Precious Metal Ag120
EN L-Ag20Sn · GB BAg20CuZnSn
EN ISO 17672 Ag120 (L-Ag20Sn, BAg20CuZnSn) is an economy-grade low-silver cadmium-free Ag-Cu-Zn-Sn braze filler for cost-sensitive copper and brass joints where lower joint strength is acceptable.
Reference datasheet — Ag120 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.
What is Ag120?
EN ISO 17672 Ag120 (L-Ag20Sn, BAg20CuZnSn) is an economy-grade low-silver cadmium-free Ag-Cu-Zn-Sn braze filler for cost-sensitive copper and brass joints where lower joint strength is acceptable. It is supplied as wire/rod, flux-coated rod, strip, preforms and powder or paste, and as-brazed deposits show 420 MPa tensile strength with 20 % elongation. The trade-off is a working temperature of about 810–830 °C, which puts more heat into the base metal and increases zinc loss if the joint is held hot; vacuum furnace brazing is not an option. Ag130 or Ag134 are the next steps up when a lower brazing temperature is needed. Ag120 has a density of 8.6 g/cm³ (0.311 lb/in³), lighter than 98% of precious metal grades. It melts at 690°C (1,274 °F). Ag120 has a yield strength of 300 MPa (43.5 ksi) and a tensile strength of 420 MPa (60.9 ksi) — stronger than 91% of precious metal grades. Elongation at break is 20% and the elastic modulus is 92 GPa (13.3 Msi).
What is Ag120 used for?
- general plumbing
- low-stress copper joints
- HVAC ductwork accessories
Advantages
- Low embodied carbon — 25 kg CO₂/kg, better than 99% of precious metal grades
- Lightweight — 8.6 g/cm³ (0.311 lb/in³), better than 98% of precious metal grades
- High strength — 300 MPa (43.5 ksi), better than 91% of precious metal grades
Limitations
- Needs corrosion protection — 45/100, worse than 100% of precious metal grades
- Hard to polish — 60/100, worse than 92% of precious metal grades
- Limited service temperature — 200°C (392 °F), worse than 89% of precious metal grades
- Limited formability — 55/100, worse than 89% of precious metal grades
- Limited ductility — 20%, worse than 77% of precious metal grades
Ag120 properties
Typical room-temperature values; bars are the position among precious metal grades.
Physical3
Ag120 has a density of 8.6 g/cm³ (0.311 lb/in³), lighter than 98% of precious metal grades. It melts at 690°C (1,274 °F).
Mechanical11
Ag120 has a yield strength of 300 MPa (43.5 ksi) and a tensile strength of 420 MPa (60.9 ksi) — stronger than 91% of precious metal grades. Elongation at break is 20% and the elastic modulus is 92 GPa (13.3 Msi).
Thermal6
Ag120 is rated for continuous service to 200°C (392 °F). It conducts heat at 75 W/m·K (43.3 BTU/hr·ft·°F), worse than 57% of precious metal grades. Thermal expansion is 19 µm/m·K (10.6 µin/in·°F).
Electrical3
Ag120 conducts electricity at 12 % IACS, worse than 74% of precious metal grades.
Chemical & Environmental3
Corrosion resistance is fair (45/100), worse than 100% of precious metal grades.
Sustainability4
Producing a kilogram of Ag120 takes about 350 MJ of energy and emits 25 kg of CO₂ — less than 99% of precious metal grades. Typical recycled content is 45%.
Manufacturability4
Ag120's machinability is fair (45/100, better than 59% of precious metal grades); formability good (55/100).
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. Ag120 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with Ag120
Is Ag120 easy to machine?
The filler is not machined as a structural material; the solidified fillet is soft and grabs the tool, so dress it with a file or grinding wheel rather than by turning.
Can Ag120 be welded?
Used as a braze filler with oxy-acetylene or propane flame, induction or furnace heating at a working temperature of about 810–830 °C. A borax-fluoride silver brazing flux is required, and prolonged overheating must be avoided to prevent zinc volatilisation.
Can Ag120 be formed, bent or molded?
Can be drawn to wire, rolled to strip and stamped into braze rings; anneal between cold-working passes, as higher tin content increases brittleness.
Ag120 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 | 19 – 21 | 20 |
| Cu | 43 – 45 | 44 |
| Snreplaces Cd, lowers melting point and improves wetting | 1.5 – 2.5 | 2 |
| Cdcadmium-free grade, impurity limit | ≤ 0.01 | 0 |
| Pbimpurity | ≤ 0.03 | — |
| Others (total)total of other impurities | ≤ 0.15 | — |
| Zn | balance | — |
What surface finishes work on Ag120?
Wash thoroughly in hot water or dilute acid after brazing to remove flux residue and prevent corrosion. Joints can be polished, nickel plated or chrome plated, but a protective coating is advised in dezincification-sensitive environments.
Equivalent designations
Standards and trade names that resolve to Precious Metal Ag120 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- EN / DIN / Werkstoff-Nr.
- L-Ag20Sn
- GB (China)
- BAg20CuZnSn
How much does Ag120 cost?
Ag120 is a high-cost precious metal ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Ag120 — frequently asked
What is Ag120 used for?
Ag120 is typically used for general plumbing, low-stress copper joints and HVAC ductwork accessories. In short: lowest-cost cadmium-free BAg; 20 % silver economy filler; highest working temperature here.
What is the yield strength of Ag120?
Ag120 has a typical yield strength of 300 MPa (43.5 ksi) and a tensile strength of 420 MPa (60.9 ksi) — stronger than 91% of precious metal grades.
Is Ag120 easy to machine?
Reasonably — machinability is rated fair (45/100, better than 59% of precious metal grades). The filler is not machined as a structural material; the solidified fillet is soft and grabs the tool, so dress it with a file or grinding wheel rather than by turning.
Can Ag120 be welded?
Used as a braze filler with oxy-acetylene or propane flame, induction or furnace heating at a working temperature of about 810–830 °C. A borax-fluoride silver brazing flux is required, and prolonged overheating must be avoided to prevent zinc volatilisation.
What surface finishes work on Ag120?
Wash thoroughly in hot water or dilute acid after brazing to remove flux residue and prevent corrosion. Joints can be polished, nickel plated or chrome plated, but a protective coating is advised in dezincification-sensitive environments.
Can Ag120 be formed, bent or molded?
Can be drawn to wire, rolled to strip and stamped into braze rings; anneal between cold-working passes, as higher tin content increases brittleness.
What is the maximum service temperature of Ag120?
Ag120 is rated for continuous use to about 200°C (392 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does Ag120 cost?
Ag120 is a high-cost precious metal ($$$$), 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
- EN ISO 17672 Brazing — Filler metals (Ag 120) — ISO/CEN (2016)
- DIN 8513-2 L-Ag20Sn (superseded designation) — DIN (2000)
- ASM Handbook Vol.6 — Welding, Brazing and Soldering (silver filler metals) — ASM International (1993)
- Cadmium-free silver brazing alloy datasheets (Ag 20% class) — Lucas-Milhaupt / Umicore / (2023)
- GB/T 10046 (2018)
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.