SAE 8640 Alloy Steel
Mat Grades internal verification confirms source-backed fidelity and data integrity. It does not constitute external certification, ASTM/CDA endorsement, or guaranteed material conformity for procurement.
Key Engineering Properties
Representative source rows, qualified by their reported conditions. Inspect the tables below for all values, limits, and source notes.
Engineering Summary
SAE 8640 Alloy Steel. Source-scoped engineering data is shown with its reported limits and conditions. Unreported properties are not inferred.
Recognized Aliases
Source-backed commercial trade name and short designations cataloged in canonical data.
Standard Designations & Applicable Specifications
Semantically classified designations distinguishing primary standard identifiers, commercial trade names, and applicable specification references.
| System | Identifier | Standard System Name | Classification Notes & Provenance |
|---|---|---|---|
| SAEPRIMARY | 8640 | SAE | —Ref: Practical Data for Metallurgists, 19th edition |
| Standards Body | Specification Code | Specification Title / Scope | Relationship Type |
|---|---|---|---|
| SAE | SAE 8640 Alloy Steel Engineering Datasheet | Applicable specification reference. | Specification Reference |
Chemical Composition (Weight %)
Elemental limits and values from the cited source. Preserves exact semantic limits (minimums, maximums, and ranges).
| Element | Symbol | Atomic No. | Semantic Basis | Specified Value | Unit | Metallurgical Notes & Qualification | Data Status |
|---|---|---|---|---|---|---|---|
| Carbon | C | 6 | RANGE | 0.38 – 0.43 | wt% | Source cell: .38/.43. Scope: p7, SAE 8640.Ref: Metallus | VERIFIED |
| Manganese | Mn | 25 | RANGE | 0.75 – 1.00 | wt% | Source cell: .75/1.00. Scope: p7, SAE 8640.Ref: Metallus | VERIFIED |
| Chromium | Cr | 24 | RANGE | 0.40 – 0.60 | wt% | Source cell: .40/.60. Scope: p7, SAE 8640.Ref: Metallus | VERIFIED |
| Nickel | Ni | 28 | RANGE | 0.40 – 0.70 | wt% | Source cell: .40/.70. Scope: p7, SAE 8640.Ref: Metallus | VERIFIED |
| Molybdenum | Mo | 42 | RANGE | 0.15 – 0.25 | wt% | Source cell: .15/.25. Scope: p7, SAE 8640.Ref: Metallus | VERIFIED |
| Silicon | Si | 14 | RANGE | 0.15 – 0.35 | wt% | Source cell: .15/.35. Scope: p7, SAE 8640; p7 default footnote / row override.Ref: Metallus | VERIFIED |
| Phosphorus | P | 15 | MAXIMUM | ≤ 0.04 | wt% | Source cell: .035max. Scope: p7, SAE 8640; p7 default footnote / row override.Ref: Metallus | VERIFIED |
| Sulfur | S | 16 | MAXIMUM | ≤ 0.04 | wt% | Source cell: .040max. Scope: p7, SAE 8640; p7 default footnote / row override.Ref: Metallus | VERIFIED |
Physical Properties
Source-specific physical properties. Test temperatures are shown only where reported.
| Property Parameter | Canonical SI Value | Semantic Basis | Test Temperature / Context Range | Source Raw Reference | Source Reference | Status |
|---|---|---|---|---|---|---|
| Density | 7.85 g/cm³ | TYPICAL | 7.85 g/cm3 | Ovako / Technical Steel Navigator | VERIFIED | |
| Elastic Modulus | 205 GPa | TYPICAL | 205 GPa | Ovako / Technical Steel Navigator | VERIFIED | |
| Poisson's Ratio | 0.29 dimensionless | TYPICAL | 0.29 dimensionless | Ovako / Technical Steel Navigator | VERIFIED |
Thermal & Thermodynamic Properties
Phase change temperatures, thermal conductivity, specific heat, mean coefficients of thermal expansion across standardized temperature ranges, and recommended thermal processing windows.
| Property Parameter | Canonical SI Value | Semantic Basis | Test Temperature / Context Range | Source Raw Reference | Source Reference | Status |
|---|---|---|---|---|---|---|
| Coefficient of Thermal Expansion | 12.1 µm/(m·K) | TYPICAL | Test Temp: 100 °C | 12.1 10^-6/K | Ovako / Technical Steel Navigator | VERIFIED |
| Thermal Conductivity | 46.6 W/(m·K) | TYPICAL | Test Temp: 100 °C | 46.6 W/(m·K) | Ovako / Technical Steel Navigator | VERIFIED |
Contextual Mechanical Properties & Tempers
Engineering strength, ductility, and hardness values grouped by product form, temper, and section thickness. Mechanical properties are contextual and not isotropic averages.
| Product Form | Temper / Condition | Section Size | Tensile (UTS) | Yield Strength | Elongation | Shear Strength | Fatigue Strength | Hardness (Scales Preserved) | Status |
|---|---|---|---|---|---|---|---|---|---|
| Bar | Annealed Bar · AnnealedSource values and qualifiersUltimate Tensile Strength: ≥ 690 MPa (MINIMUM)Ovako / Technical Steel Navigator — Ovako 8640 Datasheet, Mechanical Table Elongation at Break: ≥ 19 % (MINIMUM)Ovako / Technical Steel Navigator — Ovako 8640 Datasheet, Mechanical Table | — | ≥ 690 MPa | — | ≥ 19 % | — | — | — | VERIFIED |
| Bar | Annealed Bar · AnnealedSource values and qualifiersYield Strength: ≥ 415 MPa (MINIMUM)0.2% offsetOvako / Technical Steel Navigator — Ovako 8640 Datasheet, Mechanical Table | — | — | ≥ 415 MPa | — | — | — | — | VERIFIED |
| Bar | Annealed BarSource values and qualifiersHB Hardness: ≤ 217 HB (MAXIMUM)Ovako / Technical Steel Navigator — Ovako 8640 Datasheet, Mechanical Table | — | — | — | — | — | — | ≤ 217 HB | VERIFIED |
Sources & Provenance Trail
Reference publications and standards organization registers cited across this material record.
Reviewed factual transcription; source document SHA-256 is recorded in the capture metadata. No cross-standard equivalence is asserted.
Reviewed factual transcription; source document SHA-256 is recorded in the capture metadata. No cross-standard equivalence is asserted.
Reviewed factual transcription from primary producer engineering datasheet.
Reviewed factual transcription from primary producer engineering datasheet.
Reviewed factual transcription from primary producer engineering datasheet.
Reviewed factual transcription from primary producer engineering datasheet.