Steel 20NiCrMo2-2 +FP
Heat-treated state · default condition
EN 20NiCrMo2-2 · GB 20CrNiMo
+FP = treated to ferrite-pearlite structure
Standard machining stock for carburized gears: uniform F-P microstructure gives repeatable cutting and low distortion in the later carburize cycle.
Values for the +FP condition
Other 20NiCrMo2-2 tempers and conditions
20NiCrMo2-2 is listed in 8 conditions; see the grade overview at 20NiCrMo2-2.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Spheroidize annealed | Pick for maximum softness/ductility before cold forming, deep drawing or cold heading of blanks that will later be carburized. | 320 | 510 | 24 | 160 HB | — |
+FPDefaultThis page Treated to ferrite-pearlite structure | Standard machining stock for carburized gears: uniform F-P microstructure gives repeatable cutting and low distortion in the later carburize cycle. | 355 | 580 | 20 | 165 HB | — |
Normalized | Normalizing refines grain and homogenizes forged or hot-rolled stock before rough machining and carburizing. | 360 | 630 | 26 | 183 HB | — |
Treated to a specified hardness range | Choose when the shop needs a narrow as-delivered hardness window for CNC/broaching productivity rather than a defined microstructure. | 400 | 640 | 17 | 11 HRC | 8 % IACS |
Treated for cold shearing | Delivery condition for coil/bar that will be cold sheared or cropped into blanks without cracking. | 420 | 600 | 16 | 11 HRC | 8 % IACS |
Spheroidized annealed then cold drawn | Bright cold-drawn bar: tight tolerance and higher as-delivered strength for automatic-lathe parts (pins, shafts) that need little pre-machining. | 550 | 660 | 11 | 200 HB | — |
Hardenability-controlled bar, hardened and tempered | Order +H when the Jominy band must be guaranteed; values here are for the direct-hardened and low-tempered condition (core of a carburized part or a through-hardened small section). | 800 | 1,100 | 12 | 36 HRC | — |
Carburized, quenched and low-temperature tempered | The end-use condition: 0.4–1.5 mm case at 58–62 HRC over a tough 30–40 HRC core for gear teeth, splines and cam followers. | 850 | 1,150 | 10 | 60 HRC | — |
What is 20NiCrMo2-2 +FP?
20NiCrMo2-2 +FP is 20NiCrMo2-2 heat treated to +FP — standard machining stock for carburized gears: uniform F-P microstructure gives repeatable cutting and low distortion in the later carburize cycle. 20NiCrMo2-2 +FP has a yield strength of 355 MPa (51.5 ksi) and a tensile strength of 580 MPa (84.1 ksi) — weaker than 73% of steel grades. Elongation at break is 20% and the elastic modulus is 207 GPa (30 Msi). 20NiCrMo2-2 +FP 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).
Advantages
- Easy to machine — 62/100, better than 89% of steel grades
20NiCrMo2-2 +FP properties
Typical room-temperature values for 20NiCrMo2-2 +FP; 14 are specific to this condition. Other listed values are 20NiCrMo2-2 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
20NiCrMo2-2 +FP 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).
Mechanical14
20NiCrMo2-2 +FP has a yield strength of 355 MPa (51.5 ksi) and a tensile strength of 580 MPa (84.1 ksi) — weaker than 73% of steel grades. Elongation at break is 20% and the elastic modulus is 207 GPa (30 Msi).
Thermal6
20NiCrMo2-2 +FP is rated for continuous service to 350°C (662 °F). It conducts heat at 44 W/m·K (25.4 BTU/hr·ft·°F), better than 57% of steel grades. Thermal expansion is 11.6 µm/m·K (6.44 µin/in·°F).
Electrical3
20NiCrMo2-2 +FP conducts electricity at 8 % IACS, better than 55% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of 20NiCrMo2-2 +FP takes about 31 MJ of energy and emits 2.2 kg of CO₂ — more than 64% of steel grades. Typical recycled content is 30%.
Manufacturability7
20NiCrMo2-2 +FP's machinability is good (62/100, better than 89% of steel grades); weldability good (55/100); formability good (55/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 20NiCrMo2-2 +FP
Is 20NiCrMo2-2 easy to machine?
Machines well in +FP/+TH at ~65 % of AISI 1212 — carbide inserts, 120–180 m/min turning; leave 0.2–0.4 mm grinding stock for post-carburizing finishing since the 60 HRC case must be ground, not cut.
Can 20NiCrMo2-2 be welded?
Weldable before carburizing with low-hydrogen consumables, 150–250 °C preheat and stress relief; never weld a carburized surface (case cracking, hydrogen embrittlement).
Can 20NiCrMo2-2 be formed, bent or molded?
Cold head, roll or upset in the +AC spheroidized condition; hot forge 1100–1200 °C, finish above 900 °C, then normalize or isothermally anneal before machining.
What surface finishes work on 20NiCrMo2-2?
No natural corrosion protection — phosphate + oil, black oxide, zinc or zinc-nickel plating (bake to avoid hydrogen embrittlement above 30 HRC); shot peening after carburizing raises gear tooth bending fatigue significantly.
20NiCrMo2-2 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 |
|---|---|---|
| C | 0.17 – 0.23 | 0.2 |
| Simax per EN 10084 | ≤ 0.4 | 0.25 |
| Mn | 0.6 – 0.95 | 0.8 |
| P | ≤ 0.03 | — |
| Smax; 0.020–0.040 for machinability grade +S variants | ≤ 0.04 | — |
| Cr | 0.35 – 0.7 | 0.5 |
| Mo | 0.15 – 0.25 | 0.2 |
| Ni | 0.4 – 0.7 | 0.55 |
| Fe | balance | — |
20NiCrMo2-2 +FP — frequently asked
What is 20NiCrMo2-2 +FP used for?
20NiCrMo2-2 +FP is typically used for gears, shafts, pins and carburized machine parts. In short: european 8620 equivalent; workhorse carburizing steel; good soft-state machinability.
What is the yield strength of 20NiCrMo2-2 +FP?
20NiCrMo2-2 +FP has a typical yield strength of 355 MPa (51.5 ksi) and a tensile strength of 580 MPa (84.1 ksi) — weaker than 73% of steel grades. Strength varies by condition: see the 8 listed tempers.
Is 20NiCrMo2-2 +FP easy to machine?
Reasonably — machinability is rated good (62/100, better than 89% of steel grades). Machines well in +FP/+TH at ~65 % of AISI 1212 — carbide inserts, 120–180 m/min turning; leave 0.2–0.4 mm grinding stock for post-carburizing finishing since the 60 HRC case must be ground, not cut.
Can 20NiCrMo2-2 +FP be welded?
Yes — weldability is rated good (55/100). Weldable before carburizing with low-hydrogen consumables, 150–250 °C preheat and stress relief; never weld a carburized surface (case cracking, hydrogen embrittlement).
What surface finishes work on 20NiCrMo2-2 +FP?
No natural corrosion protection — phosphate + oil, black oxide, zinc or zinc-nickel plating (bake to avoid hydrogen embrittlement above 30 HRC); shot peening after carburizing raises gear tooth bending fatigue significantly.
Can 20NiCrMo2-2 +FP be formed, bent or molded?
Cold head, roll or upset in the +AC spheroidized condition; hot forge 1100–1200 °C, finish above 900 °C, then normalize or isothermally anneal before machining.
What is the maximum service temperature of 20NiCrMo2-2 +FP?
20NiCrMo2-2 +FP is rated for continuous use to about 350°C (662 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- EN 10084 — Case hardening steels: technical delivery conditions — CEN (2008)
- SAE J404 / J1268 — Chemical compositions and hardenability of SAE alloy steels (8620/8620H) — SAE International (2020)
- GB/T 3077 — Alloy structural steels (20CrNiMo) — SAC (2015)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.4A — Steel Heat Treating Fundamentals and Processes (carburizing) — ASM International (2013)
- ASM Handbook Vol.19 — Fatigue and Fracture — ASM International (1996)
- Case-hardening steel 1.6523 / 20NiCrMo2-2 bar datasheet — European special-steel producers (e.g. Ovako / Deutsche Edelstahlwerke) (2022)
- 20CrNiMo — Mysteel / SMM / 1688 (2025)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.