AISI 4340 Steel (Q&T)

Verifiedmetal
UNS G43400· AISI 4340· 4340· EN24

AISI 4340 is an ultra-high-strength low-alloy steel with excellent hardenability. Widely used for aircraft landing gear, shafts, and gears where very high strength-to-weight ratio is needed.

landing geardrivetrain shaftshigh-strength fastenersgearspressure vessels

Compliance & Regulations

?Conflict Free?RoHS?REACH?TSCA?Prop 65

Tempers & Conditions

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PropertyValueUnitConditionsSource
Charpy Impact vs Temperature(CVN(T))
Curve (9 pts)
J
Compressive Tangent Modulus vs Stress(Etn(σ))
Curve (10 pts)
Pa21°C · L
Fracture Toughness(KIC)
Pa·√m
Poisson's Ratio(ν)
-
S–N Curve (Wöhler)(S–N)
Pa38 entriesClick to expand
Stress–Strain Curve(σ–ε)
Curve (10 pts)
Pa20°C
Stress–Strain Curve (buckling region, ≤ 2% strain)(σ–ε (low-strain))
Pa7 entriesClick to expand
Yield Strength (0.2% offset)(σy)2 entries
PaQ&T 315°C
Curve (14 pts)
PaL
Young's Modulus(E)2 entries
Pa
Curve (10 pts)
PaL
N entriesMultiple entries per property — large groups are collapsed; click a summary row to expand. Use filters above to narrow by form / heat treatment / basis.
Verified Unverified Low confidence (<80%) Link to source
PropertyValueUnitConditionsSource
CTE vs Temperature(α(T))
Curve (17 pts)
1/K
Specific Heat Capacity(Cp)
J/(kg·K)
Thermal Conductivity(k)
W/(m·K)
Thermal Conductivity vs Temperature(k(T))
Curve (14 pts)
W/(m·K)
Verified Unverified Low confidence (<80%) Link to source
PropertyValueUnitConditionsSource
Density(ρ)
kg/m³
Verified Unverified Low confidence (<80%) Link to source

Regulatory Screening

Environmental

Quality & Standards

Industry-Specific

RoHS, REACH, and Prop 65 statuses are validated against official substance lists (ECHA SVHC Candidate List, OEHHA Prop 65, RoHS Annex II). Other regulations are estimated from composition and material classification. All screening is a starting point for due diligence — always verify with your supplier before making compliance decisions.