AISI 4340 Alloy Steel
UNS G41400AISI 4340 Alloy Steel
AISI 4340 alloy steel is a medium carbon, low alloy steel known for its toughness and strength in relatively large sections. AISI 4340 alloy steel is also one kind of nickel chromium molybdenum steels. AISI 4340 alloy steel is generally supplied hardened and tempered in the tensile range of 930 – 1080 Mpa. Pre-hardened and tempered AISI 4340 alloy steel can be further surface hardened by flame or induction hardening and by nitriding. AISI 4340 alloy steel has good shock and impact resistance as well as wear and abrasion resistance in the hardened condition. AISI 4340 alloy steel properties offer good ductility in the annealed condition, allowing it to be bent or formed.
AISI 4340 alloy steel is mainly used in power transmission gears and shafts, aircraft landing gear, and other structural parts.
Product forms include bar, seamless tubing, and plate.
Standards
- UNS G43400
Characteristics
- good ductility and formability in the annealed condition
- high strength and toughness in relatively large sections
- higher tensile/yield strength than 4140 can provide
Physical Properties
- Density: 0.284 LB/in³ (7.85 g/cm³)
- Melting Point: 2600°F (1427°C)
- Modulus of Elasticity: 29.7 x10⁶psi (205 Gpa)
- Magnetic Permeability:
Chemical Composition
C
Mn
S
P
Si
Cr
Mo
Fe
Mechanical Properties
KSI (MPa)
KSI (MPa)
HRB (BHN)
Specialty Steel Supply makes all reasonable efforts to ensure the accuracy and correctness of the data found on this website and the associated documents but makes no representations or warranties as to the data’s accuracy, correctness or reliability. All data are for general information only and not for providing design advice. It is the responsibility of the user to test specific alloys under actual service conditions to determine their suitability for a particular purpose.
Stainless and Alloys
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Specialty Steel Supply Inc. is one of the largest distributors of austenitic, precipitation hardened, duplex and martensitic stainless steels. We have a wide range of products and types of stainless steel round bar and our well trained staff offers many years of experience in all aspects of the steel industry. Our ability to procure and source metals from all parts of the world allows us to stay competitive in a global marketplace. We are committed to developing and servicing just in time inventory programs.
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19201 Circle Lake Drive
Pinehurst, Texas 77362
info@specialtysteelsupply.com
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