ISO Solder Alloy 117 (Pb80Sn20)
Solder alloy 117 is a lead-based soldering alloy. Cited properties are appropriate for the as-fabricated (no temper or treatment) condition. 117 is the ISO numeric designation for this material. Older literature may refer to this material as S-Pb80Sn20, but this is now discouraged.
It has the lowest electrical conductivity and a moderately low ductility among lead-based solder alloys.
The graph bars on the material properties cards below compare solder alloy 117 to: lead-based solder alloys (top), all alloys in the same category (middle), and the entire database (bottom). A full bar means this is the highest value in the relevant set. A half-full bar means it's 50% of the highest, and so on.
Mechanical Properties
Brinell Hardness
11
Elastic (Young's, Tensile) Modulus
23 GPa 3.3 x 106 psi
Elongation at Break
20 %
Poisson's Ratio
0.42
Shear Modulus
8.1 GPa 1.2 x 106 psi
Tensile Strength: Ultimate (UTS)
33 MPa 4.8 x 103 psi
Thermal Properties
Latent Heat of Fusion
31 J/g
Melting Completion (Liquidus)
280 °C 540 °F
Melting Onset (Solidus)
180 °C 360 °F
Specific Heat Capacity
150 J/kg-K 0.035 BTU/lb-°F
Thermal Conductivity
37 W/m-K 21 BTU/h-ft-°F
Thermal Expansion
28 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
8.7 % IACS
Electrical Conductivity: Equal Weight (Specific)
7.5 % IACS
Otherwise Unclassified Properties
Base Metal Price
85 % relative
Density
11 g/cm3 660 lb/ft3
Embodied Carbon
6.1 kg CO2/kg material
Embodied Energy
100 MJ/kg 44 x 103 BTU/lb
Embodied Water
610 L/kg 73 gal/lb
Common Calculations
Stiffness to Weight: Axial
1.2 points
Stiffness to Weight: Bending
9.0 points
Strength to Weight: Axial
0.88 points
Strength to Weight: Bending
2.2 points
Thermal Diffusivity
24 mm2/s
Thermal Shock Resistance
3.7 points
Alloy Composition
| Pb | 78.4 to 80.5 | |
| Sn | 19.5 to 20.5 | |
| Sb | 0 to 0.5 | |
| Bi | 0 to 0.25 | |
| Ag | 0 to 0.1 | |
| In | 0 to 0.1 | |
| Cu | 0 to 0.080 | |
| Au | 0 to 0.050 | |
| As | 0 to 0.030 | |
| Fe | 0 to 0.020 | |
| Ni | 0 to 0.010 | |
| Cd | 0 to 0.0050 | |
| Al | 0 to 0.0010 | |
| Zn | 0 to 0.0010 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
ISO 9453: Soft solder alloys - Chemical compositions and forms