Steel 8615
AISI/SAE 8615 · UNS G86150
8615 is a nickel-chromium-molybdenum case-hardening steel (AISI/SAE 8615, UNS G86150) with lower alloy content than 8620, intended for lighter-duty carburized components.
Reference datasheet — 8615 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the HR condition
8615 tempers and conditions
8615 is supplied in 8 conditions, soft to hard. HR is the default FabDigit quotes; the values on this page are for it.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution annealed | Softest condition, best for deep machining, cold forming and gear blanking before carburizing. | 340 | 515 | 32 | 149 HB | — |
HRDefault Hot rolled | Standard mill-stock condition for carburizing bar; machine to shape then carburize and harden. | 360 | 585 | 27 | 174 HB | 7.8 % IACS |
Normalized | Uniform fine-grain structure and predictable machining response before carburizing; better core toughness than as-rolled. | 365 | 600 | 28 | 174 HB | — |
Stress relieved | Applied to cold-drawn or heavily machined blanks to reduce distortion during subsequent carburizing. | 450 | 600 | 22 | 180 HB | 7.8 % IACS |
Cold drawn | Tight tolerance, bright surface, higher yield strength for pins, shafts and screw-machine parts. | 550 | 655 | 15 | 197 HB | — |
Quenched and tempered | Used when a tough medium-strength part is wanted without a case; oil quench from ~855 °C, temper 200–540 °C. | 690 | 900 | 18 | 28 HRC | — |
core properties (25–35 HRC core) | Reference core data for design calculations of carburized 8615 parts in light/medium sections. | 690 | 930 | 16 | 30 HRC | 7.3 % IACS |
Carburized, hardened and tempered | Production condition for gears, sprockets and cams: hard wear-resistant case with tough low-carbon core and high bending fatigue strength. | 700 | 950 | 12 | 60 HRC | — |
What is 8615?
8615 is a nickel-chromium-molybdenum case-hardening steel (AISI/SAE 8615, UNS G86150) with lower alloy content than 8620, intended for lighter-duty carburized components. It is used for small gears, shafts and pins and is stocked annealed, normalized, hot-rolled, cold-drawn, quenched-and-tempered, stress-relieved, or carburized to a 58–62 HRC case. Default-condition values are 360 MPa yield, 585 MPa tensile, 27 % elongation and 174 HB, with a machinability score of 62. Core strength and hardenability are below 8620 or 8622, and the steel needs a coating for corrosion protection. 8615 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,420°C (2,588 °F). 8615 has a yield strength of 360 MPa (52.2 ksi) and a tensile strength of 585 MPa (84.8 ksi) — weaker than 72% of steel grades. Elongation at break is 27% and the elastic modulus is 205 GPa (29.7 Msi).
What is 8615 used for?
- small gears
- shafts
- pins
Advantages
- Easy to machine — 62/100, better than 89% of steel grades
- Ductile — tolerates forming and impact — 27%, better than 86% of steel grades
Limitations
- Limited service temperature — 300°C (572 °F), worse than 78% of steel grades
8615 properties
Typical room-temperature values for 8615-HR; bars are the position among steel grades.
Physical3
8615 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,420°C (2,588 °F).
Mechanical16
8615 has a yield strength of 360 MPa (52.2 ksi) and a tensile strength of 585 MPa (84.8 ksi) — weaker than 72% of steel grades. Elongation at break is 27% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
8615 is rated for continuous service to 300°C (572 °F). It conducts heat at 46 W/m·K (26.6 BTU/hr·ft·°F), better than 71% of steel grades. Thermal expansion is 11.5 µm/m·K (6.39 µin/in·°F).
Electrical3
8615 conducts electricity at 7.8 % IACS, worse than 57% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of 8615 takes about 26 MJ of energy and emits 2.1 kg of CO₂ — less than 64% of steel grades. Typical recycled content is 30%.
Manufacturability7
8615's machinability is good (62/100, better than 89% of steel grades); weldability good (60/100); formability good (55/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the steel family
Yield strength against density for every steel grade FabDigit runs. 8615 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 8615
Is 8615 easy to machine?
Machines well in annealed/normalized or cold-drawn state (~65 % of 1212); finish-machine before carburizing and allow only grinding after case hardening.
Can 8615 be welded?
Weldable in the low-carbon soft condition with low-hydrogen consumables and 150–250 °C preheat; do not weld carburized surfaces and stress relieve after welding.
Can 8615 be formed, bent or molded?
Good cold formability and forgeability in the annealed condition (forge 1100–1230 °C, slow cool then normalize/anneal); carburize 900–930 °C, oil quench from 815–855 °C, temper 150–200 °C.
8615 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| CSAE 8615 / UNS G86150 | 0.13 – 0.18 | 0.16 |
| Mn | 0.7 – 0.9 | 0.8 |
| Si | 0.15 – 0.35 | 0.25 |
| Ni | 0.4 – 0.7 | 0.55 |
| Cr | 0.4 – 0.6 | 0.5 |
| Mo | 0.15 – 0.25 | 0.2 |
| P | ≤ 0.04 | |
| Smax; H-grade and resulfurized variants differ | ≤ 0.04 | |
| Fe | balance |
What surface finishes work on 8615?
No anodizing; protect with oil, phosphate, black oxide, zinc or nickel plating — bake plated parts to avoid hydrogen embrittlement; case-hardened surfaces are typically ground and shot-peened for fatigue.
Surface treatments FabDigit runs on steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Organic Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Steel 8615 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- G86150
How much does 8615 cost?
8615 is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
8615 — frequently asked
What is 8615 used for?
8615 is typically used for small gears, shafts and pins. In short: leaner, cheaper than 8620; best-machining 86xx carburizer; light-duty gear steel.
What is the yield strength of 8615?
8615 has a typical yield strength of 360 MPa (52.2 ksi) and a tensile strength of 585 MPa (84.8 ksi) — weaker than 72% of steel grades. Strength varies by condition: see the 8 listed tempers.
Is 8615 easy to machine?
Reasonably — machinability is rated good (62/100, better than 89% of steel grades). Machines well in annealed/normalized or cold-drawn state (~65 % of 1212); finish-machine before carburizing and allow only grinding after case hardening.
Can 8615 be welded?
Yes — weldability is rated good (60/100). Weldable in the low-carbon soft condition with low-hydrogen consumables and 150–250 °C preheat; do not weld carburized surfaces and stress relieve after welding.
What surface finishes work on 8615?
No anodizing; protect with oil, phosphate, black oxide, zinc or nickel plating — bake plated parts to avoid hydrogen embrittlement; case-hardened surfaces are typically ground and shot-peened for fatigue.
Can 8615 be formed, bent or molded?
Good cold formability and forgeability in the annealed condition (forge 1100–1230 °C, slow cool then normalize/anneal); carburize 900–930 °C, oil quench from 815–855 °C, temper 150–200 °C.
What is the maximum service temperature of 8615?
8615 is rated for continuous use to about 300°C (572 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 8615-HR and 8615-CD?
HR is the default condition — standard mill-stock condition for carburizing bar; machine to shape then carburize and harden. CD: tight tolerance, bright surface, higher yield strength for pins, shafts and screw-machine parts. Yield strength is 360 MPa in HR versus 550 MPa in CD.
How much does 8615 cost?
8615 is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- SAE J404 — Chemical Compositions of SAE Alloy Steels — SAE International (2021)
- ASTM A29/A29M — General Requirements for Steel Bars, Carbon and Alloy, Hot-Wrought — ASTM (2020)
- ASTM A322 — Steel Bars, Alloy, Standard Grades — ASTM (2020)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.4 — Heat Treating (carburizing practice) — ASM International (1991)
- ASM Handbook Vol.16 — Machining — ASM International (1989)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.