Steel 8617
AISI/SAE 8617 · UNS G86170
8617 is a nickel-chromium-molybdenum carburizing steel (UNS G86170) carrying slightly more carbon than 8615, which gives a marginally deeper case with good core toughness for medium-duty gearing.
Reference datasheet — 8617 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 Annealed condition
8617 tempers and conditions
8617 is supplied in 8 conditions, soft to hard. Annealed 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 |
|---|---|---|---|---|---|---|
for cold heading / cold extrusion | Pick when parts are cold-formed (headed, extruded) before carburizing; lowest hardness and best cold ductility. | 330 | 480 | 34 | 137 HB | 7.8 % IACS |
as-rolled bar | Cheapest mill condition for large forging/gear blanks that will be normalized or annealed before machining. | 340 | 560 | 27 | 163 HB | 7.8 % IACS |
AnnealedDefault full anneal, soft machinable bar | Standard stock condition for gear blanks: softest, most machinable, ready for carburizing after rough machining. | 360 | 515 | 31 | 149 HB | — |
900–925 °C air cool | Use to homogenize forgings and refine grain before carburizing; best combination of core strength and machinability. | 375 | 610 | 27 | 179 HB | — |
annealed and cold finished bar | Choose for small shafts and pins needing tight tolerance and good surface straight from bar, with higher as-supplied strength. | 500 | 600 | 18 | 179 HB | — |
Through-hardened | Direct oil quench and high temper when a tough uniform core is wanted without a case (shafts, arbors, fixtures). | 750 | 950 | 18 | 30 HRC | — |
thin hard case on small parts | Lower-temperature alternative to carburizing for small pins, washers and light gears where distortion must be minimized. | 780 | 1,000 | 13 | 59 HRC | 7.5 % IACS |
case 58–62 HRC / core ~30–40 HRC | The service condition for gears and pins: hard wear/pitting-resistant case with high compressive residual stress over a tough core. | 850 | 1,100 | 12 | 60 HRC | — |
What is 8617?
8617 is a nickel-chromium-molybdenum carburizing steel (UNS G86170) carrying slightly more carbon than 8615, which gives a marginally deeper case with good core toughness for medium-duty gearing. Bar and forging stock are available annealed, spheroidize annealed, hot-rolled, normalized, cold-drawn, Q&T to 28-32 HRC, carburized and quenched-and-tempered, or carbonitrided; the annealed condition runs about 360 MPa yield, 515 MPa tensile, 31 % elongation and 149 HB (80 HRB). Machinability is around 65 % of 1212 and carburized cases must not be welded, so joints are designed before heat treatment; 8620 is the more widely stocked substitute. 8617 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). 8617 has a yield strength of 360 MPa (52.2 ksi) and a tensile strength of 515 MPa (74.7 ksi) — weaker than 72% of steel grades. Elongation at break is 31% and the elastic modulus is 205 GPa (29.7 Msi).
What is 8617 used for?
- gears
- shafts
- bushings
- camshafts
Advantages
- Ductile — tolerates forming and impact — 31%, better than 94% of steel grades
- Low embodied carbon — 1.9 kg CO₂/kg, better than 92% of steel grades
- Forms and bends easily — 65/100, better than 81% of steel grades
Limitations
- Limited service temperature — 300°C (572 °F), worse than 78% of steel grades
8617 properties
Typical room-temperature values for 8617-Annealed; bars are the position among steel grades.
Physical3
8617 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
8617 has a yield strength of 360 MPa (52.2 ksi) and a tensile strength of 515 MPa (74.7 ksi) — weaker than 72% of steel grades. Elongation at break is 31% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
8617 is rated for continuous service to 300°C (572 °F). It conducts heat at 44 W/m·K (25.4 BTU/hr·ft·°F), better than 57% of steel grades. Thermal expansion is 11.5 µm/m·K (6.39 µin/in·°F).
Electrical3
8617 conducts electricity at 7.8 % IACS, worse than 57% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (10/100), worse than 86% of steel grades.
Sustainability4
Producing a kilogram of 8617 takes about 25 MJ of energy and emits 1.9 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 30%.
Manufacturability8
8617's machinability is good (60/100, better than 83% of steel grades); weldability good (60/100); formability good (65/100).
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. 8617 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 8617
Is 8617 easy to machine?
Machine in the annealed or normalized state (≈65 % of 1212) with carbide at ~120–170 m/min; leave 0.2–0.5 mm grind stock for post-carburizing distortion.
Can 8617 be welded?
Weldable with low-hydrogen consumables at 150–250 °C preheat and post-weld stress relief; do not weld after carburizing.
Can 8617 be formed, bent or molded?
Good hot forgeability at 1100–1200 °C and acceptable cold heading when spheroidize annealed; normalize forgings before case hardening.
8617 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 J404 heat analysis | 0.15 – 0.2 | 0.17 |
| 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; 8617H/resulfurized variants differ | ≤ 0.04 | |
| Fe | balance |
What surface finishes work on 8617?
Gas carburize 900–930 °C, oil quench, temper 150–200 °C, then grind; protect uncarburized surfaces with copper plate or stop-off paint and finish with black oxide, phosphate or zinc plating.
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 8617 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- G86170
How much does 8617 cost?
8617 is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
8617 — frequently asked
What is 8617 used for?
8617 is typically used for gears, shafts, bushings and camshafts. In short: deeper case than 8615; medium-duty gear steel; tough Ni-Cr-Mo core.
What is the yield strength of 8617?
8617 has a typical yield strength of 360 MPa (52.2 ksi) and a tensile strength of 515 MPa (74.7 ksi) — weaker than 72% of steel grades. Strength varies by condition: see the 8 listed tempers.
Is 8617 easy to machine?
Reasonably — machinability is rated good (60/100, better than 83% of steel grades). Machine in the annealed or normalized state (≈65 % of 1212) with carbide at ~120–170 m/min; leave 0.2–0.5 mm grind stock for post-carburizing distortion.
Can 8617 be welded?
Yes — weldability is rated good (60/100). Weldable with low-hydrogen consumables at 150–250 °C preheat and post-weld stress relief; do not weld after carburizing.
What surface finishes work on 8617?
Gas carburize 900–930 °C, oil quench, temper 150–200 °C, then grind; protect uncarburized surfaces with copper plate or stop-off paint and finish with black oxide, phosphate or zinc plating.
Can 8617 be formed, bent or molded?
Good hot forgeability at 1100–1200 °C and acceptable cold heading when spheroidize annealed; normalize forgings before case hardening.
What is the maximum service temperature of 8617?
8617 is rated for continuous use to about 300°C (572 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does 8617 cost?
8617 is a budget-cost steel ($), 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 — 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) — ASM International (1991)
- SAE J1268 — Hardenability Bands for Carbon and Alloy H Steels (8617H) — SAE International (2019)
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.