Steel 36CrNiMo4 +U (Hot rolled)
Finish state
EN 36CrNiMo4 · BS 816M40
Cheapest mill delivery state for stock that will be forged or fully heat treated later.
Values for the +U condition
Other 36CrNiMo4 tempers and conditions
36CrNiMo4 is listed in 13 conditions; see the grade overview at 36CrNiMo4.
Compare all 13 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Delivery state for bar that will be machined and then heat treated by the customer. | 450 | 760 | 18 | 220 HB | — |
+UThis page Hot rolled | Cheapest mill delivery state for stock that will be forged or fully heat treated later. | 520 | 850 | 14 | 24 HRC | 8 % IACS |
Normalized | Grain-refined, uniform structure for forgings prior to final quench and temper. | 560 | 880 | 15 | 25 HRC | 8 % IACS |
+QT | Largest EN-covered section; choose when part diameter exceeds 160 mm. | 610 | 820 | 16 | 24 HRC | 8 % IACS |
+QT | Heavy forgings and large shafts where mass effect lowers as-quenched hardness. | 660 | 880 | 15 | 27 HRC | 8 % IACS |
Cold drawn | Bright, close-tolerance bar for machined parts where full Q&T strength is not needed. | 720 | 900 | 10 | 26 HRC | 8 % IACS |
Q&TDefault Quenched and tempered | Standard stocked condition: best strength/toughness balance for medium and heavy shafts. | 780 | 1,000 | 14 | 32 HRC | — |
Q&T + gas/plasma nitrided surface | Adds a hard, wear- and fatigue-resistant case on a Q&T core with minimal distortion. | 780 | 1,000 | 13 | 58 HRC | 8 % IACS |
Q&T to 28–32 HRC | Tough, readily machinable hardness band for general shafting and gear blanks. | 800 | 980 | 15 | 30 HRC | 8 % IACS |
+QT | Typical class for medium-diameter shafting and highly loaded fasteners. | 880 | 1,100 | 12 | 36 HRC | 7.8 % IACS |
Q&T to 32–36 HRC | Higher-strength band for heavily loaded shafts and holders still needing decent toughness. | 930 | 1,100 | 12 | 34 HRC | 8 % IACS |
+QT | Highest-strength EN class, for small-diameter bar, bolts and pins. | 980 | 1,200 | 11 | 39 HRC | 7.8 % IACS |
Q&T to 38–42 HRC | Maximum practical strength band; use only for small sections where toughness margin is acceptable. | 1,120 | 1,300 | 10 | 40 HRC | — |
What is 36CrNiMo4 +U?
36CrNiMo4 +U is 36CrNiMo4 supplied in the +U condition — cheapest mill delivery state for stock that will be forged or fully heat treated later. 36CrNiMo4 +U has a yield strength of 520 MPa (75.4 ksi) and a tensile strength of 850 MPa (123 ksi) — stronger than 67% of steel grades. Elongation at break is 14% and the elastic modulus is 210 GPa (30.5 Msi). 36CrNiMo4 +U 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). Q&T is the default condition FabDigit quotes; +U is available on request or by drawing note.
Advantages
- Polishes to a fine finish — 70/100, better than 87% of steel grades
Limitations
- Limited ductility — 14%, worse than 75% of steel grades
- Low fracture toughness — 65 MPa·√m (59.2 ksi·√in), worse than 75% of steel grades
36CrNiMo4 +U properties
Typical room-temperature values for 36CrNiMo4 +U; 22 are specific to this condition. Other listed values are 36CrNiMo4 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
36CrNiMo4 +U 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
36CrNiMo4 +U has a yield strength of 520 MPa (75.4 ksi) and a tensile strength of 850 MPa (123 ksi) — stronger than 67% of steel grades. Elongation at break is 14% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
36CrNiMo4 +U is rated for continuous service to 400°C (752 °F). It conducts heat at 44 W/m·K (25.4 BTU/hr·ft·°F), better than 57% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical2
36CrNiMo4 +U has an electrical resistivity of 2.2×10⁻⁷ Ω·m.
Chemical & Environmental2
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of 36CrNiMo4 +U takes about 32 MJ of energy and emits 2.3 kg of CO₂ — more than 70% of steel grades. Typical recycled content is 30%.
Manufacturability6
36CrNiMo4 +U's machinability is fair (50/100, worse than 53% of steel grades); weldability poor (28/100); formability poor (25/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 36CrNiMo4 +U
Is 36CrNiMo4 easy to machine?
Machine in the annealed or ≤32 HRC condition with rigid setups, carbide tooling and generous coolant; expect ~50 % of AISI 1212 speeds and heavy tool wear above 36 HRC.
Can 36CrNiMo4 be welded?
Weldable only with care: preheat 250–350 °C, low-hydrogen consumables, interpass control and immediate post-weld temper below the last tempering temperature.
Can 36CrNiMo4 be formed, bent or molded?
Hot forge 1100–850 °C then slow cool/normalize; cold forming is limited to the soft-annealed state with generous bend radii.
What surface finishes work on 36CrNiMo4?
Requires protection — oil, phosphate, black oxide, zinc/nickel or hard chrome plating (bake 190–220 °C against hydrogen embrittlement); polishes and nitrides very well.
36CrNiMo4 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 | 0.32 – 0.4 | 0.36 |
| Si | ≤ 0.4 | 0.25 |
| Mn | 0.5 – 0.8 | 0.65 |
| P | ≤ 0.03 | — |
| S≤0.035 for +S variants; ≤0.025 for controlled-sulphur | ≤ 0.04 | — |
| Cr | 0.9 – 1.2 | 1.05 |
| Mo | 0.15 – 0.3 | 0.22 |
| Ni | 0.9 – 1.2 | 1.05 |
| Fe | balance | — |
36CrNiMo4 +U — frequently asked
What is 36CrNiMo4 +U used for?
36CrNiMo4 +U is typically used for forged drive shafts, gears and pinions, crankshafts and connecting rods, heavy axle shafts, aerospace fittings and high-strength bolts and studs. In short: high-strength Ni-Cr-Mo bar.
What is the yield strength of 36CrNiMo4 +U?
36CrNiMo4 +U has a typical yield strength of 520 MPa (75.4 ksi) and a tensile strength of 850 MPa (123 ksi) — stronger than 67% of steel grades. Strength varies by condition: see the 13 listed tempers.
Is 36CrNiMo4 +U easy to machine?
Reasonably — machinability is rated fair (50/100, worse than 53% of steel grades). Machine in the annealed or ≤32 HRC condition with rigid setups, carbide tooling and generous coolant; expect ~50 % of AISI 1212 speeds and heavy tool wear above 36 HRC.
Can 36CrNiMo4 +U be welded?
Not readily — weldability is rated poor (28/100). Weldable only with care: preheat 250–350 °C, low-hydrogen consumables, interpass control and immediate post-weld temper below the last tempering temperature.
What surface finishes work on 36CrNiMo4 +U?
Requires protection — oil, phosphate, black oxide, zinc/nickel or hard chrome plating (bake 190–220 °C against hydrogen embrittlement); polishes and nitrides very well.
Can 36CrNiMo4 +U be formed, bent or molded?
Hot forge 1100–850 °C then slow cool/normalize; cold forming is limited to the soft-annealed state with generous bend radii.
What is the maximum service temperature of 36CrNiMo4 +U?
36CrNiMo4 +U is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Can FabDigit make parts in 36CrNiMo4 +U?
Yes — 36CrNiMo4 +U is available for CNC machining and sheet metal; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.
Sources
- EN 10083-3 Steels for quenching and tempering — Alloy steels — CEN (2006)
- EN 10250-3 Open die steel forgings — Alloy special steels — CEN (1999)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.19 — Fatigue and Fracture — ASM International (1996)
- Engineering steel 1.6511 / 36CrNiMo4 bar datasheet — Ovako / Lucchini RS (2022)
- GB/T 3077 (35CrNiMo comparison) — SAC (2015)
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.