Solder & Low-Melting Alloy Bi32.5In51Sn16.5 vs Bi58Sn42
Solder & Low-Melting Alloy · grade comparison
Solder & Low-Melting Alloy Bi32.5In51Sn16.5 and Bi58Sn42 are both solder & low-melting alloy grades. Bi58Sn42 is the stronger of the two: yield strength 42 MPa (6.09 ksi) against 8 MPa (1.16 ksi) for Bi32.5In51Sn16.5, about 5.3 times as much; tensile strength follows at 65 MPa (9.43 ksi) vs 15 MPa (2.18 ksi). In exchange, Bi32.5In51Sn16.5 is the more ductile: elongation 100% versus 40% for Bi58Sn42, and Bi58Sn42 is harder (22 HB vs 10 HB). Bi32.5In51Sn16.5 is lighter (7.88 g/cm³ vs 8.56 g/cm³ for Bi58Sn42) and Bi58Sn42 is stiffer (42 GPa vs 10 GPa).
Bi32.5In51Sn16.5Choose it when the part is bent, formed or impact-loaded, or when weight is the constraint.
Bi58Sn42Choose it when strength drives the design, or when the part sees heat.
Bi32.5In51Sn16.5 vs Bi58Sn42: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all solder & low-melting alloy grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all solder & low-melting alloy grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Elastic (Young's) Modulus
Shear Modulus
Bulk Modulus
Poisson's Ratio
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Compressive Strength
Shear Strength
Hardness, Brinell
Fatigue Strength (Endurance Limit)
Hardness, Vickers
Physical
Density and transition temperatures.
Density
Melting Point (Solidus)
Liquidus Temperature
Thermal
How each material carries heat and how hot it can run.
Specific Heat Capacity
Thermal Expansion (CTE, 20–100 °C)
Latent Heat of Fusion
Max Service Temperature (continuous)
Min Service Temperature
Same in both: Thermal Conductivity 19 W/m·K11 BTU/hr·ft·°F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Galvanic Potential (seawater, vs SCE)
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Formability (cold)
Castability
Brazeability / Solderability
Polishability
Same in both: Machinability 30 / 100 · Weldability 20 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Typical Recycled Content
Embodied Water
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Modulus of Resilience
Thermal Diffusivity
Thermal Shock Resistance Index
Strength versus weight
Yield strength against density for every solder & low-melting alloy grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
Manufacturing and finishing
| Capability | Bi32.5In51Sn16.5 | Bi58Sn42 |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$$$ High | $$$$ High |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Bi32.5In51Sn16.5 vs Bi58Sn42 — frequently asked
Is Bi58Sn42 stronger than Bi32.5In51Sn16.5?
Yes. Bi58Sn42 has a typical yield strength of 42 MPa (6.09 ksi) against 8 MPa (1.16 ksi) for Bi32.5In51Sn16.5 — about 5.3 times as much. Tensile strength is 65 MPa (9.43 ksi) vs 15 MPa (2.18 ksi).
Which is cheaper, Bi32.5In51Sn16.5 or Bi58Sn42?
Both sit in the same relative cost tier ($$$$, high); the part price will be decided by machining time, tolerance and quantity rather than by the material.
When should I choose Bi32.5In51Sn16.5 over Bi58Sn42?
Pick Bi32.5In51Sn16.5 when the part is bent, formed or impact-loaded, or when weight is the constraint. Pick Bi58Sn42 when strength drives the design, or when the part sees heat.
Ready to make it?
Upload a CAD file and FabDigit prices the part in Bi32.5In51Sn16.5 and Bi58Sn42 side by side — material, machining time, tolerance and finish in one quote. Certified material data ships with the order on request.
Typical handbook values for the conditions named above, normalised for comparison. Hardness on non-Brinell scales is converted approximately for charting only. Request certified data with your order for design-critical properties.
