Heat Treatment Basics: Annealing, Normalizing, Quenching and Tempering
Understand the purpose of each operation before specifying a steel heat-treatment route.
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Representative source rows, qualified by their reported conditions. Inspect the tables below for all values, limits, and source notes.
SAE 8620 Alloy Steel. Source-scoped engineering data is shown with its reported limits and conditions. Unreported properties are not inferred.
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 | 8620 | SAE | —Ref: Practical Data for Metallurgists, 19th edition |
| Standards Body | Specification Code | Specification Title / Scope | Relationship Type |
|---|---|---|---|
| SAE | SAE 8620 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 | 0.18 – 0.23 | wt% | Source cell: .18/.23. Scope: p7, SAE 8620.Ref: Metallus | VERIFIED |
| Manganese | Mn | 25 | RANGE | 0.70 – 0.90 | wt% | Source cell: .70/.90. Scope: p7, SAE 8620.Ref: Metallus | VERIFIED |
| Chromium | Cr | 24 | RANGE | 0.40 – 0.60 | wt% | Source cell: .40/.60. Scope: p7, SAE 8620.Ref: Metallus | VERIFIED |
| Nickel | Ni | 28 | RANGE | 0.40 – 0.70 | wt% | Source cell: .40/.70. Scope: p7, SAE 8620.Ref: Metallus | VERIFIED |
| Molybdenum | Mo | 42 | RANGE | 0.15 – 0.25 | wt% | Source cell: .15/.25. Scope: p7, SAE 8620.Ref: Metallus | VERIFIED |
| Silicon | Si | 14 | RANGE | 0.15 – 0.35 | wt% | Source cell: .15/.35. Scope: p7, SAE 8620; p7 default footnote / row override.Ref: Metallus | VERIFIED |
| Phosphorus | P | 15 | MAXIMUM | ≤ 0.04 | wt% | Source cell: .035max. Scope: p7, SAE 8620; p7 default footnote / row override.Ref: Metallus | VERIFIED |
| Sulfur | S | 16 | MAXIMUM | ≤ 0.04 | wt% | Source cell: .040max. Scope: p7, SAE 8620; p7 default footnote / row override.Ref: Metallus | VERIFIED |
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 |
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 | Normalized Bar (870°C) - Core Properties · Normalized 870°C air cooledSource values and qualifiersUltimate Tensile Strength: ≥ 630 MPa (MINIMUM)Core mechanical properties. Case hardening properties require a specified carburizing and quenching cycle.ASTM A29Ovako / Technical Steel Navigator — Ovako 8620 Datasheet, Core Properties Table Reduction of Area: ≥ 50 % (MINIMUM)ASTM A29Ovako / Technical Steel Navigator — Ovako 8620 Datasheet, Core Properties Table | — | ≥ 630 MPa | — | — | — | — | — | VERIFIED |
| Bar | Normalized Bar (870°C) - Core Properties · Normalized 870°C air cooledSource values and qualifiersYield Strength: ≥ 380 MPa (MINIMUM)Core mechanical properties.ASTM A29 (0.2% offset)Ovako / Technical Steel Navigator — Ovako 8620 Datasheet, Core Properties Table | — | — | ≥ 380 MPa | — | — | — | — | VERIFIED |
| Bar | Normalized Bar (870°C) - Core Properties · Normalized 870°C air cooledSource values and qualifiersElongation at Break: ≥ 20 % (MINIMUM)ASTM A29Ovako / Technical Steel Navigator — Ovako 8620 Datasheet, Core Properties Table | — · in 50 mm (2 in) | — | — | ≥ 20 % | — | — | — | VERIFIED |
| Bar | Normalized Bar (870°C) - Core PropertiesSource values and qualifiersHB Hardness: ≥ 179 HB (MINIMUM)Ovako / Technical Steel Navigator — Ovako 8620 Datasheet, Core Properties Table | — | — | — | — | — | — | ≥ 179 HB | VERIFIED |
By Mat Grades Editorial Desk · Updated 2026-11-14. Use alongside the specified product standard and supplier certificate.
For SAE 8620 Alloy Steel, a qualified cutting-speed or tool-life recommendation is not supplied in the available record. A relevant hardness example is HB Hardness: minimum 179 HB (minimum; Normalized Bar (870°C) - Core Properties, Bar). Use that supplied condition for a trial of the difficult feature. Record tool changes, burr removal, unclamped dimensions and accepted parts per hour. Relative machinability ratings from different reference scales should not be compared as if they were one common test.
No qualified weld procedure, filler selection or preheat/interpass schedule is established by this material record. Obtain a procedure for the actual joint, supplied condition and section rather than copying one from a nearby grade. The first cataloged strength example is Ultimate Tensile Strength: minimum 630 MPa (minimum; Normalized Bar (870°C) - Core Properties, Bar). Assess the final part after joining or thermal processing. Include distortion, cleanup and inspection in the quotation. A material designation or favorable process rating is a starting point for qualification, not evidence that an untested joint meets the drawing.
Plan corrosion protection and inspect how the finish affects threads, bearing fits and repaired surfaces. A steel strength value does not establish corrosion life. Where cyclic load or impact matters, retain the surface condition and the required toughness evidence with the material decision. The recorded thermal example is Coefficient of Thermal Expansion: 12.1 µm/(m·K) (typical; ; test temperature 100 °C). State the exposure and inspection access in the design record so that a change of installation or cleaning method triggers a review. The selected composition entries are C 0.18–0.23 wt%, Mn 0.7–0.9 wt%, Cr 0.4–0.6 wt%. Chemistry documents identity; it does not establish fluid compatibility.
Use SAE 8620, SPECIFICATION SAE 8620 Alloy Steel Engineering Datasheet to identify the candidate, then specify the product form and delivered condition separately. A specific component application is not asserted where the source record does not provide one. The listed forms include Bar; confirm the actual stock offered by the supplier. Compare the complete route through machining, joining, finish and inspection. Keep the certificate, required test location and acceptance criteria with the first-article record. A later change of grade, condition or source should be assessed against that same requirement.
Technical references: Ovako / Technical Steel Navigator; Metallus
Triple-alloy Ni-Cr-Mo steels engineered for high core toughness and predictable hardenability in heavy-duty transmission components.
Contextual technical guides explaining degradation mechanisms, testing methodologies, and selection criteria relevant to SAE 8620 Alloy Steel.
Understand the purpose of each operation before specifying a steel heat-treatment route.
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Sources & Provenance Trail: Authoritative reference publications, standards specifications, and data 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.