ASTM A356 Grade 9 (J21610) Cast Steel
ASTM A356 grade 9 is an alloy steel formulated for casting. Cited properties are appropriate for the heat treated (HT) condition. ASTM A356 Grade 9 is the ASTM designation for this material. J21610 is the UNS number.
It has a very high embodied energy and a moderately low ductility among cast alloy steels.
The graph bars on the material properties cards below compare ASTM A356 grade 9 to: cast alloy steels (top), all iron alloys (middle), and the entire database (bottom). A full bar means this is the highest value in the relevant set. A half-full bar means it's 50% of the highest, and so on.
Mechanical Properties
Brinell Hardness
200
Elastic (Young's, Tensile) Modulus
190 GPa 27 x 106 psi
Elongation at Break
17 %
Fatigue Strength
310 MPa 45 x 103 psi
Poisson's Ratio
0.29
Reduction in Area
50 %
Shear Modulus
73 GPa 11 x 106 psi
Tensile Strength: Ultimate (UTS)
670 MPa 97 x 103 psi
Tensile Strength: Yield (Proof)
460 MPa 67 x 103 psi
Thermal Properties
Latent Heat of Fusion
260 J/g
Maximum Temperature: Mechanical
440 °C 820 °F
Melting Completion (Liquidus)
1470 °C 2680 °F
Melting Onset (Solidus)
1430 °C 2600 °F
Specific Heat Capacity
470 J/kg-K 0.11 BTU/lb-°F
Thermal Conductivity
41 W/m-K 24 BTU/h-ft-°F
Thermal Expansion
13 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
7.5 % IACS
Electrical Conductivity: Equal Weight (Specific)
8.6 % IACS
Otherwise Unclassified Properties
Base Metal Price
3.6 % relative
Density
7.8 g/cm3 490 lb/ft3
Embodied Carbon
2.4 kg CO2/kg material
Embodied Energy
33 MJ/kg 14 x 103 BTU/lb
Embodied Water
56 L/kg 6.7 gal/lb
Common Calculations
PREN (Pitting Resistance)
4.7
Resilience: Ultimate (Unit Rupture Work)
100 MJ/m3
Resilience: Unit (Modulus of Resilience)
570 kJ/m3
Stiffness to Weight: Axial
13 points
Stiffness to Weight: Bending
24 points
Strength to Weight: Axial
24 points
Strength to Weight: Bending
22 points
Thermal Diffusivity
11 mm2/s
Thermal Shock Resistance
19 points
Alloy Composition
Among cast alloy steels, the composition of ASTM A356 grade 9 is notable for containing a comparatively high amount of molybdenum (Mo) and including vanadium (V). Molybdenum is used to facilitate tempering. In addition, it offers modest bonuses to a wide range of material properties. Vanadium has a strong hardening effect, but this effect is particularly sensitive to the type of tempering.
| Fe | 95.2 to 97.2 | |
| Cr | 1.0 to 1.5 | |
| Mo | 0.9 to 1.2 | |
| Mn | 0.5 to 0.9 | |
| Si | 0.2 to 0.6 | |
| V | 0.2 to 0.35 | |
| C | 0 to 0.2 | |
| P | 0 to 0.035 | |
| S | 0 to 0.030 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
ASTM A356: Standard Specification for Steel Castings, Carbon, Low Alloy, and Stainless Steel, Heavy-Walled for Steam Turbines