Solder Alloy 121 vs. SAE-AISI 8740 Steel
Solder alloy 121 belongs to the otherwise unclassified metals classification, while SAE-AISI 8740 steel belongs to the iron alloys. There are 25 material properties with values for both materials. Properties with values for just one material (6, in this case) are not shown.
For each property being compared, the top bar is solder alloy 121 and the bottom bar is SAE-AISI 8740 steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 11 | |
| 170 to 200 |
| Elastic (Young's, Tensile) Modulus, GPa | 21 | |
| 190 |
| Elongation at Break, % | 25 | |
| 11 to 23 |
| Poisson's Ratio | 0.43 | |
| 0.29 |
| Shear Modulus, GPa | 7.5 | |
| 73 |
| Tensile Strength: Ultimate (UTS), MPa | 32 | |
| 580 to 670 |
Thermal Properties
| Latent Heat of Fusion, J/g | 29 | |
| 250 |
| Melting Completion (Liquidus), °C | 290 | |
| 1460 |
| Melting Onset (Solidus), °C | 230 | |
| 1420 |
| Specific Heat Capacity, J/kg-K | 140 | |
| 470 |
| Thermal Conductivity, W/m-K | 31 | |
| 39 |
| Thermal Expansion, µm/m-K | 28 | |
| 13 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 8.8 | |
| 7.3 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 7.4 | |
| 8.4 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 80 | |
| 2.6 |
| Density, g/cm3 | 11 | |
| 7.8 |
| Embodied Carbon, kg CO2/kg material | 5.6 | |
| 1.5 |
| Embodied Energy, MJ/kg | 93 | |
| 20 |
| Embodied Water, L/kg | 580 | |
| 50 |
Common Calculations
| Stiffness to Weight: Axial, points | 1.1 | |
| 13 |
| Stiffness to Weight: Bending, points | 8.6 | |
| 24 |
| Strength to Weight: Axial, points | 0.84 | |
| 20 to 24 |
| Strength to Weight: Bending, points | 2.1 | |
| 20 to 22 |
| Thermal Diffusivity, mm2/s | 20 | |
| 10 |
| Thermal Shock Resistance, points | 3.9 | |
| 17 to 20 |
Alloy Composition
| Aluminum (Al), % | 0 to 0.0010 | |
| 0 |
| Antimony (Sb), % | 0 to 0.5 | |
| 0 |
| Arsenic (As), % | 0 to 0.030 | |
| 0 |
| Bismuth (Bi), % | 0 to 0.25 | |
| 0 |
| Cadmium (Cd), % | 0 to 0.0050 | |
| 0 |
| Carbon (C), % | 0 | |
| 0.38 to 0.43 |
| Chromium (Cr), % | 0 | |
| 0.4 to 0.6 |
| Copper (Cu), % | 0 to 0.080 | |
| 0 |
| Gold (Au), % | 0 to 0.050 | |
| 0 |
| Indium (In), % | 0 to 0.1 | |
| 0 |
| Iron (Fe), % | 0 to 0.020 | |
| 96.5 to 97.7 |
| Lead (Pb), % | 83.4 to 85.5 | |
| 0 |
| Manganese (Mn), % | 0 | |
| 0.75 to 1.0 |
| Molybdenum (Mo), % | 0 | |
| 0.2 to 0.3 |
| Nickel (Ni), % | 0 to 0.010 | |
| 0.4 to 0.7 |
| Phosphorus (P), % | 0 | |
| 0 to 0.035 |
| Silicon (Si), % | 0 | |
| 0.15 to 0.35 |
| Silver (Ag), % | 0 to 0.1 | |
| 0 |
| Sulfur (S), % | 0 | |
| 0 to 0.040 |
| Tin (Sn), % | 14.5 to 15.5 | |
| 0 |
| Zinc (Zn), % | 0 to 0.0010 | |
| 0 |