Solder & Low-Melting Alloy Sn96.5Ag3.5
Sn96.5Ag3.5 is the true eutectic tin-silver composition, melting sharply at 221 °C, with about 55 MPa tensile, 35 MPa yield, 40% elongation and 15 HB.
Reference datasheet — Sn96.5Ag3.5 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 Sn96.5Ag3.5?
Sn96.5Ag3.5 is the true eutectic tin-silver composition, melting sharply at 221 °C, with about 55 MPa tensile, 35 MPa yield, 40% elongation and 15 HB. It was the mainstream lead-free solder for wave soldering, plumbing and electronics before widespread SAC adoption and is supplied as bar, solid and cored wire, paste, foil, preform, spheres and plumbing coils. Service temperature is limited to roughly 125 °C and the 3.5% silver keeps cost above Sn-Cu alloys. SAC305 is the nearest alternative where copper-bearing joint metallurgy is preferred. Sn96.5Ag3.5 has a density of 7.37 g/cm³ (0.266 lb/in³), lighter than 78% of solder & low-melting alloy grades. It melts at 221°C (430 °F). Sn96.5Ag3.5 has a yield strength of 35 MPa (5.08 ksi) and a tensile strength of 55 MPa (7.98 ksi) — stronger than 81% of solder & low-melting alloy grades. Elongation at break is 40% and the elastic modulus is 50 GPa (7.25 Msi).
What is Sn96.5Ag3.5 used for?
- lead-free wave soldering
- plumbing/potable water fittings
- electronics assembly
- jewelry/silverware soldering
Advantages
- High electrical conductivity — 16 % IACS, better than 98% of solder & low-melting alloy grades
- Stiff — 50 GPa (7.25 Msi), better than 86% of solder & low-melting alloy grades
- High strength — 35 MPa (5.08 ksi), better than 81% of solder & low-melting alloy grades
- High service temperature — 125°C (257 °F), better than 80% of solder & low-melting alloy grades
- Lightweight — 7.37 g/cm³ (0.266 lb/in³), better than 78% of solder & low-melting alloy grades
Limitations
- High embodied carbon — 21 kg CO₂/kg, worse than 89% of solder & low-melting alloy grades
- Poor heat conductor — 33 W/m·K (19.1 BTU/hr·ft·°F), worse than 76% of solder & low-melting alloy grades
Sn96.5Ag3.5 properties
Typical room-temperature values; bars are the position among solder & low-melting alloy grades.
Physical3
Sn96.5Ag3.5 has a density of 7.37 g/cm³ (0.266 lb/in³), lighter than 78% of solder & low-melting alloy grades. It melts at 221°C (430 °F).
Mechanical10
Sn96.5Ag3.5 has a yield strength of 35 MPa (5.08 ksi) and a tensile strength of 55 MPa (7.98 ksi) — stronger than 81% of solder & low-melting alloy grades. Elongation at break is 40% and the elastic modulus is 50 GPa (7.25 Msi).
Thermal6
Sn96.5Ag3.5 is rated for continuous service to 125°C (257 °F). It conducts heat at 33 W/m·K (19.1 BTU/hr·ft·°F), worse than 76% of solder & low-melting alloy grades. Thermal expansion is 22 µm/m·K (12.2 µin/in·°F).
Electrical3
Sn96.5Ag3.5 conducts electricity at 16 % IACS, better than 98% of solder & low-melting alloy grades.
Chemical & Environmental3
Corrosion resistance is fair (45/100), worse than 52% of solder & low-melting alloy grades.
Sustainability4
Producing a kilogram of Sn96.5Ag3.5 takes about 300 MJ of energy and emits 21 kg of CO₂ — more than 73% of solder & low-melting alloy grades. Typical recycled content is 25%.
Manufacturability5
Sn96.5Ag3.5's machinability is poor (25/100, worse than 82% of solder & low-melting alloy grades); formability excellent (90/100).
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 solder & low-melting alloy family
Yield strength against density for every solder & low-melting alloy grade FabDigit runs. Sn96.5Ag3.5 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with Sn96.5Ag3.5
Is Sn96.5Ag3.5 easy to machine?
Rarely machined — extremely soft and gummy; use sharp tools, high rake and coolant/lubricant, or simply punch/shear preforms from foil.
Can Sn96.5Ag3.5 be welded?
Not welded; it is itself a filler — joints are made by reflow/wave/iron soldering at 240–270 °C with RA, RMA or no-clean flux on Cu, Ni, Ag or OSP surfaces.
Can Sn96.5Ag3.5 be formed, bent or molded?
Excellent hot/cold workability: extrudes to bar, draws to 0.3–1.5 mm wire (solid or flux-cored), rolls to foil and atomises to Type 3/4 powder for paste.
Sn96.5Ag3.5 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 |
|---|---|---|
| AgISO 9453 alloy 703 / J-STD-006 Sn96.5Ag3.5; ASTM B32 Sn96 narrows to 3.4–3.6 | 3.2 – 3.8 | 3.5 |
| Pbimpurity max; ≤0.05 for RoHS/lead-free plumbing grades | ≤ 0.1 | |
| Sbimpurity max | ≤ 0.1 | |
| Cuimpurity max | ≤ 0.05 | |
| Biimpurity max | ≤ 0.1 | |
| Feimpurity max | ≤ 0.02 | |
| Znimpurity max — degrades wetting | ≤ 0.01 | |
| Alimpurity max — degrades wetting | ≤ 0.01 | |
| Asimpurity max | ≤ 0.03 | |
| Cdimpurity max | ≤ 0 | |
| Snremainder, nominally 96.5 % | balance |
What surface finishes work on Sn96.5Ag3.5?
No plating or anodizing; keep surfaces oxide-free with clean flux, remove halide residues by wash or use no-clean chemistry, and store cool to limit oxide/whisker growth.
Equivalent designations
Standards and trade names that resolve to Solder & Low-Melting Alloy Sn96.5Ag3.5 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Also called
- IEC A35Sn96.5
How much does Sn96.5Ag3.5 cost?
Sn96.5Ag3.5 is a high-cost solder & low-melting alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sn96.5Ag3.5 — frequently asked
What is Sn96.5Ag3.5 used for?
Sn96.5Ag3.5 is typically used for lead-free wave soldering, plumbing/potable water fittings, electronics assembly and jewelry/silverware soldering. In short: true eutectic Sn-Ag; sharp 221 °C melt; potable-water plumbing grade.
What is the yield strength of Sn96.5Ag3.5?
Sn96.5Ag3.5 has a typical yield strength of 35 MPa (5.08 ksi) and a tensile strength of 55 MPa (7.98 ksi) — stronger than 81% of solder & low-melting alloy grades.
Is Sn96.5Ag3.5 easy to machine?
Not especially — machinability is rated poor (25/100, worse than 82% of solder & low-melting alloy grades). Rarely machined — extremely soft and gummy; use sharp tools, high rake and coolant/lubricant, or simply punch/shear preforms from foil.
Can Sn96.5Ag3.5 be welded?
Not welded; it is itself a filler — joints are made by reflow/wave/iron soldering at 240–270 °C with RA, RMA or no-clean flux on Cu, Ni, Ag or OSP surfaces.
What surface finishes work on Sn96.5Ag3.5?
No plating or anodizing; keep surfaces oxide-free with clean flux, remove halide residues by wash or use no-clean chemistry, and store cool to limit oxide/whisker growth.
Can Sn96.5Ag3.5 be formed, bent or molded?
Excellent hot/cold workability: extrudes to bar, draws to 0.3–1.5 mm wire (solid or flux-cored), rolls to foil and atomises to Type 3/4 powder for paste.
What is the maximum service temperature of Sn96.5Ag3.5?
Sn96.5Ag3.5 is rated for continuous use to about 125°C (257 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does Sn96.5Ag3.5 cost?
Sn96.5Ag3.5 is a high-cost solder & low-melting alloy ($$$$), 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
- ASTM B32 — Standard Specification for Solder Metal (Sn96 alloy) — ASTM International (2020)
- ISO 9453 — Soft solder alloys, chemical composition and forms (alloy 703) — ISO (2020)
- J-STD-006 — Requirements for Electronic Grade Solder Alloys — IPC (2013)
- GB/T 20422 — (Lead-free solder) (2018)
- Properties of Lead-Free Solders / Solder Interconnect Database — NIST (2002)
- Sn96.5/Ag3.5 alloy technical data — Indium Corporation (2023)
- ASM Handbook Vol. 6 — Welding, Brazing and Soldering (soldering alloys) — 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.