UNS S34565 (Alloy 24, F49) Stainless Steel
S34565 stainless steel is a superaustenitic (highly alloyed) stainless steel formulated for primary forming into wrought products. Cited properties are appropriate for the annealed condition. S34565 is the UNS number for this material. Alloy 24 is the common industry name.
It has a very low base cost among wrought superaustenitic stainless steels. In addition, it has a very high tensile strength and a very low embodied energy.
The graph bars on the material properties cards below compare S34565 stainless steel to: wrought superaustenitic 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
200
Elastic (Young's, Tensile) Modulus
210 GPa 30 x 106 psi
Elongation at Break
39 %
Fatigue Strength
400 MPa 58 x 103 psi
Poisson's Ratio
0.28
Reduction in Area
45 %
Rockwell B Hardness
88
Shear Modulus
80 GPa 12 x 106 psi
Shear Strength
610 MPa 89 x 103 psi
Tensile Strength: Ultimate (UTS)
900 MPa 130 x 103 psi
Tensile Strength: Yield (Proof)
470 MPa 68 x 103 psi
Thermal Properties
Latent Heat of Fusion
310 J/g
Maximum Temperature: Corrosion
450 °C 840 °F
Maximum Temperature: Mechanical
1100 °C 2010 °F
Melting Completion (Liquidus)
1420 °C 2600 °F
Melting Onset (Solidus)
1380 °C 2510 °F
Specific Heat Capacity
470 J/kg-K 0.11 BTU/lb-°F
Thermal Conductivity
12 W/m-K 6.9 BTU/h-ft-°F
Thermal Expansion
15 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
1.9 % IACS
Electrical Conductivity: Equal Weight (Specific)
2.1 % IACS
Otherwise Unclassified Properties
Base Metal Price
28 % relative
Density
7.9 g/cm3 490 lb/ft3
Embodied Carbon
5.3 kg CO2/kg material
Embodied Energy
73 MJ/kg 31 x 103 BTU/lb
Embodied Water
210 L/kg 25 gal/lb
Common Calculations
PREN (Pitting Resistance)
47
Resilience: Ultimate (Unit Rupture Work)
300 MJ/m3
Resilience: Unit (Modulus of Resilience)
540 kJ/m3
Stiffness to Weight: Axial
14 points
Stiffness to Weight: Bending
25 points
Strength to Weight: Axial
32 points
Strength to Weight: Bending
26 points
Thermal Diffusivity
3.2 mm2/s
Thermal Shock Resistance
22 points
Alloy Composition
Among wrought stainless steels, the composition of S34565 stainless steel is notable for containing comparatively high amounts of manganese (Mn) and chromium (Cr). Manganese is used to improve ductility at elevated temperatures. It also permits a higher nitrogen content than would otherwise be possible. Chromium is the defining alloying element of stainless steel. Higher chromium content imparts additional corrosion resistance.
| Fe | 43.2 to 51.6 | |
| Cr | 23 to 25 | |
| Ni | 16 to 18 | |
| Mn | 5.0 to 7.0 | |
| Mo | 4.0 to 5.0 | |
| Si | 0 to 1.0 | |
| N | 0.4 to 0.6 | |
| Nb | 0 to 0.1 | |
| C | 0 to 0.030 | |
| P | 0 to 0.030 | |
| S | 0 to 0.010 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
ASTM A479: Standard Specification for Stainless Steel Bars and Shapes for Use in Boilers and Other Pressure Vessels
ASTM A182: Standard Specification for Forged or Rolled Alloy and Stainless Steel Pipe Flanges, Forged Fittings, and Valves and Parts for High-Temperature Service
ASTM A240: Standard Specification for Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip for Pressure Vessels and for General Applications
ASTM A959: Standard Guide for Specifying Harmonized Standard Grade Compositions for Wrought Stainless Steels
Corrosion of Austenitic Stainless Steels: Mechanism, Mitigation and Monitoring, H. S. Khatak and B. Raj (editors), 2002
Pressure Vessels: External Pressure Technology, 2nd ed., Carl T. F. Ross, 2011
Austenitic Stainless Steels: Microstructure and Mechanical Properties, P. Marshall, 1984
ASM Specialty Handbook: Stainless Steels, J. R. Davis (editor), 1994
Advances in Stainless Steels, Baldev Raj et al. (editors), 2010