ASTM A356 Grade 6 (J12073) Cast Steel
ASTM A356 grade 6 is an alloy steel formulated for casting. Cited properties are appropriate for the heat treated (HT) condition. ASTM A356 Grade 6 is the ASTM designation for this material. J12073 is the UNS number.
It has a fairly low tensile strength among cast alloy steels. In addition, it has a moderately high ductility and a moderately low embodied energy.
The graph bars on the material properties cards below compare ASTM A356 grade 6 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
170
Elastic (Young's, Tensile) Modulus
190 GPa 27 x 106 psi
Elongation at Break
25 %
Fatigue Strength
250 MPa 37 x 103 psi
Poisson's Ratio
0.29
Reduction in Area
39 %
Shear Modulus
73 GPa 11 x 106 psi
Tensile Strength: Ultimate (UTS)
550 MPa 80 x 103 psi
Tensile Strength: Yield (Proof)
350 MPa 50 x 103 psi
Thermal Properties
Latent Heat of Fusion
250 J/g
Maximum Temperature: Mechanical
430 °C 810 °F
Melting Completion (Liquidus)
1460 °C 2670 °F
Melting Onset (Solidus)
1420 °C 2590 °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
7.4 % IACS
Electrical Conductivity: Equal Weight (Specific)
8.4 % IACS
Otherwise Unclassified Properties
Base Metal Price
2.9 % relative
Density
7.8 g/cm3 490 lb/ft3
Embodied Carbon
1.6 kg CO2/kg material
Embodied Energy
21 MJ/kg 9.0 x 103 BTU/lb
Embodied Water
53 L/kg 6.3 gal/lb
Common Calculations
PREN (Pitting Resistance)
3.1
Resilience: Ultimate (Unit Rupture Work)
120 MJ/m3
Resilience: Unit (Modulus of Resilience)
320 kJ/m3
Stiffness to Weight: Axial
13 points
Stiffness to Weight: Bending
24 points
Strength to Weight: Axial
20 points
Strength to Weight: Bending
19 points
Thermal Diffusivity
11 mm2/s
Thermal Shock Resistance
16 points
Alloy Composition
Among cast alloy steels, the composition of ASTM A356 grade 6 is notable for containing a comparatively high amount of chromium (Cr). Chromium is used to improve corrosion resistance and most mechanical properties (particularly at higher temperatures).
| Fe | 96.2 to 98.1 | |
| Cr | 1.0 to 1.5 | |
| Mn | 0.5 to 0.8 | |
| Mo | 0.45 to 0.65 | |
| Si | 0 to 0.6 | |
| 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