Solder & Low-Melting Alloy Bi50Pb25Sn25 vs Field's Metal
Solder & Low-Melting Alloy · grade comparison
Solder & Low-Melting Alloy Bi50Pb25Sn25 and Field's Metal are both solder & low-melting alloy grades. Bi50Pb25Sn25 is the stronger of the two: yield strength 18 MPa (2.61 ksi) against 6 MPa (0.87 ksi) for Field's Metal, about 3.0 times as much; tensile strength follows at 30 MPa (4.35 ksi) vs 11 MPa (1.6 ksi). In exchange, Field's Metal is the more ductile: elongation 40% versus 35% for Bi50Pb25Sn25, and Bi50Pb25Sn25 is harder (11 HB vs 7 HB). Field's Metal is lighter (7.88 g/cm³ vs 9.7 g/cm³ for Bi50Pb25Sn25) and Bi50Pb25Sn25 is stiffer (25 GPa vs 10 GPa). On the shop floor, Bi50Pb25Sn25 machines more easily (fair vs poor) and Field's Metal welds better (poor vs not recommended).
Bi50Pb25Sn25Choose it when strength drives the design, or when the part sees heat.
Field's MetalChoose it when the part is bent, formed or impact-loaded, or when weight is the constraint.
Bi50Pb25Sn25 vs Field's Metal: 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
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)
Min Service Temperature
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
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Castability
Polishability
Same in both: Brazeability / Solderability 95 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Embodied Water
Same in both: Typical Recycled Content 60%
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Modulus of Resilience
Thermal Diffusivity
Same in both: Thermal Shock Resistance Index 1
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 | Bi50Pb25Sn25 | Field's Metal |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$$$ High | $$$$ High |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Bi50Pb25Sn25 vs Field's Metal — frequently asked
Is Bi50Pb25Sn25 stronger than Field's Metal?
Yes. Bi50Pb25Sn25 has a typical yield strength of 18 MPa (2.61 ksi) against 6 MPa (0.87 ksi) for Field's Metal — about 3.0 times as much. Tensile strength is 30 MPa (4.35 ksi) vs 11 MPa (1.6 ksi).
Which is cheaper, Bi50Pb25Sn25 or Field's Metal?
Both sit in the same relative cost tier ($$$$, high); the part price will be decided by machining time, tolerance and quantity rather than by the material.
Which is easier to machine, Bi50Pb25Sn25 or Field's Metal?
Bi50Pb25Sn25. Its machinability rates fair (40/100) against poor (30/100) for Field's Metal; for welding the order is Field's Metal first (poor, 20/100) then Bi50Pb25Sn25 (not recommended, 10/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in Bi50Pb25Sn25 and Field's Metal 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.