4340 is nickel-chromium-molybdenum alloy steel. It is ideal for highly stressed parts, and it can attain much deeper hardenability than 4100 series steel. 4340 also has excellent non-distorting properties for an alloy steel, with high fatigue/tensile ratio and the capability to maintain strength, ductility, and toughness at relatively high temperatures. Meets MIL-S-5000, AMS-6415, and others.

AED stocks several sizes of 4340 round bar, generally in the cold finished and normalized condition. Other sizes and conditions, as well as hex, flat and square bar may also be available upon request.

Typical Mechanical Properties (Minimum)

Property	Annealed
Tensile Strength (psi)	110,000
Yield Point (psi)	66,000
Elongation % in 2	23
Reduction of Area (%)	49
Brinell Hardness	197

Note: The Typical Mechanical Properties listed have been compiled from a variety of sources. Information is deemed reliable, but not guaranteed. Data is provided for information only, NOT FOR DESIGN PURPOSES.

Product Availability

Diameter	Weight / Foot (lbs)	SKU	Add to Quote
0.3750	0.3759	1 43B37	+
0.5000	0.6682	1 43B50	+
0.6250	1.044	1 43B62	+
0.7500	1.504	1 43B75	+
1.0000	2.673	1 43B0100	+
1.2500	4.176	1 43B0125	+
1.5000	6.014	1 43B0150	+

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