SAE-AISI 4720 Steel vs. SAE-AISI 1345 Steel
Both SAE-AISI 4720 steel and SAE-AISI 1345 steel are iron alloys. They have a very high 98% of their average alloy composition in common.
For each property being compared, the top bar is SAE-AISI 4720 steel and the bottom bar is SAE-AISI 1345 steel.
Metric UnitsUS Customary Units
Mechanical Properties
Brinell Hardness | 150 | |
170 to 210 |
Elastic (Young's, Tensile) Modulus, GPa | 190 | |
190 |
Elongation at Break, % | 25 | |
11 to 23 |
Fatigue Strength, MPa | 260 | |
230 to 390 |
Poisson's Ratio | 0.29 | |
0.29 |
Shear Modulus, GPa | 73 | |
72 |
Shear Strength, MPa | 310 | |
370 to 440 |
Tensile Strength: Ultimate (UTS), MPa | 490 | |
590 to 730 |
Tensile Strength: Yield (Proof), MPa | 350 | |
330 to 620 |
Thermal Properties
Latent Heat of Fusion, J/g | 250 | |
250 |
Maximum Temperature: Mechanical, °C | 410 | |
400 |
Melting Completion (Liquidus), °C | 1460 | |
1450 |
Melting Onset (Solidus), °C | 1420 | |
1410 |
Specific Heat Capacity, J/kg-K | 470 | |
470 |
Thermal Conductivity, W/m-K | 39 | |
51 |
Thermal Expansion, µm/m-K | 13 | |
12 |
Electrical Properties
Electrical Conductivity: Equal Volume, % IACS | 7.3 | |
7.2 |
Electrical Conductivity: Equal Weight (Specific), % IACS | 8.4 | |
8.3 |
Otherwise Unclassified Properties
Base Metal Price, % relative | 2.9 | |
1.9 |
Density, g/cm3 | 7.9 | |
7.8 |
Embodied Carbon, kg CO2/kg material | 1.6 | |
1.4 |
Embodied Energy, MJ/kg | 21 | |
19 |
Embodied Water, L/kg | 50 | |
48 |
Common Calculations
Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 110 | |
78 to 120 |
Resilience: Unit (Modulus of Resilience), kJ/m3 | 330 | |
290 to 1040 |
Stiffness to Weight: Axial, points | 13 | |
13 |
Stiffness to Weight: Bending, points | 24 | |
24 |
Strength to Weight: Axial, points | 17 | |
21 to 26 |
Strength to Weight: Bending, points | 18 | |
20 to 23 |
Thermal Diffusivity, mm2/s | 10 | |
14 |
Thermal Shock Resistance, points | 14 | |
19 to 23 |
Alloy Composition
Carbon (C), % | 0.17 to 0.22 | |
0.43 to 0.48 |
Chromium (Cr), % | 0.35 to 0.55 | |
0 |
Iron (Fe), % | 96.7 to 97.8 | |
97.2 to 97.8 |
Manganese (Mn), % | 0.5 to 0.7 | |
1.6 to 1.9 |
Molybdenum (Mo), % | 0.15 to 0.25 | |
0 |
Nickel (Ni), % | 0.9 to 1.2 | |
0 |
Phosphorus (P), % | 0 to 0.035 | |
0 to 0.035 |
Silicon (Si), % | 0.15 to 0.35 | |
0.15 to 0.35 |
Sulfur (S), % | 0 to 0.040 | |
0 to 0.040 |