Solder & Low-Melting Alloy Sn95Sb5 vs Sn97Cu3
Solder & Low-Melting Alloy · grade comparison
Solder & Low-Melting Alloy Sn95Sb5 and Sn97Cu3 are both solder & low-melting alloy grades. Sn95Sb5 is the stronger of the two: yield strength 30 MPa (4.35 ksi) against 25 MPa (3.63 ksi) for Sn97Cu3, about 20% more; tensile strength follows at 40 MPa (5.8 ksi) vs 35 MPa (5.08 ksi). Sn97Cu3 is harder — 15 HB against 13 HB for Sn95Sb5 — which matters for wear surfaces and threads. Sn95Sb5 is stiffer (48 GPa vs 45 GPa) and Sn95Sb5 runs hotter in service (150°C vs 125°C continuous).
Sn95Sb5Choose it when strength drives the design, or when the part sees heat.
Sn97Cu3Choose it when surface hardness matters.
Sn95Sb5 vs Sn97Cu3: 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
Poisson's Ratio
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Shear Strength
Fatigue Strength (Endurance Limit)
Hardness, Brinell
Same in both: Bulk Modulus 55 GPa8 Msi
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)
Max Service Temperature (continuous)
Min Service Temperature
Same in both: Latent Heat of Fusion 60 J/g25.8 BTU/lb
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.5 V
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Formability (cold)
Castability
Polishability
Same in both: Machinability 30 / 100 · Weldability 20 / 100 · Brazeability / Solderability 80 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Water
Same in both: Embodied Carbon (primary production) 18 kg CO₂/kg · Typical Recycled Content 30%
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 | Sn95Sb5 | Sn97Cu3 |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$$$ High | $$$$ High |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Sn95Sb5 vs Sn97Cu3 — frequently asked
Is Sn95Sb5 stronger than Sn97Cu3?
Yes. Sn95Sb5 has a typical yield strength of 30 MPa (4.35 ksi) against 25 MPa (3.63 ksi) for Sn97Cu3 — about 20% more. Tensile strength is 40 MPa (5.8 ksi) vs 35 MPa (5.08 ksi).
Which is cheaper, Sn95Sb5 or Sn97Cu3?
Both sit in the same relative cost tier ($$$$, high); the part price will be decided by machining time, tolerance and quantity rather than by the material.
When should I choose Sn95Sb5 over Sn97Cu3?
Pick Sn95Sb5 when strength drives the design, or when the part sees heat. Pick Sn97Cu3 when surface hardness matters.
Ready to make it?
Upload a CAD file and FabDigit prices the part in Sn95Sb5 and Sn97Cu3 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.