AISI 4340 Structural and constructional steels

Material group: Ferrous Alloys / Structural and constructional steels
Country / Standard: United States / AISI
Indicative price:

Data updates

Latest Update: 2024-07
Total number of updates: 16
Update History

This material has 1330 properties — only a subset is shown here.

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AISI 4340 Chemical Composition

CRITERIA
VALUE
UNIT
CAS NUMBER
CRITERIA
C
VALUE
0.38 – 0.43
UNIT
%
CAS NUMBER
7440-44-0
CRITERIA
Cr
VALUE
0.70 – 0.90
UNIT
%
CAS NUMBER
7440-47-3
CRITERIA
Cu
VALUE
≤ 0.35
UNIT
%
CAS NUMBER
7440-50-8
CRITERIA
Mn
VALUE
val1
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UNIT
%
CAS NUMBER
7439-96-5
CRITERIA
Mo
VALUE
val1
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UNIT
%
CAS NUMBER
7439-98-7
CRITERIA
Ni
VALUE
val1
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UNIT
%
CAS NUMBER
7440-02-0
CRITERIA
P
VALUE
val1
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UNIT
%
CAS NUMBER
7723-14-0
CRITERIA
Pb
VALUE
val1
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UNIT
%
CAS NUMBER
7439-92-1
CRITERIA
S
VALUE
val1
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UNIT
%
CAS NUMBER
7704-34-9
CRITERIA
Si
VALUE
val1
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UNIT
%
CAS NUMBER
7440-21-3

SAE J 404: 2009 / Chemical compositions of SAE alloy steels

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AISI 4340 Physical Properties

Temperature

PROPERTY / VALUE
Compression Modulus
200 GPa
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Modulus of Elasticity
190 — 210 GPa
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Thermal Conductivity
val1
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W/(m∙°C)
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Electrical Resistivity
val1
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Ω∙mm²/m
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Density
val1
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kg/dm³
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Electrical Conductivity
val1
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S/m
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Poisson Coefficient
val1
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Shear Modulus
val1
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GPa
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Coefficient of Thermal Expansion (CTE)
val1
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10-6/°C
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This material has 1330 properties — only a subset is shown here.

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AISI 4340 Heat Treatments

  • Normalizing: 871-927°C (1600-1700°F), air quenched. Annealing: 829-857°C (1525-1575°F). Furnace cool to 538°C (1000°F) or below (rate of furnace cool should be 28°C (50°F) per hour or slower). Recommended subcritical anneal temperature is 677°C (1250°F).
    Austenitizing: 816-843°C (1500-1550°F). Medium for quenching: oil.
  • Normalized by heating to 870-925°C in an atmosphere neutral to the specified carbon range, holding at heat for not less than 1 hour per 25 mm of maximum cross-section and cooling in air to room temperature and tempered by heating to not lower than 595°C, holding at heat for not less than1 hour and cooling in air. Harden by heating to 815°C +/-15°C holding at heat for not less than 30 minutes and quenching in oil. Double temper by heating to 425°C +/-8°C holding at heat for 2 hours +/-15 minutes and cooling in air after each tempering operation.

AISI 4340 Mechanical Properties

Temperature

PROPERTY / VALUE
Tensile Strength
≥ 677.5 MPa
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Brinell Hardness (HB)
187 — 322
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Elongation, A
val1
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%
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Compression Yield Strength
val1
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MPa
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Grain Size
val1
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Impact Energy
val1
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J
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Reduction of Area
val1
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%
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Rockwell Hardness (HR)
val1
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Yield Strength, Rp0.2
val1
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MPa
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AISI 4340 International Equivalent Materials

Showing 15 of 424 results.

MATERIAL
STANDARD
COUNTRY / PRODUCER
EQUIVALENCE CATEGORY
MATERIAL
SNB 24-1
STANDARD
JIS
COUNTRY / PRODUCER
Japan
EQUIVALENCE CATEGORY
Official
MATERIAL
SNCM439
STANDARD
JIS
COUNTRY / PRODUCER
Japan
EQUIVALENCE CATEGORY
Official
MATERIAL
G43400
STANDARD
UNS
COUNTRY / PRODUCER
United States
EQUIVALENCE CATEGORY
Official
MATERIAL
40Ni6Cr4Mo3
STANDARD
IS
COUNTRY / PRODUCER
India
EQUIVALENCE CATEGORY
Official
MATERIAL
40Ni2Cr1Mo28
STANDARD
IS
COUNTRY / PRODUCER
India
EQUIVALENCE CATEGORY
Official
MATERIAL
G43406
STANDARD
UNS
COUNTRY / PRODUCER
United States
EQUIVALENCE CATEGORY
Official
MATERIAL
J24060
STANDARD
UNS
COUNTRY / PRODUCER
United States
EQUIVALENCE CATEGORY
Official
MATERIAL
A 646 Grade 4340
STANDARD
ASTM
COUNTRY / PRODUCER
United States
EQUIVALENCE CATEGORY
Official
MATERIAL
EN 24
STANDARD
B.S.
COUNTRY / PRODUCER
United Kingdom
EQUIVALENCE CATEGORY
Official
MATERIAL
SNB 24-1
STANDARD
KS
COUNTRY / PRODUCER
Korea
EQUIVALENCE CATEGORY
Official
MATERIAL
SNB 24-2
STANDARD
KS
COUNTRY / PRODUCER
Korea
EQUIVALENCE CATEGORY
Official
MATERIAL
SNB 24-3
STANDARD
KS
COUNTRY / PRODUCER
Korea
EQUIVALENCE CATEGORY
Official
MATERIAL
SNB 24-4
STANDARD
KS
COUNTRY / PRODUCER
Korea
EQUIVALENCE CATEGORY
Official
MATERIAL
SNB 24-5
STANDARD
KS
COUNTRY / PRODUCER
Korea
EQUIVALENCE CATEGORY
Official
MATERIAL
4340
STANDARD
NBR
COUNTRY / PRODUCER
Brazil
EQUIVALENCE CATEGORY
Official

Equivalence categories reflect chemical-composition and mechanical-property comparison — always verify suitability against the governing specification for your application.

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  • 424Cross References
  • 75Composition
  • 214Mechanical Properties
  • 68Physical Properties
  • 24Heat Treatment
  • 18Metallography
  • 4Machinability
  • 5Stress-Strain
  • 2Formability
  • 32Fatigue
  • 3Fracture
  • -Creep
  • 1Joints
  • -Coatings
  • 114Dimensions
  • -Tribology
  • 2Corrosion
  • 1Ageing
  • -Weatherability
  • -Irradiation
  • 343Total Suppliers