Thermal conductivity against densityHigher and further left: spreads more heat for its weightThermal expansion against thermal conductivityLower and further right: warps less when heated
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Sources4 documents: Copper Development Association, Cleveland-Cliffs, Wieland, Steel Construction Institute
Brass C360
C36000 free-cutting brass, H02 half-hard rod 1 in. section (20% cold work), copper.org typical values
Stainless Steel 304
Type 304, annealed flat-rolled (Cleveland-Cliffs 304/304L Product Data Bulletin, May 2021); Poisson's ratio from the Nickel Institute/SCI structural stainless design manual
304/304L Stainless Steel Product Data Bulletin (2021)Cleveland-CliffsStainless Steel 304 · Yield strength: typical, annealed, 70 °F (21 °C)Stainless Steel 304 · Ultimate tensile strength: typical, annealed, 70 °F (21 °C)Stainless Steel 304 · Elongation at break: typical, annealed, in 2 in. (50.8 mm)Stainless Steel 304 · Young's modulus (stiffness): typical, in tensionStainless Steel 304 · Density: typicalStainless Steel 304 · Thermal conductivity: at 100 °CStainless Steel 304 · Thermal expansion: mean, 0–100 °CStainless Steel 304 · Specific heat: mean, 0–100 °CStainless Steel 304 · Melting point: melting rangeStainless Steel 304 · Max service temperature: continuous, oxidation (scaling) limit in air
3
Wieland-Z30 (CuZn39Pb2, C37700) Data SheetWielandarchived copyBrass C360 · Poisson's ratio: base material: leaded free-machining brass CuZn39Pb2 (C37700), Wieland-Z30 rolled products, reference value at room temperature
4
Design Manual for Structural Stainless Steel, 4th Edition (P413)Steel Construction Institutearchived copyStainless Steel 304 · Poisson's ratio: design value (structural stainless steels)
Each number points to the document that states it, with the exact basis. Values without a number are computed from the sourced ones. "Not sourced" means no citable source states it (or only a specification minimum); figures computed from it are left out too.
Questions
Mechanical
Is Brass C360 stronger than Stainless Steel 304?
Brass C360 is stronger: its yield strength is 310 MPa against 241 MPa for Stainless Steel 304 (29%).
Which is lighter, Brass C360 or Stainless Steel 304?
Stainless Steel 304 is lighter: 8,030 kg/m³ against 8,498 kg/m³ for Brass C360.
Which is stiffer, Brass C360 or Stainless Steel 304?
Stainless Steel 304 is stiffer: Young's modulus 193 GPa against 96.5 GPa for Brass C360, so the same part in Stainless Steel 304 deflects less under the same load.
Which is lighter for the same job, Brass C360 or Stainless Steel 304?
For the same stiffness or strength: Brass C360 is lighter for a strong rod or tie, strong beam, strong panel or plate; Stainless Steel 304 is lighter for a stiff rod or tie (tension), stiff beam (bending), stiff panel or plate.
Part that must be
Brass C360
Stainless Steel 304
Stiff rod or tie (tension)
2.12x heavier
lighter
Stiff beam (bending)
50% heavier
lighter
Stiff panel or plate
33% heavier
lighter
Strong rod or tie
lighter
22% heavier
Strong beam
lighter
12% heavier
Strong panel or plate
lighter
7% 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, Brass C360 or Stainless Steel 304?
Stainless Steel 304 stretches further before it breaks: 55% elongation at break against 25% for Brass C360.
Thermal
Which conducts heat better, Brass C360 or Stainless Steel 304?
Brass C360 conducts heat better: 116 W/m·K against 16.2 W/m·K for Stainless Steel 304.
Which expands less with temperature?
Stainless Steel 304 expands less: 16.9 µm/m·K against 20.5 µm/m·K for Brass C360.