300°Csourceproducer's maximum application temperature (optical components)
Values for
1100-O (annealed) commercially pure aluminium, Kaiser Aluminum Tube & Pipe Alloy 1100 Technical Data (Rev. 05/06), typical properties; specific heat from Hydro EN AW-1050A (99.5% Al) extruded-products datasheet (10/2018).
Synthetic single-crystal silicon (cubic, diamond structure), Korth Kristalle (crystal grower) material data; Korth usually supplies Floating Zone (FZ) material, Czochralski (Cz) also offered. Silicon is elastically anisotropic; the producer quotes one modulus and the solver is isotropic.
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 Aluminum 1100-O stronger than Silicon?
Silicon is stronger: its tensile strength is 130 MPa against yield strength 35 MPa for Aluminum 1100-O (3.71x).
Which is lighter, Aluminum 1100-O or Silicon?
Silicon is lighter: 2,329 kg/m³ against 2,710 kg/m³ for Aluminum 1100-O.
Which is stiffer, Aluminum 1100-O or Silicon?
Silicon is stiffer: Young's modulus 131 GPa against 69 GPa for Aluminum 1100-O, so the same part in Silicon deflects less under the same load.
Which is lighter for the same job, Aluminum 1100-O or Silicon?
For the same stiffness or strength: Silicon 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
Aluminum 1100-O
Silicon
Stiff rod or tie (tension)
2.21x heavier
lighter
Stiff beam (bending)
1.6x heavier
lighter
Stiff panel or plate
44% heavier
lighter
Strong rod or tie
4.32x heavier
lighter
Strong beam
2.79x heavier
lighter
Strong panel or plate
2.24x 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, Aluminum 1100-O or Silicon?
Aluminum 1100-O conducts heat better: 222 W/m·K against 163 W/m·K for Silicon.
Which expands less with temperature?
Silicon expands less: 2.62 µm/m·K against 23.6 µm/m·K for Aluminum 1100-O.