MakeItFrom.com
Menu (ESC)

R30021 Cobalt vs. S31266 Stainless Steel

R30021 cobalt belongs to the cobalt alloys classification, while S31266 stainless steel belongs to the iron alloys. They have a modest 34% of their average alloy composition in common, which, by itself, doesn't mean much. There are 27 material properties with values for both materials. Properties with values for just one material (8, in this case) are not shown.

For each property being compared, the top bar is R30021 cobalt and the bottom bar is S31266 stainless steel.

Metric UnitsUS Customary Units

Mechanical Properties

Elastic (Young's, Tensile) Modulus, GPa 220
210
Elongation at Break, % 9.0
40
Fatigue Strength, MPa 250
400
Poisson's Ratio 0.29
0.28
Shear Modulus, GPa 86
81
Tensile Strength: Ultimate (UTS), MPa 700
860
Tensile Strength: Yield (Proof), MPa 500
470

Thermal Properties

Latent Heat of Fusion, J/g 330
310
Melting Completion (Liquidus), °C 1350
1470
Melting Onset (Solidus), °C 1190
1420
Specific Heat Capacity, J/kg-K 450
460
Thermal Conductivity, W/m-K 15
12
Thermal Expansion, µm/m-K 11
16

Electrical Properties

Electrical Conductivity: Equal Volume, % IACS 1.9
1.8
Electrical Conductivity: Equal Weight (Specific), % IACS 2.1
2.0

Otherwise Unclassified Properties

Density, g/cm3 8.4
8.2
Embodied Carbon, kg CO2/kg material 8.0
6.5
Embodied Energy, MJ/kg 110
89
Embodied Water, L/kg 520
220

Common Calculations

Resilience: Ultimate (Unit Rupture Work), MJ/m3 57
290
Resilience: Unit (Modulus of Resilience), kJ/m3 570
540
Stiffness to Weight: Axial, points 15
14
Stiffness to Weight: Bending, points 24
24
Strength to Weight: Axial, points 23
29
Strength to Weight: Bending, points 21
24
Thermal Diffusivity, mm2/s 3.8
3.1
Thermal Shock Resistance, points 21
18

Alloy Composition

Carbon (C), % 0.2 to 0.35
0 to 0.030
Chromium (Cr), % 26 to 29
23 to 25
Cobalt (Co), % 61.7 to 67.3
0
Copper (Cu), % 0
1.0 to 2.5
Iron (Fe), % 0 to 3.0
34.1 to 46
Manganese (Mn), % 0
2.0 to 4.0
Molybdenum (Mo), % 4.5 to 6.0
5.2 to 6.2
Nickel (Ni), % 2.0 to 3.0
21 to 24
Nitrogen (N), % 0
0.35 to 0.6
Phosphorus (P), % 0
0 to 0.035
Silicon (Si), % 0 to 1.5
0 to 1.0
Sulfur (S), % 0
0 to 0.020
Tungsten (W), % 0
1.5 to 2.5