Grade FDSiCr Spring Steel
Grade FDSiCr steel is an alloy steel formulated for primary forming into wrought products. Cited properties are appropriate for the hardened (H) condition. It has a very low density among EN wrought alloy steels. In addition, it has a very low melting temperature and a very high tensile strength.
The graph bars on the material properties cards below compare grade FDSiCr steel to: EN wrought 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
580
Elastic (Young's, Tensile) Modulus
190 GPa 27 x 106 psi
Poisson's Ratio
0.29
Reduction in Area
42 %
Shear Modulus
80 GPa 12 x 106 psi
Tensile Strength: Ultimate (UTS)
1930 MPa 280 x 103 psi
Thermal Properties
Latent Heat of Fusion
270 J/g
Maximum Temperature: Mechanical
410 °C 780 °F
Melting Completion (Liquidus)
1440 °C 2620 °F
Melting Onset (Solidus)
1400 °C 2550 °F
Specific Heat Capacity
480 J/kg-K 0.11 BTU/lb-°F
Thermal Conductivity
48 W/m-K 28 BTU/h-ft-°F
Thermal Expansion
13 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
7.3 % IACS
Electrical Conductivity: Equal Weight (Specific)
8.5 % IACS
Otherwise Unclassified Properties
Base Metal Price
2.2 % relative
Density
7.7 g/cm3 480 lb/ft3
Embodied Carbon
1.5 kg CO2/kg material
Embodied Energy
20 MJ/kg 8.4 x 103 BTU/lb
Embodied Water
48 L/kg 5.8 gal/lb
Common Calculations
Stiffness to Weight: Axial
13 points
Stiffness to Weight: Bending
25 points
Strength to Weight: Axial
69 points
Strength to Weight: Bending
44 points
Thermal Diffusivity
13 mm2/s
Thermal Shock Resistance
58 points
Alloy Composition
Among alloy steels, the composition of grade FDSiCr steel is notable for containing a comparatively high amount of silicon (Si). Silicon content is typically governed by metallurgical processing concerns, and not its effects on final material properties. However, it does have a modest strengthening effect.
| Fe | 96.5 to 97.8 | |
| Si | 1.2 to 1.6 | |
| Mn | 0.5 to 0.9 | |
| Cr | 0.5 to 0.8 | |
| C | 0.5 to 0.6 | |
| Cu | 0 to 0.12 | |
| P | 0 to 0.030 | |
| S | 0 to 0.025 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
EN 10270-2: Steel wire for mechanical spring - Part 2: Oil hardened and tempered spring steel wire
ASM Specialty Handbook: Carbon and Alloy Steels, J. R. Davis (editor), 1996
Manufacture and Uses of Alloy Steels, Henry D. Hibbard, 2005
CRC Materials Science and Engineering Handbook, 4th ed., James F. Shackelford et al. (editors), 2015
Steels: Processing, Structure, and Performance, 2nd ed., George Krauss, 2015