EN 1.4634 (X2CrAlSiNb18) Stainless Steel
EN 1.4634 stainless steel is a ferritic stainless steel formulated for primary forming into wrought products. Cited properties are appropriate for the annealed condition. 1.4634 is the EN numeric designation for this material. X2CrAlSiNb18 is the EN chemical designation.
It has a moderately high embodied energy among the wrought ferritic stainless steels in the database.
The graph bars on the material properties cards below compare EN 1.4634 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
Elastic (Young's, Tensile) Modulus
200 GPa 28 x 106 psi
Elongation at Break
21 %
Fatigue Strength
180 MPa 27 x 103 psi
Poisson's Ratio
0.28
Shear Modulus
77 GPa 11 x 106 psi
Shear Strength
340 MPa 49 x 103 psi
Tensile Strength: Ultimate (UTS)
540 MPa 78 x 103 psi
Tensile Strength: Yield (Proof)
280 MPa 41 x 103 psi
Thermal Properties
Latent Heat of Fusion
290 J/g
Maximum Temperature: Corrosion
500 °C 940 °F
Maximum Temperature: Mechanical
900 °C 1650 °F
Melting Completion (Liquidus)
1430 °C 2610 °F
Melting Onset (Solidus)
1390 °C 2530 °F
Specific Heat Capacity
480 J/kg-K 0.12 BTU/lb-°F
Thermal Conductivity
21 W/m-K 12 BTU/h-ft-°F
Thermal Expansion
10 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
2.5 % IACS
Electrical Conductivity: Equal Weight (Specific)
3.0 % IACS
Otherwise Unclassified Properties
Base Metal Price
13 % relative
Density
7.7 g/cm3 480 lb/ft3
Embodied Carbon
2.9 kg CO2/kg material
Embodied Energy
42 MJ/kg 18 x 103 BTU/lb
Embodied Water
140 L/kg 16 gal/lb
Common Calculations
PREN (Pitting Resistance)
19
Resilience: Ultimate (Unit Rupture Work)
93 MJ/m3
Resilience: Unit (Modulus of Resilience)
200 kJ/m3
Stiffness to Weight: Axial
14 points
Stiffness to Weight: Bending
25 points
Strength to Weight: Axial
20 points
Strength to Weight: Bending
19 points
Thermal Diffusivity
5.8 mm2/s
Thermal Shock Resistance
19 points
Alloy Composition
Among wrought stainless steels, the composition of EN 1.4634 stainless steel is notable for including aluminum (Al) and niobium (Nb). Aluminum is used to improve oxidation resistance. It can also enhance the effects of heat treatment. Niobium is primarily used to improve yield strength, particularly at elevated temperatures.
| Fe | 74.9 to 81.8 | |
| Cr | 17.5 to 18.5 | |
| Si | 0.2 to 1.5 | |
| Al | 0.2 to 1.5 | |
| Nb | 0.3 to 1.0 | |
| Mn | 0 to 1.0 | |
| Ni | 0 to 0.5 | |
| Mo | 0 to 0.5 | |
| Cu | 0 to 0.5 | |
| P | 0 to 0.050 | |
| S | 0 to 0.050 | |
| C | 0 to 0.030 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
EN 10088-2: Stainless steels - Part 2: Technical delivery conditions for sheet/plate and strip of corrosion resisting steels for general purposes
Machining of Stainless Steels and Super Alloys: Traditional and Nontraditional Techniques, Helmi A. Youssef, 2016
EN 10088-1: Stainless steels - Part 1: List of stainless steels
Corrosion of Stainless Steels, A. John Sedriks, 1996
Advances in Stainless Steels, Baldev Raj et al. (editors), 2010