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Solder & Low-Melting Alloy Sn60Pb39Cu1 vs Sn95Cu4Ag1

Solder & Low-Melting Alloy · grade comparison

Solder & Low-Melting Alloy Sn60Pb39Cu1 and Sn95Cu4Ag1 are both solder & low-melting alloy grades. Sn95Cu4Ag1 is the stronger of the two: yield strength 32 MPa (4.64 ksi) against 30 MPa (4.35 ksi) for Sn60Pb39Cu1, about 7% more. In exchange, Sn60Pb39Cu1 is the more ductile: elongation 35% versus 25% for Sn95Cu4Ag1, and Sn95Cu4Ag1 is harder (18 HB vs 16 HB). Sn95Cu4Ag1 is lighter (7.35 g/cm³ vs 8.5 g/cm³ for Sn60Pb39Cu1) and Sn95Cu4Ag1 is stiffer (48 GPa vs 30 GPa). On the shop floor, Sn95Cu4Ag1 machines more easily (30 vs 20 out of 100).

Sn60Pb39Cu1Choose it when the part is bent, formed or impact-loaded.

Sn95Cu4Ag1Choose it when strength drives the design, or when weight is the constraint.

Sn60Pb39Cu1 vs Sn95Cu4Ag1: properties

Sn60Pb39Cu1Sn95Cu4Ag1

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

30 GPa4.4 Msi
48 GPa7 Msi

Shear Modulus

11 GPa1.6 Msi
18 GPa2.6 Msi

Bulk Modulus

43 GPa6.2 Msi
55 GPa8 Msi

Poisson's Ratio

0.38
0.36

Tensile Strength (Ultimate)

52 MPa7.5 ksi
48 MPa7 ksi

Yield Strength (0.2% offset)

30 MPa4.4 ksi
32 MPa4.6 ksi

Elongation at Break

35%
25%

Shear Strength

36 MPa5.2 ksi
30 MPa4.4 ksi

Fatigue Strength (Endurance Limit)

16 MPa2.3 ksi
20 MPa2.9 ksi

Hardness, Brinell

16 HB
18 HB

Hardness, Vickers

17 HV
—

Compressive Strength

—
45 MPa6.5 ksi

Physical

Density and transition temperatures.

Density

8.5 g/cm³0.31 lb/in³
7.35 g/cm³0.27 lb/in³

Melting Point (Solidus)

183°C361 °F
217°C423 °F

Liquidus Temperature

192°C378 °F
330°C626 °F

Thermal

How each material carries heat and how hot it can run.

Thermal Conductivity

50 W/m·K28.9 BTU/hr·ft·°F
60 W/m·K34.7 BTU/hr·ft·°F

Specific Heat Capacity

180 J/kg·K0.04 BTU/lb·°F
230 J/kg·K0.05 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

24.5 µm/m·K13.6 µin/in·°F
22.5 µm/m·K12.5 µin/in·°F

Latent Heat of Fusion

42 J/g18.1 BTU/lb
60 J/g25.8 BTU/lb

Max Service Temperature (continuous)

100°C212 °F
150°C302 °F

Same in both: Min Service Temperature -55°C-67 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 11.5 % IACS · Electrical Resistivity 1.5×10⁻⁷ Ω·m5.91 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.5 V · Corrosion Resistance 45 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability

20 / 100
30 / 100

Castability

90 / 100
80 / 100

Brazeability / Solderability

98 / 100
90 / 100

Same in both: Weldability 20 / 100 · Formability (cold) 90 / 100 · Polishability 25 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

205 MJ/kg88,134 BTU/lb
330 MJ/kg141,875 BTU/lb

Embodied Carbon (primary production)

10.5 kg CO₂/kg
17 kg CO₂/kg

Embodied Water

400 L/kg47.9 gal/lb
250 L/kg30 gal/lb

Typical Recycled Content

35%
30%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

6 kN·m/kg
7 kN·m/kg

Specific Stiffness (E / density)

3.5 MN·m/kg
6.5 MN·m/kg

Modulus of Resilience

15 kJ/m³
11 kJ/m³

Thermal Diffusivity

32.7 mm²/s
35.5 mm²/s

Thermal Shock Resistance Index

4
3

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.

125102050891011Density (g/cm³)Yield strength (MPa) — log scaleSn60Pb39Cu1Sn95Cu4Ag1

Manufacturing and finishing

CapabilitySn60Pb39Cu1Sn95Cu4Ag1
Default condition——
Relative cost$$$$ High$$$$ High
Min. machined wall——
Best machined surface——

Sn60Pb39Cu1 vs Sn95Cu4Ag1 — frequently asked

Is Sn95Cu4Ag1 stronger than Sn60Pb39Cu1?

Yes. Sn95Cu4Ag1 has a typical yield strength of 32 MPa (4.64 ksi) against 30 MPa (4.35 ksi) for Sn60Pb39Cu1 — about 7% more. Tensile strength is 48 MPa (6.96 ksi) vs 52 MPa (7.54 ksi).

Which is cheaper, Sn60Pb39Cu1 or Sn95Cu4Ag1?

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, Sn60Pb39Cu1 or Sn95Cu4Ag1?

Sn95Cu4Ag1, by a small margin. Both rate poor for machinability — 30/100 against 20/100 for Sn60Pb39Cu1.

Ready to make it?

Upload a CAD file and FabDigit prices the part in Sn60Pb39Cu1 and Sn95Cu4Ag1 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.