply as drawn wire, rolled strip, stamped preform or atomised powder instead.
Can PSr25 be welded?
Not readily — weldability is rated poor (20/100). Not a structural weldable alloy; it is the filler itself — join with torch, induction, furnace or resistance brazing at 780–830 °C using a fluoride-boride flux (GOST 23178 / FH10-type).
What surface finishes work on PSr25?
Remove all flux residue by hot-water/acid wash to prevent corrosion; the fillet can be wire-brushed or polished, and takes electroplated Ni/Sn if a uniform surface is needed.
Can PSr25 be formed, bent or molded?
Ductile enough for wire drawing, foil rolling and preform stamping; anneal between heavy reductions to avoid Zn-rich phase cracking.
What is the maximum service temperature of PSr25?
PSr25 is rated for continuous use to about 200°C (392 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does PSr25 cost?
PSr25 is a high-cost precious metal ($$$$), 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
- GOST 19738-74 Припои серебряные. Марки — Gosstandart (1974)
- ISO 17672 Brazing — Filler metals (Ag 125 analogue) — ISO (2016)
- EN 1044 AG 205 silver brazing filler metal — CEN (1999)
- ASM Handbook Vol. 6 — Welding, Brazing and Soldering — ASM International (1993)
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.