Solder Alloy 121 vs. SAE-AISI M4 Steel
Solder alloy 121 belongs to the otherwise unclassified metals classification, while SAE-AISI M4 steel belongs to the iron alloys. There are 21 material properties with values for both materials. Properties with values for just one material (5, 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 M4 steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 21 | |
| 200 |
| Poisson's Ratio | 0.43 | |
| 0.29 |
| Shear Modulus, GPa | 7.5 | |
| 76 |
| Tensile Strength: Ultimate (UTS), MPa | 32 | |
| 770 to 2150 |
Thermal Properties
| Latent Heat of Fusion, J/g | 29 | |
| 260 |
| Melting Completion (Liquidus), °C | 290 | |
| 1610 |
| Melting Onset (Solidus), °C | 230 | |
| 1560 |
| Specific Heat Capacity, J/kg-K | 140 | |
| 440 |
| Thermal Conductivity, W/m-K | 31 | |
| 25 |
| Thermal Expansion, µm/m-K | 28 | |
| 12 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 80 | |
| 25 |
| Density, g/cm3 | 11 | |
| 8.3 |
| Embodied Carbon, kg CO2/kg material | 5.6 | |
| 14 |
| Embodied Energy, MJ/kg | 93 | |
| 210 |
| Embodied Water, L/kg | 580 | |
| 110 |
Common Calculations
| Stiffness to Weight: Axial, points | 1.1 | |
| 13 |
| Stiffness to Weight: Bending, points | 8.6 | |
| 23 |
| Strength to Weight: Axial, points | 0.84 | |
| 26 to 72 |
| Strength to Weight: Bending, points | 2.1 | |
| 23 to 45 |
| Thermal Diffusivity, mm2/s | 20 | |
| 6.9 |
| Thermal Shock Resistance, points | 3.9 | |
| 24 to 68 |
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 | |
| 1.3 to 1.4 |
| Chromium (Cr), % | 0 | |
| 3.8 to 4.8 |
| Copper (Cu), % | 0 to 0.080 | |
| 0 to 0.25 |
| Gold (Au), % | 0 to 0.050 | |
| 0 |
| Indium (In), % | 0 to 0.1 | |
| 0 |
| Iron (Fe), % | 0 to 0.020 | |
| 75.9 to 81.4 |
| Lead (Pb), % | 83.4 to 85.5 | |
| 0 |
| Manganese (Mn), % | 0 | |
| 0.15 to 0.4 |
| Molybdenum (Mo), % | 0 | |
| 4.3 to 5.5 |
| Nickel (Ni), % | 0 to 0.010 | |
| 0 to 0.3 |
| Phosphorus (P), % | 0 | |
| 0 to 0.030 |
| Silicon (Si), % | 0 | |
| 0.2 to 0.45 |
| Silver (Ag), % | 0 to 0.1 | |
| 0 |
| Sulfur (S), % | 0 | |
| 0 to 0.030 |
| Tin (Sn), % | 14.5 to 15.5 | |
| 0 |
| Tungsten (W), % | 0 | |
| 5.3 to 6.5 |
| Vanadium (V), % | 0 | |
| 3.8 to 4.5 |
| Zinc (Zn), % | 0 to 0.0010 | |
| 0 |