UNS S44660 (26-3-3) Stainless Steel
S44660 stainless steel is a ferritic stainless steel formulated for primary forming into wrought products. Cited properties are appropriate for the annealed condition. S44660 is the UNS number for this material. 26-3-3 is the common industry name.
It has a fairly high base cost among wrought ferritic stainless steels. In addition, it has a fairly high embodied energy and a fairly high tensile strength.
The graph bars on the material properties cards below compare S44660 stainless steel to: wrought ferritic 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
210
Elastic (Young's, Tensile) Modulus
210 GPa 30 x 106 psi
Elongation at Break
20 %
Fatigue Strength
330 MPa 48 x 103 psi
Poisson's Ratio
0.27
Rockwell B Hardness
88
Shear Modulus
81 GPa 12 x 106 psi
Shear Strength
410 MPa 59 x 103 psi
Tensile Strength: Ultimate (UTS)
660 MPa 95 x 103 psi
Tensile Strength: Yield (Proof)
510 MPa 74 x 103 psi
Thermal Properties
Latent Heat of Fusion
300 J/g
Maximum Temperature: Corrosion
640 °C 1190 °F
Maximum Temperature: Mechanical
1100 °C 2010 °F
Melting Completion (Liquidus)
1460 °C 2660 °F
Melting Onset (Solidus)
1410 °C 2580 °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
11 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
2.5 % IACS
Electrical Conductivity: Equal Weight (Specific)
2.9 % IACS
Otherwise Unclassified Properties
Base Metal Price
21 % relative
Density
7.7 g/cm3 480 lb/ft3
Embodied Carbon
4.3 kg CO2/kg material
Embodied Energy
61 MJ/kg 26 x 103 BTU/lb
Embodied Water
180 L/kg 21 gal/lb
Common Calculations
PREN (Pitting Resistance)
38
Resilience: Ultimate (Unit Rupture Work)
120 MJ/m3
Resilience: Unit (Modulus of Resilience)
640 kJ/m3
Stiffness to Weight: Axial
15 points
Stiffness to Weight: Bending
25 points
Strength to Weight: Axial
24 points
Strength to Weight: Bending
22 points
Thermal Diffusivity
4.5 mm2/s
Thermal Shock Resistance
21 points
Alloy Composition
Among wrought stainless steels, the composition of S44660 stainless steel is notable for containing a comparatively high amount of chromium (Cr) and including titanium (Ti). Chromium is the defining alloying element of stainless steel. Higher chromium content imparts additional corrosion resistance. Titanium is used to broadly improve mechanical properties.
| Fe | 60.4 to 71 | |
| Cr | 25 to 28 | |
| Mo | 3.0 to 4.0 | |
| Ni | 1.0 to 3.5 | |
| Nb | 0.2 to 1.0 | |
| Ti | 0.2 to 1.0 | |
| Mn | 0 to 1.0 | |
| Si | 0 to 1.0 | |
| P | 0 to 0.040 | |
| N | 0 to 0.040 | |
| C | 0 to 0.030 | |
| S | 0 to 0.030 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
Machining of Stainless Steels and Super Alloys: Traditional and Nontraditional Techniques, Helmi A. Youssef, 2016
ASTM A240: Standard Specification for Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip for Pressure Vessels and for General Applications
Welding Metallurgy of Stainless Steels, Erich Folkhard et al., 2012
ASTM A959: Standard Guide for Specifying Harmonized Standard Grade Compositions for Wrought Stainless Steels
Properties and Selection: Irons, Steels and High Performance Alloys, ASM Handbook vol. 1, ASM International, 1993
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