MakeItFrom.com
Menu (ESC)

SAE-AISI 4320 Steel vs. R30021 Cobalt

SAE-AISI 4320 steel belongs to the iron alloys classification, while R30021 cobalt belongs to the cobalt alloys. There are 27 material properties with values for both materials. Properties with values for just one material (6, in this case) are not shown.

For each property being compared, the top bar is SAE-AISI 4320 steel and the bottom bar is R30021 cobalt.

Metric UnitsUS Customary Units

Mechanical Properties

Elastic (Young's, Tensile) Modulus, GPa 190
220
Elongation at Break, % 21 to 29
9.0
Fatigue Strength, MPa 320
250
Poisson's Ratio 0.29
0.29
Shear Modulus, GPa 73
86
Tensile Strength: Ultimate (UTS), MPa 570 to 790
700
Tensile Strength: Yield (Proof), MPa 430 to 460
500

Thermal Properties

Latent Heat of Fusion, J/g 250
330
Melting Completion (Liquidus), °C 1460
1350
Melting Onset (Solidus), °C 1420
1190
Specific Heat Capacity, J/kg-K 470
450
Thermal Conductivity, W/m-K 46
15
Thermal Expansion, µm/m-K 11
11

Electrical Properties

Electrical Conductivity: Equal Volume, % IACS 7.4
1.9
Electrical Conductivity: Equal Weight (Specific), % IACS 8.5
2.1

Otherwise Unclassified Properties

Density, g/cm3 7.9
8.4
Embodied Carbon, kg CO2/kg material 1.7
8.0
Embodied Energy, MJ/kg 22
110
Embodied Water, L/kg 52
520

Common Calculations

Resilience: Ultimate (Unit Rupture Work), MJ/m3 140 to 150
57
Resilience: Unit (Modulus of Resilience), kJ/m3 480 to 560
570
Stiffness to Weight: Axial, points 13
15
Stiffness to Weight: Bending, points 24
24
Strength to Weight: Axial, points 20 to 28
23
Strength to Weight: Bending, points 19 to 24
21
Thermal Diffusivity, mm2/s 13
3.8
Thermal Shock Resistance, points 19 to 27
21

Alloy Composition

Carbon (C), % 0.17 to 0.22
0.2 to 0.35
Chromium (Cr), % 0.4 to 0.6
26 to 29
Cobalt (Co), % 0
61.7 to 67.3
Iron (Fe), % 95.8 to 97
0 to 3.0
Manganese (Mn), % 0.45 to 0.65
0
Molybdenum (Mo), % 0.2 to 0.3
4.5 to 6.0
Nickel (Ni), % 1.7 to 2.0
2.0 to 3.0
Phosphorus (P), % 0 to 0.035
0
Silicon (Si), % 0.15 to 0.35
0 to 1.5
Sulfur (S), % 0 to 0.040
0