MakeItFrom.com
Menu (ESC)

SAE-AISI 1118 Steel vs. SAE-AISI 4118 Steel

Both SAE-AISI 1118 steel and SAE-AISI 4118 steel are iron alloys. They have a very high 99% of their average alloy composition in common.

For each property being compared, the top bar is SAE-AISI 1118 steel and the bottom bar is SAE-AISI 4118 steel.

Metric UnitsUS Customary Units

Mechanical Properties

Brinell Hardness 140
150
Elastic (Young's, Tensile) Modulus, GPa 190
190
Elongation at Break, % 13
23
Fatigue Strength, MPa 260
230
Poisson's Ratio 0.29
0.29
Shear Modulus, GPa 73
73
Shear Strength, MPa 300
320
Tensile Strength: Ultimate (UTS), MPa 490
500
Tensile Strength: Yield (Proof), MPa 410
320

Thermal Properties

Latent Heat of Fusion, J/g 250
250
Maximum Temperature: Mechanical, °C 400
410
Melting Completion (Liquidus), °C 1460
1460
Melting Onset (Solidus), °C 1420
1420
Specific Heat Capacity, J/kg-K 470
470
Thermal Conductivity, W/m-K 52
46
Thermal Expansion, µm/m-K 12
13

Electrical Properties

Electrical Conductivity: Equal Volume, % IACS 7.1
7.2
Electrical Conductivity: Equal Weight (Specific), % IACS 8.1
8.2

Otherwise Unclassified Properties

Base Metal Price, % relative 1.9
2.3
Density, g/cm3 7.8
7.8
Embodied Carbon, kg CO2/kg material 1.4
1.5
Embodied Energy, MJ/kg 19
20
Embodied Water, L/kg 47
49

Common Calculations

Resilience: Ultimate (Unit Rupture Work), MJ/m3 61
100
Resilience: Unit (Modulus of Resilience), kJ/m3 450
280
Stiffness to Weight: Axial, points 13
13
Stiffness to Weight: Bending, points 24
24
Strength to Weight: Axial, points 17
18
Strength to Weight: Bending, points 18
18
Thermal Diffusivity, mm2/s 14
13
Thermal Shock Resistance, points 15
15

Alloy Composition

Carbon (C), % 0.14 to 0.2
0.18 to 0.23
Chromium (Cr), % 0
0.4 to 0.6
Iron (Fe), % 98 to 98.5
97.5 to 98.4
Manganese (Mn), % 1.3 to 1.6
0.7 to 0.9
Molybdenum (Mo), % 0
0.2 to 0.3
Phosphorus (P), % 0 to 0.040
0 to 0.035
Silicon (Si), % 0
0.15 to 0.35
Sulfur (S), % 0.080 to 0.13
0 to 0.040