AISI 4340 Steel (Q&T)
VerifiedmetalUNS 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
Property OverviewNormalized to typical max values
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| Property | Value | Unit | Conditions | Source | |
|---|---|---|---|---|---|
Charpy Impact vs Temperature(CVN(T)) | Curve (9 pts) | J | — | ||
Compressive Tangent Modulus vs Stress(Etn(σ)) | Curve (10 pts) | Pa | 21°C · L | ||
Fracture Toughness(KIC) | 50,000,000 | Pa·√m | — | — | |
Poisson's Ratio(ν) | 0.2900 | - | — | — | |
S–N Curve (Wöhler)(S–N) | — | Pa | 38 entriesClick to expand | ||
Stress–Strain Curve(σ–ε) | Curve (10 pts) | Pa | 20°C | ||
Stress–Strain Curve (buckling region, ≤ 2% strain)(σ–ε (low-strain)) | — | Pa | 7 entriesClick to expand | ||
Yield Strength (0.2% offset)(σy)2 entries | 1.470 | GPa | Q&T 315°C | — | |
| ↳ | Curve (14 pts) | Pa | L | ||
Young's Modulus(E)2 entries | 200.0 | GPa | — | — | |
| ↳ | Curve (10 pts) | Pa | L | ||
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
| Property | Value | Unit | Conditions | Source | |
|---|---|---|---|---|---|
CTE vs Temperature(α(T)) | Curve (17 pts) | 1/K | — | ||
Specific Heat Capacity(Cp) | 475 | J/(kg·K) | — | — | |
Thermal Conductivity(k) | 44.50 | W/(m·K) | — | — | |
Thermal Conductivity vs Temperature(k(T)) | Curve (14 pts) | W/(m·K) | — |
Verified Unverified Low confidence (<80%) Link to source
| Property | Value | Unit | Conditions | Source | |
|---|---|---|---|---|---|
Density(ρ) | 7.850 | 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.