SAE-AISI 9255 Steel vs. SAE-AISI 8630 Steel
Both SAE-AISI 9255 steel and SAE-AISI 8630 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 9255 steel and the bottom bar is SAE-AISI 8630 steel.
Metric UnitsUS Customary Units
Mechanical Properties
Brinell Hardness | 200 | |
160 to 200 |
Elastic (Young's, Tensile) Modulus, GPa | 190 | |
190 |
Elongation at Break, % | 21 | |
12 to 24 |
Fatigue Strength, MPa | 270 | |
260 to 350 |
Poisson's Ratio | 0.29 | |
0.29 |
Shear Modulus, GPa | 72 | |
73 |
Shear Strength, MPa | 430 | |
340 to 410 |
Tensile Strength: Ultimate (UTS), MPa | 680 | |
540 to 680 |
Tensile Strength: Yield (Proof), MPa | 390 | |
360 to 560 |
Thermal Properties
Latent Heat of Fusion, J/g | 280 | |
250 |
Maximum Temperature: Mechanical, °C | 400 | |
410 |
Melting Completion (Liquidus), °C | 1430 | |
1460 |
Melting Onset (Solidus), °C | 1390 | |
1420 |
Specific Heat Capacity, J/kg-K | 480 | |
470 |
Thermal Conductivity, W/m-K | 46 | |
39 |
Thermal Expansion, µm/m-K | 13 | |
11 |
Electrical Properties
Electrical Conductivity: Equal Volume, % IACS | 7.4 | |
7.3 |
Electrical Conductivity: Equal Weight (Specific), % IACS | 8.6 | |
8.3 |
Otherwise Unclassified Properties
Base Metal Price, % relative | 2.0 | |
2.6 |
Density, g/cm3 | 7.7 | |
7.8 |
Embodied Carbon, kg CO2/kg material | 1.5 | |
1.5 |
Embodied Energy, MJ/kg | 20 | |
20 |
Embodied Water, L/kg | 46 | |
50 |
Common Calculations
Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 120 | |
78 to 110 |
Resilience: Unit (Modulus of Resilience), kJ/m3 | 400 | |
340 to 840 |
Stiffness to Weight: Axial, points | 13 | |
13 |
Stiffness to Weight: Bending, points | 25 | |
24 |
Strength to Weight: Axial, points | 24 | |
19 to 24 |
Strength to Weight: Bending, points | 22 | |
19 to 22 |
Thermal Diffusivity, mm2/s | 13 | |
10 |
Thermal Shock Resistance, points | 21 | |
18 to 23 |
Alloy Composition
Carbon (C), % | 0.51 to 0.59 | |
0.28 to 0.33 |
Chromium (Cr), % | 0 | |
0.4 to 0.6 |
Iron (Fe), % | 96.2 to 97 | |
96.8 to 97.9 |
Manganese (Mn), % | 0.7 to 1.0 | |
0.7 to 0.9 |
Molybdenum (Mo), % | 0 | |
0.15 to 0.25 |
Nickel (Ni), % | 0 | |
0.4 to 0.7 |
Phosphorus (P), % | 0 to 0.035 | |
0 to 0.035 |
Silicon (Si), % | 1.8 to 2.2 | |
0.15 to 0.35 |
Sulfur (S), % | 0 to 0.040 | |
0 to 0.040 |