Rubber vs. Solder SAC305

Compare Rubber vs. Solder SAC305 strength, stiffness, weight and thermal properties.

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RubberBulk polymer (molded or machined)

Mechanical
Try it on a partA bracket to run stress or thermal on, free in your browser	Open in LessCAD	Open in LessCAD
Yield strength	not given (tensile used)	22MPasourcetypical
Ultimate tensile strength	23MPasourcetypical	39.6MPasourcetypical1.72x stronger
Elongation at break	830%sourcetypical16.9x more ductile	49%sourcetypical
Young's modulus (stiffness)	not sourced	6.9GPasourcetypical, temperature and strain rate not stated
Density	960kg/m³sourcetypical (specific gravity)	7,350kg/m³sourcetypical
Strength to weight	24kN·m/kg8x higher	2.99kN·m/kg
Stiffness to weight	not sourced	0.939MN·m/kg
Poisson's ratio	0.5sourcegovernment (NBS J. Res. 68A, 1964): computed by NBS for peroxide-cured gum NR vulcanizate, 25 °C, infinitesimal deformation0.49 in the solver: the linear element locks as the ratio nears 0.5 (nearly incompressible).	0.35sourcetypical
Shear modulus	not sourced	2.56GPa
Bulk modulus	not sourced	7.67GPa
Speed of sound	not sourced	969m/s
Thermal
Thermal conductivity	0.151W/m·Ksourcegovernment selected value (US Army Natick Laboratories TR 66-49-PR, 1966), soft vulcanized natural rubber, 25 °C	61W/m·Ksourcetypical, temperature not stated
Thermal expansion	not sourced	21.9µm/m·Ksourcemean, 20-100 °C (MacDermid Alpha)
100 mm part over a 50 °C swing	not sourced	110µm growth
Specific heat	1,881J/kg·Ksourcegovernment (NBS J. Res. 68A, Table 7; values observed for unvulcanized NR by Bekkedahl and Matheson), 25 °C	232J/kg·Ksourcetypical (MacDermid Alpha)
Heats up and cools (diffusivity)	0.0836mm²/s	35.8mm²/s428x faster
Thermal shock resistance	not sourced	5,773W/m
Melting point	not sourced	217–220°Csourcesolidus-liquidus
Max service temperature	70°Csourcecontinuous use operating range	not sourced
Values for	Weir Minerals Linatex Premium rubber (95 % natural rubber), typical physical properties, spec sheet WMD0118/202305	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 Rubber stronger than Solder SAC305?

Rubber is stronger: its tensile strength is 23 MPa against yield strength 22 MPa for Solder SAC305 (5%).

Which is lighter, Rubber or Solder SAC305?

Rubber is lighter: 960 kg/m³ against 7,350 kg/m³ for Solder SAC305.

Which is lighter for the same job, Rubber or Solder SAC305?

For the same stiffness or strength: Rubber is lighter for a strong rod or tie, strong beam, strong panel or plate.

Part that must be	Rubber	Solder SAC305
Strong rod or tie	lighter	8x heavier
Strong beam	lighter	7.89x heavier
Strong panel or plate	lighter	7.83x heavier

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 is more ductile, Rubber or Solder SAC305?

Rubber stretches further before it breaks: 830% elongation at break against 49% for Solder SAC305.

Which conducts heat better, Rubber or Solder SAC305?

Solder SAC305 conducts heat better: 61 W/m·K against 0.151 W/m·K for Rubber.

Among 72 materials

Stiffness against density

Strength against density