AISI 4340 Steel, normalized, 100 mm (4 in.) round

Subcategory: AISI 4000 Series Steel; Ferrous Metal; Low Alloy Steel; Medium Carbon Steel; Metal

Key Words: alloy steels, UNS G43400, AMS 5331, AMS 6359, AMS 6414, AMS 6415, ASTM A322, ASTM A331, ASTM A505, ASTM A519, ASTM A547, ASTM A646, MIL SPEC MIL-S-16974, B.S. 817 M 40 (UK), SAE J404, SAE J412, SAE J770, DIN 1.6565, JIS SNCM 8, IS 1570 40Ni2Cr1Mo28, IS 1570 40NiCr1Mo15

Component   Wt. %
C0.37 - 0.43 
Cr0.7 - 0.9 
Component   Wt. %
Mo0.2 - 0.3 
Component   Wt. %
PMax 0.035 
SMax 0.04 

Physical PropertiesMetricEnglishComments
Density7.85 g/cc0.284 lb/in 

Mechanical Properties
Hardness, Brinell321321 
Hardness, Knoop348348 Converted from Brinell hardness.
Hardness, Rockwell B9999 Converted from Brinell hardness.
Hardness, Rockwell C3535 Converted from Brinell hardness.
Hardness, Vickers339339 Converted from Brinell hardness.
Tensile Strength, Ultimate1110 MPa161000 psi 
Tensile Strength, Yield710 MPa103000 psi 
Elongation at Break13.2 %13.2 % 
Reduction of Area36 %36 % 
Modulus of Elasticity205 GPa29700 ksi Typical for steel
Bulk Modulus140 GPa20300 ksi Typical for steel.
Poisson's Ratio0.290.29 Calculated
Machinability50 %50 % annealed and cold drawn. Based on 100% machinability for AISI 1212 steel.
Shear Modulus80 GPa11600 ksi Typical for steel.

Electrical Properties
Electrical Resistivity2.48e-005 ohm-cm2.48e-005 ohm-cm 20C (68F)
Electrical Resistivity at Elevated Temperature2.98e-005 ohm-cm2.98e-005 ohm-cm 100C (212F)
Electrical Resistivity at Elevated Temperature5.52e-005 ohm-cm5.52e-005 ohm-cm 400C (750F)
Electrical Resistivity at Elevated Temperature7.97e-005 ohm-cm7.97e-005 ohm-cm 600C (1110F)

Thermal Properties
CTE, linear 20C12.3 m/m-C6.83 in/in-F specimen oil hardened, 600C (1110F) temper; 20-100C (68-212F)
CTE, linear 20C12.7 m/m-C7.06 in/in-F specimen oil hardened, 600C (1110F) temper; 20-200C (68-390F)
CTE, linear 250C12.6 m/m-C7 in/in-F 1.88% Ni, normalized, tempered; 21-260C (70-500F)
CTE, linear 250C13.7 m/m-C7.61 in/in-F specimen oil hardened, 600C (1110F) temper; 20-400C (68-750F)
CTE, linear 500C13.7 m/m-C7.61 in/in-F 1.88% Ni, normalized and tempered; 21-540C (70-1000F)
CTE, linear 500C13.9 m/m-C7.72 in/in-F 1.90% Ni, quenched, tempered; 21-540C (70-1000F)
CTE, linear 500C14.5 m/m-C8.06 in/in-F specimen oil hardened, 600C (1110F) temper; 20-600C (68-1110F)
Specific Heat Capacity0.475 J/g-C0.114 BTU/lb-F Typical 4000 series steel
Thermal Conductivity44.5 W/m-K309 BTU-in/hr-ft-F Typical steel

References for this datasheet.

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