ASTM A242 HSLA Steel
ASTM A242 HSLA steel is an alloy steel formulated for primary forming into wrought products. Cited properties are appropriate for the as-fabricated (no temper or treatment) condition. ASTM A242 is the defining standard for this material. Additionally, the UNS number is K11510.
It has a very low base cost among wrought alloy steels in the same category. In addition, it has a very low electrical conductivity and a fairly high thermal conductivity.
The graph bars on the material properties cards below compare ASTM A242 HSLA steel to: wrought alloy steels in the same category (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
150
Elastic (Young's, Tensile) Modulus
190 GPa 27 x 106 psi
Elongation at Break
22 %
Fatigue Strength
230 MPa 34 x 103 psi
Poisson's Ratio
0.29
Shear Modulus
73 GPa 11 x 106 psi
Shear Strength
310 MPa 45 x 103 psi
Tensile Strength: Ultimate (UTS)
490 MPa 71 x 103 psi
Tensile Strength: Yield (Proof)
330 MPa 48 x 103 psi
Thermal Properties
Latent Heat of Fusion
250 J/g
Maximum Temperature: Mechanical
400 °C 750 °F
Melting Completion (Liquidus)
1460 °C 2670 °F
Melting Onset (Solidus)
1420 °C 2590 °F
Specific Heat Capacity
470 J/kg-K 0.11 BTU/lb-°F
Thermal Conductivity
52 W/m-K 30 BTU/h-ft-°F
Thermal Expansion
13 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
7.1 % IACS
Electrical Conductivity: Equal Weight (Specific)
8.1 % IACS
Otherwise Unclassified Properties
Base Metal Price
1.9 % relative
Density
7.9 g/cm3 490 lb/ft3
Embodied Carbon
1.4 kg CO2/kg material
Embodied Energy
18 MJ/kg 7.8 x 103 BTU/lb
Embodied Water
46 L/kg 5.5 gal/lb
Common Calculations
Resilience: Ultimate (Unit Rupture Work)
95 MJ/m3
Resilience: Unit (Modulus of Resilience)
290 kJ/m3
Stiffness to Weight: Axial
13 points
Stiffness to Weight: Bending
24 points
Strength to Weight: Axial
17 points
Strength to Weight: Bending
17 points
Thermal Diffusivity
14 mm2/s
Thermal Shock Resistance
14 points
Alloy Composition
Among alloy steels, the composition of ASTM A242 HSLA steel is notable for including copper (Cu). Copper is used to improve corrosion resistance, and to add at least some degree of precipitation hardenability.
| Fe | 98.2 to 99.8 | |
| Mn | 0 to 1.0 | |
| Cu | 0.2 to 0.45 | |
| C | 0 to 0.15 | |
| P | 0 to 0.15 | |
| S | 0 to 0.050 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
ASTM A242: Standard Specification for High-Strength Low-Alloy Structural Steel
Properties and Selection: Irons, Steels and High Performance Alloys, ASM Handbook vol. 1, ASM International, 1993
Manufacture and Uses of Alloy Steels, Henry D. Hibbard, 2005
Ferrous Materials: Steel and Cast Iron, Hans Berns and Werner Theisen, 2008
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