ACI-ASTM CF3MN (J92804) Cast Stainless Steel
ACI-ASTM CF3MN steel is an austenitic stainless steel formulated for casting. Cited properties are appropriate for the heat treated (HT) condition. CF3MN is the designation in both the ACI and ASTM systems for this material. J92804 is the UNS number.
It has a moderately high tensile strength and a moderately high ductility among cast austenitic stainless steels.
The graph bars on the material properties cards below compare ACI-ASTM CF3MN steel to: cast austenitic 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
Brinell Hardness
170
Elastic (Young's, Tensile) Modulus
200 GPa 29 x 106 psi
Elongation at Break
39 %
Fatigue Strength
250 MPa 36 x 103 psi
Poisson's Ratio
0.28
Shear Modulus
78 GPa 11 x 106 psi
Tensile Strength: Ultimate (UTS)
580 MPa 84 x 103 psi
Tensile Strength: Yield (Proof)
290 MPa 42 x 103 psi
Thermal Properties
Latent Heat of Fusion
300 J/g
Maximum Temperature: Corrosion
420 °C 790 °F
Maximum Temperature: Mechanical
1010 °C 1840 °F
Melting Completion (Liquidus)
1440 °C 2620 °F
Melting Onset (Solidus)
1390 °C 2540 °F
Specific Heat Capacity
480 J/kg-K 0.11 BTU/lb-°F
Thermal Conductivity
15 W/m-K 8.9 BTU/h-ft-°F
Thermal Expansion
16 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
2.1 % IACS
Electrical Conductivity: Equal Weight (Specific)
2.4 % IACS
Otherwise Unclassified Properties
Base Metal Price
19 % relative
Density
7.8 g/cm3 490 lb/ft3
Embodied Carbon
3.9 kg CO2/kg material
Embodied Energy
53 MJ/kg 23 x 103 BTU/lb
Embodied Water
160 L/kg 19 gal/lb
Common Calculations
PREN (Pitting Resistance)
30
Resilience: Ultimate (Unit Rupture Work)
190 MJ/m3
Resilience: Unit (Modulus of Resilience)
210 kJ/m3
Stiffness to Weight: Axial
14 points
Stiffness to Weight: Bending
25 points
Strength to Weight: Axial
20 points
Strength to Weight: Bending
20 points
Thermal Diffusivity
4.1 mm2/s
Thermal Shock Resistance
13 points
Alloy Composition
Among cast stainless steels, the composition of ACI-ASTM CF3MN steel is notable for including nitrogen (N) and containing a comparatively high amount of molybdenum (Mo). Nitrogen has a substantial strengthening effect, but has a complex (frequently negative) relationship with corrosion resistance. Molybdenum is used to facilitate tempering. In addition, it offers modest bonuses to a wide range of material properties.
| Fe | 58.7 to 71.9 | |
| Cr | 17 to 22 | |
| Ni | 9.0 to 13 | |
| Mo | 2.0 to 3.0 | |
| Mn | 0 to 1.5 | |
| Si | 0 to 1.5 | |
| N | 0.1 to 0.2 | |
| P | 0 to 0.040 | |
| S | 0 to 0.040 | |
| C | 0 to 0.030 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
ASTM A743: Standard Specification for Castings, Iron-Chromium, Iron-Chromium-Nickel, Corrosion Resistant, for General Application
Metallic Materials: Physical, Mechanical, and Corrosion Properties, Philip A. Schweitzer, 2003
Corrosion of Austenitic Stainless Steels: Mechanism, Mitigation and Monitoring, H. S. Khatak and B. Raj (editors), 2002
Austenitic Stainless Steels: Microstructure and Mechanical Properties, P. Marshall, 1984
Properties and Selection: Irons, Steels and High Performance Alloys, ASM Handbook vol. 1, ASM International, 1993
ASM Specialty Handbook: Stainless Steels, J. R. Davis (editor), 1994
Advances in Stainless Steels, Baldev Raj et al. (editors), 2010