MakeItFrom.com
Menu (ESC)

R30006 Cobalt vs. S21900 Stainless Steel

R30006 cobalt belongs to the cobalt alloys classification, while S21900 stainless steel belongs to the iron alloys. They have a modest 24% 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 (10, in this case) are not shown.

For each property being compared, the top bar is R30006 cobalt and the bottom bar is S21900 stainless steel.

Metric UnitsUS Customary Units

Mechanical Properties

Elastic (Young's, Tensile) Modulus, GPa 220
200
Elongation at Break, % 1.0
50
Fatigue Strength, MPa 260
380
Poisson's Ratio 0.28
0.28
Shear Modulus, GPa 85
78
Tensile Strength: Ultimate (UTS), MPa 900
710
Tensile Strength: Yield (Proof), MPa 540
390

Thermal Properties

Latent Heat of Fusion, J/g 320
290
Melting Completion (Liquidus), °C 1400
1400
Melting Onset (Solidus), °C 1290
1350
Specific Heat Capacity, J/kg-K 450
480
Thermal Conductivity, W/m-K 15
14
Thermal Expansion, µm/m-K 11
17

Electrical Properties

Electrical Conductivity: Equal Volume, % IACS 1.6
2.5
Electrical Conductivity: Equal Weight (Specific), % IACS 1.7
2.9

Otherwise Unclassified Properties

Density, g/cm3 8.6
7.7
Embodied Carbon, kg CO2/kg material 7.8
3.0
Embodied Energy, MJ/kg 110
43
Embodied Water, L/kg 500
160

Common Calculations

Resilience: Ultimate (Unit Rupture Work), MJ/m3 7.8
300
Resilience: Unit (Modulus of Resilience), kJ/m3 670
380
Stiffness to Weight: Axial, points 14
14
Stiffness to Weight: Bending, points 23
25
Strength to Weight: Axial, points 29
26
Strength to Weight: Bending, points 24
23
Thermal Diffusivity, mm2/s 3.9
3.8
Thermal Shock Resistance, points 26
15

Alloy Composition

Carbon (C), % 0.9 to 1.4
0 to 0.080
Chromium (Cr), % 27 to 32
19 to 21.5
Cobalt (Co), % 48.6 to 68.1
0
Iron (Fe), % 0 to 3.0
59.4 to 67.4
Manganese (Mn), % 0
8.0 to 10
Molybdenum (Mo), % 0 to 1.0
0
Nickel (Ni), % 0 to 3.0
5.5 to 7.5
Nitrogen (N), % 0
0.15 to 0.4
Phosphorus (P), % 0
0 to 0.045
Silicon (Si), % 0 to 2.0
0 to 1.0
Sulfur (S), % 0
0 to 0.030
Tungsten (W), % 4.0 to 6.0
0