Solder & Low-Melting Alloy Sn60Pb40Sb vs Sn91Zn9
Solder & Low-Melting Alloy · grade comparison
Solder & Low-Melting Alloy Sn60Pb40Sb and Sn91Zn9 are both solder & low-melting alloy grades. Sn91Zn9 is the stronger of the two: yield strength 38 MPa (5.51 ksi) against 32 MPa (4.64 ksi) for Sn60Pb40Sb, about 19% more; tensile strength follows at 65 MPa (9.43 ksi) vs 52 MPa (7.54 ksi). Sn91Zn9 is the more ductile: elongation 40% versus 35% for Sn60Pb40Sb, and Sn91Zn9 is harder (21 HB vs 15 HB). Sn91Zn9 is lighter (7.27 g/cm³ vs 8.5 g/cm³ for Sn60Pb40Sb) and Sn91Zn9 is stiffer (40 GPa vs 31 GPa).
Sn60Pb40SbChoose it when the part sees heat.
Sn91Zn9Choose it when strength drives the design, or when the part is bent, formed or impact-loaded.
Sn60Pb40Sb vs Sn91Zn9: 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
Shear Strength
Fatigue Strength (Endurance Limit)
Charpy V-Notch Impact (RT)
Hardness, Brinell
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.
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
Castability
Brazeability / Solderability
Polishability
Same in both: Weldability 10 / 100 · Formability (cold) 85 / 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 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 | Sn60Pb40Sb | Sn91Zn9 |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$$$ High | $$$$ High |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Sn60Pb40Sb vs Sn91Zn9 — frequently asked
Is Sn91Zn9 stronger than Sn60Pb40Sb?
Yes. Sn91Zn9 has a typical yield strength of 38 MPa (5.51 ksi) against 32 MPa (4.64 ksi) for Sn60Pb40Sb — about 19% more. Tensile strength is 65 MPa (9.43 ksi) vs 52 MPa (7.54 ksi).
Which is cheaper, Sn60Pb40Sb or Sn91Zn9?
Both sit in the same relative cost tier ($$$$, high); the part price will be decided by machining time, tolerance and quantity rather than by the material.
Which is easier to machine, Sn60Pb40Sb or Sn91Zn9?
Sn60Pb40Sb. Its machinability rates fair (35/100) against poor (30/100) for Sn91Zn9.
Ready to make it?
Upload a CAD file and FabDigit prices the part in Sn60Pb40Sb and Sn91Zn9 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.