SAE-AISI A9 (T30109) Air-Hardening Steel
Tool Steels
Property Overview
Density7.8g/cm³
Elastic Modulus190GPa
Tensile Strength770 to 2030MPa
Yield StrengthUnknown
Brinell HardnessUnknown
Maximum Service TemperatureUnknown
Chemical Composition
C
0.45 to 0.55%
CR
4.8 to 5.5%
NI
1.3 to 1.8%
MO
1.3 to 1.8%
MN
0 to 0.5%
SI
1.0 to 1.2%
P
0 to 0.030%
S
0 to 0.030%
CU
0 to 0.25%
V
0.8 to 1.4%
FE
87 to 90.5%
Mechanical
Elastic (Young's, Tensile) Modulus
190 GPa
Poisson's Ratio
0.29
Shear Modulus
74 GPa
Tensile Strength: Ultimate (UTS)
770 to 2030 MPa
Physical
Density
7.8 g/cm 3
Thermal
Latent Heat of Fusion
280 J/g
Melting Completion (Liquidus)
1460 °C
Melting Onset (Solidus)
1410 °C
Specific Heat Capacity
470 J/kg-K
Thermal Conductivity
35 W/m-K
Thermal Diffusivity
9.6 mm 2 /s
Thermal Expansion
12 µm/m-K
Thermal Shock Resistance
25 to 66 points
Electrical
Electrical Conductivity: Equal Volume
7.9 % IACS
Electrical Conductivity: Equal Weight (Specific)
9.2 % IACS
Calculated
PREN (Pitting Resistance)
10
Stiffness to Weight: Axial
14 points
Stiffness to Weight: Bending
25 points
Strength to Weight: Axial
28 to 73 points
Strength to Weight: Bending
24 to 46 points
Environmental
Base Metal Price
7.0 % relative
Embodied Carbon
4.7 kg CO 2 /kg material
Embodied Energy
70 MJ/kg
Embodied Energy
70 MJ/kg 30 x 10 3 BTU/lb
Embodied Water
82 L/kg
Embodied Water
82 L/kg 9.7 gal/lb
Registered Designations & Aliases
SAE-AISI A9 (T30109) Air-Hardening SteelT30109
Standards
ASTM A681 ASTM A681: Standard Specification for Tool Steels Alloy
ASTM A681 ASTM A681: Standard Specification for Tool Steels Alloy Tool Steels, 5th ed., George Roberts et al., 1998 Tool Steels: Properties and Performance, Rafael A. Mesquita (editor), 2016