Steel 36NiCrMo16 +QT-40 (+QT)
Heat-treated state · default condition
EN 36NiCrMo16
Standard stocked condition for bar and small forgings; the usual specification reference for this grade.
Values for the +QT-40 condition
Other 36NiCrMo16 tempers and conditions
36NiCrMo16 is listed in 9 conditions; see the grade overview at 36NiCrMo16.
Compare all 9 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Pick for machining, deep drilling or cold straightening of bar before final quench and temper. | 520 | 800 | 16 | 21 HRC | — |
+QT | Heavy forgings and thick shafts — the section size where this grade's nickel content really pays off versus 34CrNiMo6. | 860 | 1,100 | 13 | 35 HRC | — |
+QT | Medium-section shafts and gear blanks where 900 MPa minimum yield with better toughness is wanted. | 960 | 1,200 | 12 | 38 HRC | — |
Normalized | Rarely supplied as a delivery condition — the 4 % Ni gives air-hardening, so a normalise leaves a hard martensitic/bainitic structure needing tempering. | 1,050 | 1,450 | 9 | 46 HRC | 5.4 % IACS |
+QT then gas/plasma nitrided | Use where a wear- and fatigue-resistant surface is needed on a tough high-strength core (gears, spindles, hydraulic rods). | 1,050 | 1,250 | 11 | 58 HRC | 5.7 % IACS |
+QT-40DefaultThis page +QT | Standard stocked condition for bar and small forgings; the usual specification reference for this grade. | 1,120 | 1,330 | 11 | 42 HRC | — |
+SH / peeled-turned bar in +QT condition | Q&T bar supplied peeled and straightened to close tolerance with a decarb-free surface for direct machining. | 1,120 | 1,330 | 11 | 42 HRC | 5.7 % IACS |
+QT | Small-diameter bar for highly stressed bolts, pins and shafts at the top strength class. | 1,150 | 1,350 | 10 | 43 HRC | — |
Q&T low-temper | Choose for ultra-high-strength aerospace/landing-gear-type parts; toughness and hydrogen sensitivity become the design drivers. | 1,400 | 1,600 | 9 | 48 HRC | — |
What is 36NiCrMo16 +QT-40?
36NiCrMo16 +QT-40 is 36NiCrMo16 heat treated to +QT-40 — standard stocked condition for bar and small forgings; the usual specification reference for this grade. 36NiCrMo16 +QT-40 has a yield strength of 1,120 MPa (162 ksi) and a tensile strength of 1,330 MPa (193 ksi) — stronger than 93% of steel grades. Elongation at break is 11% and the elastic modulus is 205 GPa (29.7 Msi). 36NiCrMo16 +QT-40 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
- High strength — 1,120 MPa (162 ksi), better than 93% of steel grades
- Polishes to a fine finish — 70/100, better than 87% of steel grades
Limitations
- Limited ductility — 11%, worse than 89% of steel grades
- Difficult to machine — 30/100, worse than 89% of steel grades
- Limited formability — 15/100, worse than 87% of steel grades
- Difficult to weld — 20/100, worse than 84% of steel grades
- High embodied carbon — 2.5 kg CO₂/kg, worse than 82% of steel grades
36NiCrMo16 +QT-40 properties
Typical room-temperature values for 36NiCrMo16 +QT-40; 13 are specific to this condition. Other listed values are 36NiCrMo16 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
36NiCrMo16 +QT-40 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
36NiCrMo16 +QT-40 has a yield strength of 1,120 MPa (162 ksi) and a tensile strength of 1,330 MPa (193 ksi) — stronger than 93% of steel grades. Elongation at break is 11% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
36NiCrMo16 +QT-40 is rated for continuous service to 350°C (662 °F). It conducts heat at 34 W/m·K (19.6 BTU/hr·ft·°F), worse than 77% of steel grades. Thermal expansion is 11.8 µm/m·K (6.56 µin/in·°F).
Electrical3
36NiCrMo16 +QT-40 conducts electricity at 5.7 % IACS, worse than 80% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (13/100), better than 66% of steel grades.
Sustainability4
Producing a kilogram of 36NiCrMo16 +QT-40 takes about 34 MJ of energy and emits 2.5 kg of CO₂ — more than 82% of steel grades. Typical recycled content is 35%.
Manufacturability8
36NiCrMo16 +QT-40's machinability is poor (30/100, worse than 89% of steel grades); weldability poor (20/100); formability poor (15/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 36NiCrMo16 +QT-40
Is 36NiCrMo16 easy to machine?
Machine in the +A condition (≈235 HB) where possible; in +QT at 40+ HRC use rigid setups, coated carbide or CBN, low speed and heavy positive feed to stay under the work-hardened layer.
Can 36NiCrMo16 be welded?
Poor weldability (CEV ≈ 1.2): avoid if possible, otherwise preheat 250–350 °C, low-hydrogen consumables, immediate post-weld temper below the part's tempering temperature.
Can 36NiCrMo16 be formed, bent or molded?
Hot forge 1100–850 °C then slow-cool/anneal to prevent air-hardening cracks; no meaningful cold forming in the hardened state — straighten warm or after tempering.
What surface finishes work on 36NiCrMo16?
Not anodizable; protect with phosphate + oil, Zn-Ni or Cd plating (bake 190 °C ≥ 8 h to de-embrittle), hard chrome or nitriding for wear surfaces; takes a fine polish for die and mould applications.
36NiCrMo16 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 – 0.39 | 0.36 |
| Si | ≤ 0.4 | 0.25 |
| Mn | 0.3 – 0.6 | 0.45 |
| P | ≤ 0.03 | 0.01 |
| S≤0.035 for base grade; ≤0.005 for +S-controlled / vacuum-degassed variants | ≤ 0.04 | 0.01 |
| Cr | 1.6 – 2 | 1.8 |
| Mo | 0.25 – 0.45 | 0.35 |
| Nisource of the very high hardenability | 3.6 – 4.1 | 3.85 |
| Fe | balance | — |
36NiCrMo16 +QT-40 — frequently asked
What is 36NiCrMo16 +QT-40 used for?
36NiCrMo16 +QT-40 is typically used for large forged shafts, heavy machinery components and high-strength structural forgings. In short: through-hardens thick sections; highest strength Ni-Cr-Mo grade; very poor weldability.
What is the yield strength of 36NiCrMo16 +QT-40?
36NiCrMo16 +QT-40 has a typical yield strength of 1,120 MPa (162 ksi) and a tensile strength of 1,330 MPa (193 ksi) — stronger than 93% of steel grades. Strength varies by condition: see the 9 listed tempers.
Is 36NiCrMo16 +QT-40 easy to machine?
Not especially — machinability is rated poor (30/100, worse than 89% of steel grades). Machine in the +A condition (≈235 HB) where possible; in +QT at 40+ HRC use rigid setups, coated carbide or CBN, low speed and heavy positive feed to stay under the work-hardened layer.
Can 36NiCrMo16 +QT-40 be welded?
Not readily — weldability is rated poor (20/100). Poor weldability (CEV ≈ 1.2): avoid if possible, otherwise preheat 250–350 °C, low-hydrogen consumables, immediate post-weld temper below the part's tempering temperature.
What surface finishes work on 36NiCrMo16 +QT-40?
Not anodizable; protect with phosphate + oil, Zn-Ni or Cd plating (bake 190 °C ≥ 8 h to de-embrittle), hard chrome or nitriding for wear surfaces; takes a fine polish for die and mould applications.
Can 36NiCrMo16 +QT-40 be formed, bent or molded?
Hot forge 1100–850 °C then slow-cool/anneal to prevent air-hardening cracks; no meaningful cold forming in the hardened state — straighten warm or after tempering.
What is the maximum service temperature of 36NiCrMo16 +QT-40?
36NiCrMo16 +QT-40 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.
What is the difference between 36NiCrMo16 +QT-40 and 36NiCrMo16 QT-1600?
+QT-40 is the default condition — standard stocked condition for bar and small forgings; the usual specification reference for this grade. QT-1600: choose for ultra-high-strength aerospace/landing-gear-type parts; toughness and hydrogen sensitivity become the design drivers. Yield strength is 1,120 MPa in +QT-40 versus 1,400 MPa in QT-1600.
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)
- EN 10027-2 / Werkstoff 1.6773 designation system — CEN (2015)
- 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)
- Ni-Cr-Mo through-hardening steel bar datasheets (1.6773 / 35NCD16 class) — European special steel producers (2023)
- GB/T 3077 (34CrNi3Mo comparable grade) — 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.