Mat Grades internal verification confirms source-backed fidelity and data integrity. It does not constitute external certification or guaranteed lot conformity. Read engineering disclaimer →
Representative source rows, qualified by their reported conditions. Inspect the tables below for all values, limits, and source notes.
SAE 8622 is a higher carbon Ni-Cr-Mo carburizing steel offering increased core yield and tensile strength for transmission gears, ring gears, and differential pinions.
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 | 8622 | Society of Automotive Engineers | —Ref: Practical Data for Metallurgists, 19th edition |
| AISI | 8622 | American Iron and Steel Institute | —Ref: Practical Data for Metallurgists, 19th edition |
| UNS | G86220 | Unified Numbering System | —Ref: Practical Data for Metallurgists, 19th edition |
| Standards Body | Specification Code | Specification Title / Scope | Relationship Type |
|---|---|---|---|
| SAE | SAE 8622 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 |
|---|---|---|---|---|---|---|---|
| Iron | Fe | 26 | BALANCE | Balance | wt% | Ref: Metallus | VERIFIED |
| Carbon | C | 6 | RANGE | 0.20 – 0.25 | wt% | Ref: Metallus | VERIFIED |
| Manganese | Mn | 25 | RANGE | 0.70 – 0.90 | wt% | Ref: Metallus | VERIFIED |
| Phosphorus | P | 15 | MAXIMUM | ≤ 0.03 | wt% | Ref: Metallus | VERIFIED |
| Sulfur | S | 16 | MAXIMUM | ≤ 0.04 | wt% | Ref: Metallus | VERIFIED |
| Silicon | Si | 14 | RANGE | 0.15 – 0.35 | wt% | Ref: Metallus | VERIFIED |
| Chromium | Cr | 24 | RANGE | 0.40 – 0.60 | wt% | Ref: Metallus | VERIFIED |
| Nickel | Ni | 28 | RANGE | 0.40 – 0.70 | wt% | Ref: Metallus | VERIFIED |
| Molybdenum | Mo | 42 | RANGE | 0.15 – 0.25 | wt% | 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 | Metallus | VERIFIED | |
| Elastic Modulus | 205 GPa | TYPICAL | 205 GPa | Metallus | VERIFIED | |
| Poisson's Ratio | 0.29 dimensionless | TYPICAL | 0.29 dimensionless | Metallus | 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 |
|---|---|---|---|---|---|---|
| Specific Heat Capacity | 486 J/(kg·K) | TYPICAL | 486 J/(kg·K) | Metallus | VERIFIED | |
| Thermal Conductivity | 42.6 W/(m·K) | TYPICAL | 42.6 W/(m·K) | Metallus | 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 (25 mm)Source values and qualifiersUltimate Tensile Strength: ≥ 590 MPa (MINIMUM)ASTM A108 / ASTM E8Metallus — p118, Estimated Minimum Properties for Cold Drawn Bars Reduction of Area: ≥ 45 % (MINIMUM)ASTM A108 / ASTM E8Metallus — p118, Estimated Minimum Properties for Cold Drawn Bars | — | ≥ 590 MPa | — | — | — | — | — | VERIFIED |
| Bar | Normalized Bar (25 mm)Source values and qualifiersYield Strength: ≥ 390 MPa (MINIMUM)ASTM A108 / ASTM E8 (0.2% offset)Metallus — p118, Estimated Minimum Properties for Cold Drawn Bars | — | — | ≥ 390 MPa | — | — | — | — | VERIFIED |
| Bar | Normalized Bar (25 mm)Source values and qualifiersElongation at Break: ≥ 19 % (MINIMUM)ASTM A108 / ASTM E8Metallus — p118, Estimated Minimum Properties for Cold Drawn Bars | — · in 50 mm (2 in) | — | — | ≥ 19 % | — | — | — | VERIFIED |
| Bar | Normalized Bar (25 mm)Source values and qualifiersHB Hardness: ≤ 201 HB (TYPICAL)Metallus — p118, Estimated Minimum Properties for Cold Drawn Bars | — | — | — | — | — | — | ≤ 201 HB | VERIFIED |
By Mat Grades Editorial Desk · Updated 2026-11-14. Use alongside the specified product standard and supplier certificate.
For SAE 8622 Alloy Steel, a qualified cutting-speed or tool-life recommendation is not supplied in the available record. A relevant hardness example is HB Hardness: maximum 201 HB (typical; Normalized Bar (25 mm), 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 590 MPa (minimum; Normalized Bar (25 mm), 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 Thermal Conductivity: 42.6 W/(m·K) (typical; additional condition not stated). 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 0.2–0.25 wt%, Mn 0.7–0.9 wt%. Chemistry documents identity; it does not establish fluid compatibility.
Use SAE 8622, AISI 8622, UNS G86220 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 related candidate SAE 8620 Alloy Steel is linked for comparison; its commonly compared relationship must be checked before substitution. 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: Metallus
Comparable Grades & Cross-References: Carefully classified cross-reference relationships for SAE 8622 Alloy Steel. Comparable does not mean equivalent.
| Related Material | Family | Relationship Classification | Metallurgical Notes & Differences | Status | Action |
|---|---|---|---|---|---|
| SAE 8620 Alloy Steel | Steel | Commonly Compared | Higher carbon companion to 8620 for increased core strength in heavy-duty automotive drive gears and transmission components.Materials serve different design priorities (e.g. higher strength vs superior corrosion resistance or cost). | VERIFIED |
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 8622 Alloy Steel.
Cast iron is an indispensable alloy family renowned for superior vibration damping and castability, but its iron matrix and carbon microstructure make it susceptible to atmospheric rust. Restoring rusted cast iron requires understanding how mechanical and chemical methods interact with the underlying metal.
Sources & Provenance Trail: Authoritative reference publications, standards specifications, and data registers cited across this material record.
Reviewed factual transcription from primary producer engineering technical literature.
Reviewed factual transcription from primary producer engineering technical literature.
Reviewed factual transcription from primary producer engineering technical literature.
Reviewed factual transcription from primary producer engineering technical literature.