MakeItFrom.com
Menu (ESC)

Hardened AISI 440A vs. Hardened SAE-AISI A7

Both hardened AISI 440A and hardened SAE-AISI A7 are iron alloys. Both are furnished in the hardened (H) condition. They have 88% of their average alloy composition in common. There are 22 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 hardened AISI 440A and the bottom bar is hardened SAE-AISI A7.

Metric UnitsUS Customary Units

Mechanical Properties

Elastic (Young's, Tensile) Modulus, GPa 200
190
Poisson's Ratio 0.28
0.29
Shear Modulus, GPa 77
72
Tensile Strength: Ultimate (UTS), MPa 1790
2150

Thermal Properties

Latent Heat of Fusion, J/g 280
260
Melting Completion (Liquidus), °C 1480
1470
Melting Onset (Solidus), °C 1370
1430
Specific Heat Capacity, J/kg-K 480
470
Thermal Conductivity, W/m-K 23
37
Thermal Expansion, µm/m-K 10
12

Otherwise Unclassified Properties

Base Metal Price, % relative 9.0
10
Density, g/cm3 7.7
7.7
Embodied Carbon, kg CO2/kg material 2.2
13
Embodied Energy, MJ/kg 31
200
Embodied Water, L/kg 120
100

Common Calculations

PREN (Pitting Resistance) 18
11
Stiffness to Weight: Axial, points 14
13
Stiffness to Weight: Bending, points 25
25
Strength to Weight: Axial, points 65
77
Strength to Weight: Bending, points 43
48
Thermal Diffusivity, mm2/s 6.2
10
Thermal Shock Resistance, points 65
72

Alloy Composition

Carbon (C), % 0.6 to 0.75
2.0 to 2.9
Chromium (Cr), % 16 to 18
5.0 to 5.8
Copper (Cu), % 0
0 to 0.25
Iron (Fe), % 78.4 to 83.4
81.4 to 87.7
Manganese (Mn), % 0 to 1.0
0 to 0.8
Molybdenum (Mo), % 0 to 0.75
0.9 to 1.4
Nickel (Ni), % 0
0 to 0.3
Phosphorus (P), % 0 to 0.040
0 to 0.030
Silicon (Si), % 0 to 1.0
0 to 0.5
Sulfur (S), % 0 to 0.015
0 to 0.030
Tungsten (W), % 0
0.5 to 1.5
Vanadium (V), % 0
3.9 to 5.2