Solder & Low-Melting Alloy Sn42Bi58 vs Sn63Pb37Sb
Solder & Low-Melting Alloy · grade comparison
Solder & Low-Melting Alloy Sn42Bi58 and Sn63Pb37Sb are both solder & low-melting alloy grades. Sn42Bi58 is the stronger of the two: yield strength 42 MPa (6.09 ksi) against 38 MPa (5.51 ksi) for Sn63Pb37Sb, about 11% more; tensile strength follows at 62 MPa (8.99 ksi) vs 58 MPa (8.41 ksi). Sn42Bi58 is harder — 22 HB against 16 HB for Sn63Pb37Sb — which matters for wear surfaces and threads. Sn42Bi58 is stiffer (42 GPa vs 32 GPa) and Sn63Pb37Sb runs hotter in service (100°C vs 85°C continuous). On the shop floor, Sn42Bi58 machines more easily (good vs poor) and Sn63Pb37Sb forms better (excellent vs fair).
Sn42Bi58Choose it when strength drives the design, or when surface hardness matters.
Sn63Pb37SbChoose it when the part sees heat.
Sn42Bi58 vs Sn63Pb37Sb: 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
Fatigue Strength (Endurance Limit)
Hardness, Brinell
Hardness, Vickers
Same in both: Shear Strength 38 MPa5.5 ksi
Physical
Density and transition temperatures.
Density
Melting Point (Solidus)
Liquidus Temperature
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Specific Heat Capacity
Thermal Expansion (CTE, 20–100 °C)
Latent Heat of Fusion
Max Service Temperature (continuous)
Same in both: Min Service Temperature -55°C-67 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Galvanic Potential (seawater, vs SCE)
Corrosion Resistance
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Formability (cold)
Castability
Brazeability / Solderability
Polishability
Same in both: 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 Stiffness (E / density)
Modulus of Resilience
Thermal Diffusivity
Thermal Shock Resistance Index
Same in both: Specific Strength (UTS / density) 7 kN·m/kg
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 | Sn42Bi58 | Sn63Pb37Sb |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$$$ High | $$$$ High |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Sn42Bi58 vs Sn63Pb37Sb — frequently asked
Is Sn42Bi58 stronger than Sn63Pb37Sb?
Yes. Sn42Bi58 has a typical yield strength of 42 MPa (6.09 ksi) against 38 MPa (5.51 ksi) for Sn63Pb37Sb — about 11% more. Tensile strength is 62 MPa (8.99 ksi) vs 58 MPa (8.41 ksi).
Which is cheaper, Sn42Bi58 or Sn63Pb37Sb?
Both sit in the same relative cost tier ($$$$, high); the part price will be decided by machining time, tolerance and quantity rather than by the material.
Which is easier to machine, Sn42Bi58 or Sn63Pb37Sb?
Sn42Bi58. Its machinability rates good (55/100) against poor (20/100) for Sn63Pb37Sb.
Ready to make it?
Upload a CAD file and FabDigit prices the part in Sn42Bi58 and Sn63Pb37Sb 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.