AISI 321H Stainless Steel vs. ASTM A387 Grade 21 Steel
Both AISI 321H stainless steel and ASTM A387 grade 21 steel are iron alloys. They have 74% of their average alloy composition in common. There are 32 material properties with values for both materials. Properties with values for just one material (3, in this case) are not shown.
For each property being compared, the top bar is AISI 321H stainless steel and the bottom bar is ASTM A387 grade 21 steel.
Metric UnitsUS Customary Units
Mechanical Properties
Brinell Hardness | 190 | |
150 to 180 |
Elastic (Young's, Tensile) Modulus, GPa | 200 | |
190 |
Elongation at Break, % | 40 | |
21 |
Fatigue Strength, MPa | 200 | |
160 to 250 |
Poisson's Ratio | 0.28 | |
0.29 |
Shear Modulus, GPa | 77 | |
74 |
Shear Strength, MPa | 400 | |
310 to 370 |
Tensile Strength: Ultimate (UTS), MPa | 580 | |
500 to 590 |
Tensile Strength: Yield (Proof), MPa | 230 | |
230 to 350 |
Thermal Properties
Latent Heat of Fusion, J/g | 290 | |
260 |
Maximum Temperature: Mechanical, °C | 940 | |
480 |
Melting Completion (Liquidus), °C | 1430 | |
1470 |
Melting Onset (Solidus), °C | 1380 | |
1430 |
Specific Heat Capacity, J/kg-K | 480 | |
470 |
Thermal Conductivity, W/m-K | 15 | |
41 |
Thermal Expansion, µm/m-K | 17 | |
13 |
Electrical Properties
Electrical Conductivity: Equal Volume, % IACS | 2.4 | |
7.6 |
Electrical Conductivity: Equal Weight (Specific), % IACS | 2.7 | |
8.8 |
Otherwise Unclassified Properties
Base Metal Price, % relative | 16 | |
4.1 |
Density, g/cm3 | 7.8 | |
7.9 |
Embodied Carbon, kg CO2/kg material | 3.2 | |
1.8 |
Embodied Energy, MJ/kg | 46 | |
23 |
Embodied Water, L/kg | 140 | |
62 |
Common Calculations
PREN (Pitting Resistance) | 18 | |
6.4 |
Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 190 | |
84 to 110 |
Resilience: Unit (Modulus of Resilience), kJ/m3 | 140 | |
140 to 320 |
Stiffness to Weight: Axial, points | 14 | |
13 |
Stiffness to Weight: Bending, points | 25 | |
24 |
Strength to Weight: Axial, points | 21 | |
18 to 21 |
Strength to Weight: Bending, points | 20 | |
18 to 20 |
Thermal Diffusivity, mm2/s | 4.0 | |
11 |
Thermal Shock Resistance, points | 12 | |
14 to 17 |
Alloy Composition
Carbon (C), % | 0.040 to 0.1 | |
0.050 to 0.15 |
Chromium (Cr), % | 17 to 19 | |
2.8 to 3.3 |
Iron (Fe), % | 65.4 to 74 | |
94.4 to 96 |
Manganese (Mn), % | 0 to 2.0 | |
0.3 to 0.6 |
Molybdenum (Mo), % | 0 | |
0.9 to 1.1 |
Nickel (Ni), % | 9.0 to 12 | |
0 |
Phosphorus (P), % | 0 to 0.045 | |
0 to 0.025 |
Silicon (Si), % | 0 to 0.75 | |
0 to 0.5 |
Sulfur (S), % | 0 to 0.030 | |
0 to 0.025 |
Titanium (Ti), % | 0 to 0.7 | |
0 |