ACI-ASTM CD4MCu (ASTM A890 Grade 1A, J93370) Cast Stainless Steel
ACI-ASTM CD4MCu steel is a duplex stainless steel formulated for casting. Cited properties are appropriate for the normalized and tempered condition. CD4MCu is the designation in both the ACI and ASTM systems for this material. ASTM A890 Grade 1A is the ASTM designation. And J93370 is the UNS number.
It has a moderately low ductility and a moderately high tensile strength among cast duplex stainless steels.
The graph bars on the material properties cards below compare ACI-ASTM CD4MCu steel to: cast duplex stainless 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
Elastic (Young's, Tensile) Modulus
200 GPa 29 x 106 psi
Elongation at Break
18 %
Fatigue Strength
340 MPa 50 x 103 psi
Poisson's Ratio
0.27
Shear Modulus
79 GPa 11 x 106 psi
Tensile Strength: Ultimate (UTS)
770 MPa 110 x 103 psi
Tensile Strength: Yield (Proof)
550 MPa 80 x 103 psi
Thermal Properties
Latent Heat of Fusion
300 J/g
Maximum Temperature: Corrosion
450 °C 840 °F
Maximum Temperature: Mechanical
1100 °C 2010 °F
Melting Completion (Liquidus)
1430 °C 2600 °F
Melting Onset (Solidus)
1380 °C 2520 °F
Specific Heat Capacity
480 J/kg-K 0.11 BTU/lb-°F
Thermal Conductivity
17 W/m-K 9.6 BTU/h-ft-°F
Thermal Expansion
13 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
2.2 % IACS
Electrical Conductivity: Equal Weight (Specific)
2.5 % IACS
Otherwise Unclassified Properties
Base Metal Price
18 % relative
Density
7.8 g/cm3 490 lb/ft3
Embodied Carbon
3.5 kg CO2/kg material
Embodied Energy
49 MJ/kg 21 x 103 BTU/lb
Embodied Water
180 L/kg 21 gal/lb
Common Calculations
PREN (Pitting Resistance)
32
Resilience: Ultimate (Unit Rupture Work)
130 MJ/m3
Resilience: Unit (Modulus of Resilience)
760 kJ/m3
Stiffness to Weight: Axial
14 points
Stiffness to Weight: Bending
25 points
Strength to Weight: Axial
28 points
Strength to Weight: Bending
24 points
Thermal Diffusivity
4.5 mm2/s
Thermal Shock Resistance
21 points
Alloy Composition
Among cast stainless steels, the composition of ACI-ASTM CD4MCu steel is notable for containing a comparatively high amount of chromium (Cr) and including copper (Cu). Chromium is the defining alloying element of stainless steel. Higher chromium content imparts additional corrosion resistance. Copper is primarily used to improve resistance to acids.
| Fe | 59.9 to 66.3 | |
| Cr | 24.5 to 26.5 | |
| Ni | 4.8 to 6.0 | |
| Cu | 2.8 to 3.3 | |
| Mo | 1.8 to 2.3 | |
| Mn | 0 to 1.0 | |
| Si | 0 to 1.0 | |
| C | 0 to 0.040 | |
| P | 0 to 0.040 | |
| S | 0 to 0.040 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
ASTM A890: Standard Specification for Castings, Iron-Chromium-Nickel-Molybdenum Corrosion-Resistant, Duplex (Austenitic/Ferritic) for General Application
Duplex Stainless Steels, Iris Alvarez-Armas and Suzanne Degallaix-Moreuil (editors), 2009
Duplex Stainless Steels: Microstructure, Properties and Applications, Robert N. Gunn (editor), 1997
Corrosion of Stainless Steels, A. John Sedriks, 1996
ASM Specialty Handbook: Stainless Steels, J. R. Davis (editor), 1994
Advances in Stainless Steels, Baldev Raj et al. (editors), 2010