UNS S15500 (15-5 PH, 1.4545, XM-12) Stainless Steel
S15500 stainless steel is a precipitation-hardening stainless steel formulated for primary forming into wrought products. XM-12 is the ASTM designation for this material. 1.4545 is the EN numeric designation. S15500 is the UNS number. And 15-5 PH is the common industry name.
It has a moderately low embodied energy among the wrought precipitation-hardening stainless steels in the database.
The properties of S15500 stainless steel include seven common variations. This page shows summary ranges across all of them. For more specific values, follow the links immediately below. The graph bars on the material properties cards further below compare S15500 stainless steel to: wrought precipitation-hardening 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
290 to 430
Elastic (Young's, Tensile) Modulus
190 GPa 28 x 106 psi
Elongation at Break
6.8 to 16 %
Fatigue Strength
350 to 650 MPa 51 to 95 x 103 psi
Impact Strength: V-Notched Charpy
7.8 to 53 J 5.7 to 39 ft-lb
Poisson's Ratio
0.28
Reduction in Area
17 to 40 %
Rockwell C Hardness
27 to 46
Shear Modulus
75 GPa 11 x 106 psi
Shear Strength
540 to 870 MPa 79 to 130 x 103 psi
Tensile Strength: Ultimate (UTS)
890 to 1490 MPa 130 to 220 x 103 psi
Tensile Strength: Yield (Proof)
590 to 1310 MPa 85 to 190 x 103 psi
Thermal Properties
Latent Heat of Fusion
280 J/g
Maximum Temperature: Corrosion
440 °C 830 °F
Maximum Temperature: Mechanical
820 °C 1510 °F
Melting Completion (Liquidus)
1430 °C 2600 °F
Melting Onset (Solidus)
1380 °C 2520 °F
Specific Heat Capacity
480 J/kg-K 0.11 BTU/lb-°F
Thermal Conductivity
17 W/m-K 9.8 BTU/h-ft-°F
Thermal Expansion
11 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
2.2 % IACS
Electrical Conductivity: Equal Weight (Specific)
2.5 % IACS
Otherwise Unclassified Properties
Base Metal Price
13 % relative
Density
7.8 g/cm3 490 lb/ft3
Embodied Carbon
2.7 kg CO2/kg material
Embodied Energy
39 MJ/kg 17 x 103 BTU/lb
Embodied Water
130 L/kg 15 gal/lb
Common Calculations
PREN (Pitting Resistance)
15
Resilience: Ultimate (Unit Rupture Work)
98 to 120 MJ/m3
Resilience: Unit (Modulus of Resilience)
890 to 4460 kJ/m3
Stiffness to Weight: Axial
14 points
Stiffness to Weight: Bending
25 points
Strength to Weight: Axial
32 to 53 points
Strength to Weight: Bending
26 to 37 points
Thermal Diffusivity
4.6 mm2/s
Thermal Shock Resistance
30 to 50 points
Alloy Composition
Among wrought stainless steels, the composition of S15500 stainless steel is notable for including niobium (Nb) and copper (Cu). Niobium is primarily used to improve yield strength, particularly at elevated temperatures. Copper is used to improve resistance to acids, and to improve formability.
| Fe | 71.9 to 79.9 | |
| Cr | 14 to 15.5 | |
| Ni | 3.5 to 5.5 | |
| Cu | 2.5 to 4.5 | |
| Mn | 0 to 1.0 | |
| Si | 0 to 1.0 | |
| Nb | 0.15 to 0.45 | |
| C | 0 to 0.070 | |
| P | 0 to 0.040 | |
| S | 0 to 0.030 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
ASTM A564: Standard Specification for Hot-Rolled and Cold-Finished Age-Hardening Stainless Steel Bars and Shapes
Metallic Materials: Physical, Mechanical, and Corrosion Properties, Philip A. Schweitzer, 2003
Welding Metallurgy and Weldability of Stainless Steels, John C. Lippold and Damian J. Kotecki, 2005
ASTM A959: Standard Guide for Specifying Harmonized Standard Grade Compositions for Wrought Stainless Steels
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