SAC305 (Sn96.5Ag3.0Cu0.5) solder alloy, bulk; Indium Corporation Indalloy 256 (SAC305) for Preforms product data sheet (Form No. 100346 R0, 2024), selected properties, test temperature not stated; expansion and specific heat from MacDermid Alpha VACULOY SAC TDS (06 September 2023).
Every value links to the document that states it. "Not sourced" means no citable source states it (or only a specification minimum); figures computed from it are left out too.
Questions
Is Solder SAC305 stronger than Steel AISI 4340?
Steel AISI 4340 is stronger: its yield strength is 1,035 MPa against 22 MPa for Solder SAC305 (47x).
Which is lighter, Solder SAC305 or Steel AISI 4340?
Solder SAC305 is lighter: 7,350 kg/m³ against 7,840 kg/m³ for Steel AISI 4340.
Which is stiffer, Solder SAC305 or Steel AISI 4340?
Steel AISI 4340 is stiffer: Young's modulus 200 GPa against 6.9 GPa for Solder SAC305, so the same part in Steel AISI 4340 deflects less under the same load.
Which is lighter for the same job, Solder SAC305 or Steel AISI 4340?
For the same stiffness or strength: Steel AISI 4340 is lighter for a stiff rod or tie (tension), stiff beam (bending), stiff panel or plate, strong rod or tie, strong beam, strong panel or plate.
Part that must be
Solder SAC305
Steel AISI 4340
Stiff rod or tie (tension)
27.2x heavier
lighter
Stiff beam (bending)
5.05x heavier
lighter
Stiff panel or plate
2.88x heavier
lighter
Strong rod or tie
44.1x heavier
lighter
Strong beam
12.2x heavier
lighter
Strong panel or plate
6.43x heavier
lighter
For the same stiffness or strength, mass scales with density over stiffness (or strength) raised to a power set by how the part is loaded: 1 for a rod in tension, 1/2 for a beam in bending, 1/3 for a panel (the standard material-selection indices).
Which conducts heat better, Solder SAC305 or Steel AISI 4340?
Solder SAC305 conducts heat better: 61 W/m·K against 37.5 W/m·K for Steel AISI 4340.
Which expands less with temperature?
Steel AISI 4340 expands less: 11.3 µm/m·K against 21.9 µm/m·K for Solder SAC305.