Solder & Low-Melting Alloy Sn60Pb38Bi2
Sn60Pb38Bi2 is a tin-lead solder in which a 2 % bismuth addition slightly lowers the melting point and improves wetting.
Reference datasheet — Sn60Pb38Bi2 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 Sn60Pb38Bi2?
Sn60Pb38Bi2 is a tin-lead solder in which a 2 % bismuth addition slightly lowers the melting point and improves wetting. It was used historically for delicate or heat-sensitive component soldering and is available as bar, solid and flux-cored wire, paste, preforms and powder, with as-soldered values of 50 MPa tensile, 40 % elongation and 15 HB. Service is limited to about 100 °C, the lead content restricts it under RoHS, and bismuth must not meet lead-plated or Pb-Sn finishes where a 96 °C ternary phase can form. Sn60Pb40 or Sn63Pb37 is the direct substitute where the lower melting point is not required. Sn60Pb38Bi2 has a density of 8.5 g/cm³ (0.307 lb/in³), lighter than 52% of solder & low-melting alloy grades. It melts at 178°C (352 °F). Sn60Pb38Bi2 has a yield strength of 30 MPa (4.35 ksi) and a tensile strength of 50 MPa (7.25 ksi) — stronger than 61% of solder & low-melting alloy grades. Elongation at break is 40% and the elastic modulus is 30 GPa (4.35 Msi).
What is Sn60Pb38Bi2 used for?
- Heat-sensitive component soldering
- Fine electronics assembly
- Low-temperature hand rework
- Fine-pitch paste printing
- Preform and powder reflow joints
- Coil and sensor terminations
- Thin-wire and lead tinning
Sn60Pb38Bi2 properties
Typical room-temperature values; bars are the position among solder & low-melting alloy grades.
Physical3
Sn60Pb38Bi2 has a density of 8.5 g/cm³ (0.307 lb/in³), lighter than 52% of solder & low-melting alloy grades. It melts at 178°C (352 °F).
Mechanical11
Sn60Pb38Bi2 has a yield strength of 30 MPa (4.35 ksi) and a tensile strength of 50 MPa (7.25 ksi) — stronger than 61% of solder & low-melting alloy grades. Elongation at break is 40% and the elastic modulus is 30 GPa (4.35 Msi).
Thermal6
Sn60Pb38Bi2 is rated for continuous service to 100°C (212 °F). It conducts heat at 50 W/m·K (28.9 BTU/hr·ft·°F), better than 63% of solder & low-melting alloy grades. Thermal expansion is 24.5 µm/m·K (13.6 µin/in·°F).
Electrical3
Sn60Pb38Bi2 conducts electricity at 11.5 % IACS, better than 71% 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 Sn60Pb38Bi2 takes about 190 MJ of energy and emits 10.3 kg of CO₂ — more than 50% of solder & low-melting alloy grades. Typical recycled content is 25%.
Manufacturability5
Sn60Pb38Bi2's machinability is poor (30/100, worse than 60% 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. Sn60Pb38Bi2 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with Sn60Pb38Bi2
Is Sn60Pb38Bi2 easy to machine?
Rarely machined — extremely soft and gummy; use sharp high-rake tools, kerosene lubricant, and capture lead-bearing swarf as hazardous waste.
Can Sn60Pb38Bi2 be welded?
Not welded; it is itself a filler — soldering iron at 320–360 °C tip or wave pot at 250–260 °C, avoid overheating to limit Bi segregation and dross.
Can Sn60Pb38Bi2 be formed, bent or molded?
Cast into bars or extruded/drawn to wire and rolled to foil at room temperature; recrystallizes at RT so no annealing is needed.
Sn60Pb38Bi2 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 |
|---|---|---|
| Sn | 59.5 – 60.5 | 60 |
| Biwetting/melting-point modifier | 1.5 – 2.5 | 2 |
| Sbimpurity limit | ≤ 0.12 | |
| Cuimpurity limit | ≤ 0.05 | |
| Agimpurity limit | ≤ 0.05 | |
| Feimpurity limit | ≤ 0.02 | |
| Asimpurity limit | ≤ 0.03 | |
| Znimpurity limit — causes dewetting | ≤ 0 | |
| Alimpurity limit — causes dewetting | ≤ 0 | |
| Cdimpurity limit | ≤ 0 | |
| Pb | balance |
What surface finishes work on Sn60Pb38Bi2?
Joints are bright as-soldered; clean rosin residues with IPA or saponifier for no-clean/RMA, and avoid Bi-rich solder on Pb-Sn or Pb-plated finishes where a 96 °C ternary phase can form.
How much does Sn60Pb38Bi2 cost?
Sn60Pb38Bi2 is a high-cost solder & low-melting alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sn60Pb38Bi2 — frequently asked
What is Sn60Pb38Bi2 used for?
Sn60Pb38Bi2 is typically used for heat-sensitive component soldering, fine electronics assembly, low-temperature hand rework, fine-pitch paste printing, preform and powder reflow joints and coil and sensor terminations. In short: lower-melting Sn60Pb40; improved wetting variant; highest ductility leaded solder.
What is the yield strength of Sn60Pb38Bi2?
Sn60Pb38Bi2 has a typical yield strength of 30 MPa (4.35 ksi) and a tensile strength of 50 MPa (7.25 ksi) — stronger than 61% of solder & low-melting alloy grades.
Is Sn60Pb38Bi2 easy to machine?
Not especially — machinability is rated poor (30/100, worse than 60% of solder & low-melting alloy grades). Rarely machined — extremely soft and gummy; use sharp high-rake tools, kerosene lubricant, and capture lead-bearing swarf as hazardous waste.
Can Sn60Pb38Bi2 be welded?
Not welded; it is itself a filler — soldering iron at 320–360 °C tip or wave pot at 250–260 °C, avoid overheating to limit Bi segregation and dross.
What surface finishes work on Sn60Pb38Bi2?
Joints are bright as-soldered; clean rosin residues with IPA or saponifier for no-clean/RMA, and avoid Bi-rich solder on Pb-Sn or Pb-plated finishes where a 96 °C ternary phase can form.
Can Sn60Pb38Bi2 be formed, bent or molded?
Cast into bars or extruded/drawn to wire and rolled to foil at room temperature; recrystallizes at RT so no annealing is needed.
What is the maximum service temperature of Sn60Pb38Bi2?
Sn60Pb38Bi2 is rated for continuous use to about 100°C (212 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does Sn60Pb38Bi2 cost?
Sn60Pb38Bi2 is a high-cost solder & low-melting alloy ($$$$), 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
- ISO 9453 — Soft solder alloys: chemical compositions and forms (alloy 141, S-Sn60Pb38Bi2) — ISO (2020)
- GB/T 3131 — SAC/ (2020)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys (Solders) — ASM International (1990)
- NIST Solder Alloy Properties Database (Sn-Pb and Sn-Pb-Bi) — NIST (2002)
- Solder alloy datasheets (Sn-Pb-Bi wetting and melting range) — Indium Corporation / Alpha Assembly (2023)
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.