Solder & Low-Melting Alloy Pb49Sn48Bi3 vs Pb50Sn50
Solder & Low-Melting Alloy · grade comparison
Solder & Low-Melting Alloy Pb49Sn48Bi3 and Pb50Sn50 are both solder & low-melting alloy grades. Pb49Sn48Bi3 is the stronger of the two: tensile strength 45 MPa (6.53 ksi) against 42 MPa (6.09 ksi) for Pb50Sn50, about 7% more. In exchange, Pb50Sn50 is the more ductile: elongation 55% versus 40% for Pb49Sn48Bi3, and Pb49Sn48Bi3 is harder (14 HV vs 13 HV). Pb49Sn48Bi3 is stiffer (30 GPa vs 23 GPa).
Pb49Sn48Bi3Choose it when strength drives the design.
Pb50Sn50Choose it when the part is bent, formed or impact-loaded.
Pb49Sn48Bi3 vs Pb50Sn50: 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
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Shear Strength
Hardness, Vickers
Same in both: Poisson's Ratio 0.4 · Fatigue Strength (Endurance Limit) 14 MPa2 ksi · Hardness, Brinell 14 HB
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
Thermal Expansion (CTE, 20–100 °C)
Min Service Temperature
Same in both: Specific Heat Capacity 176 J/kg·K0.04 BTU/lb·°F · Latent Heat of Fusion 42 J/g18.1 BTU/lb · Max Service Temperature (continuous) 100°C212 °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
Weldability
Formability (cold)
Brazeability / Solderability
Machinability Rating (AISI 1212 = 100 %)
Same in both: Castability 90 / 100 · Polishability 20 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Embodied Water
Typical Recycled Content
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) 5 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 | Pb49Sn48Bi3 | Pb50Sn50 |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$$$ High | $$$$ High |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Pb49Sn48Bi3 vs Pb50Sn50 — frequently asked
Is Pb49Sn48Bi3 stronger than Pb50Sn50?
Yes. Pb49Sn48Bi3 has a typical tensile strength of 45 MPa (6.53 ksi) against 42 MPa (6.09 ksi) for Pb50Sn50 — about 7% more.
Which is cheaper, Pb49Sn48Bi3 or Pb50Sn50?
Both sit in the same relative cost tier ($$$$, high); the part price will be decided by machining time, tolerance and quantity rather than by the material.
Which is easier to machine, Pb49Sn48Bi3 or Pb50Sn50?
Pb50Sn50, by a small margin. Both rate poor for machinability — 30/100 against 25/100 for Pb49Sn48Bi3; for welding the order is Pb49Sn48Bi3 first (poor, 20/100) then Pb50Sn50 (poor, 15/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in Pb49Sn48Bi3 and Pb50Sn50 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.