Steel 33NiCrMoV14-5 +QT+Nitr (+QT + gas nitrided)
Finish state
EN 33NiCrMoV14-5
Pick when journal/spline wear and fatigue at the surface matter; V and Cr give a hard, stable nitrided case.
Values for the +QT+Nitr condition
Other 33NiCrMoV14-5 tempers and conditions
33NiCrMoV14-5 is listed in 6 conditions; see the grade overview at 33NiCrMoV14-5.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Machining/rough-turning condition before final quench and temper. | 550 | 850 | 18 | 24 HRC | 6 % IACS |
Normalized and tempered | Intermediate condition for very large forgings or as pre-treatment before final Q&T. | 700 | 950 | 16 | 30 HRC | 5.7 % IACS |
Quenched and tempered, Rm 900–1100 MPa | High-tempering condition for large turbine/generator shafts where toughness and low-temperature notch behaviour dominate. | 800 | 980 | 16 | 31 HRC | — |
+QT+NitrThis page +QT + gas nitrided | Pick when journal/spline wear and fatigue at the surface matter; V and Cr give a hard, stable nitrided case. | 1,030 | 1,250 | 11 | 62 HRC | 5.7 % IACS |
+QTDefault Quenched and tempered | Standard commercial condition: best balance of ~1000 MPa yield with usable impact toughness in thick forgings. | 1,050 | 1,250 | 12 | 40 HRC | — |
Quenched and low-tempered, Rm 1450–1650 MPa | Maximum-strength condition for small highly loaded shafts and gears; toughness and SCC/hydrogen resistance drop sharply. | 1,350 | 1,550 | 10 | 46 HRC | — |
What is 33NiCrMoV14-5 +QT+Nitr?
33NiCrMoV14-5 +QT+Nitr is 33NiCrMoV14-5 supplied in the +QT+Nitr condition — pick when journal/spline wear and fatigue at the surface matter; V and Cr give a hard, stable nitrided case. 33NiCrMoV14-5 +QT+Nitr has a yield strength of 1,030 MPa (149 ksi) and a tensile strength of 1,250 MPa (181 ksi) — stronger than 93% of steel grades. Elongation at break is 11% and the elastic modulus is 207 GPa (30 Msi). 33NiCrMoV14-5 +QT+Nitr 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). +QT is the default condition FabDigit quotes; +QT+Nitr is available on request or by drawing note.
Advantages
- High strength — 1,030 MPa (149 ksi), better than 93% of steel grades
- Polishes to a fine finish — 70/100, better than 87% of steel grades
- High service temperature — 450°C (842 °F), better than 86% of steel grades
Limitations
- Difficult to weld — 5/100, worse than 100% of steel grades
- Difficult to machine — 10/100, worse than 99% of steel grades
- Limited formability — 3/100, worse than 99% of steel grades
- Limited ductility — 11%, worse than 89% of steel grades
- Poor heat conductor — 32 W/m·K (18.5 BTU/hr·ft·°F), worse than 82% of steel grades
33NiCrMoV14-5 +QT+Nitr properties
Typical room-temperature values for 33NiCrMoV14-5 +QT+Nitr; 21 are specific to this condition. Other listed values are 33NiCrMoV14-5 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
33NiCrMoV14-5 +QT+Nitr 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
33NiCrMoV14-5 +QT+Nitr has a yield strength of 1,030 MPa (149 ksi) and a tensile strength of 1,250 MPa (181 ksi) — stronger than 93% of steel grades. Elongation at break is 11% and the elastic modulus is 207 GPa (30 Msi).
Thermal6
33NiCrMoV14-5 +QT+Nitr is rated for continuous service to 450°C (842 °F). It conducts heat at 32 W/m·K (18.5 BTU/hr·ft·°F), worse than 82% of steel grades. Thermal expansion is 11.5 µm/m·K (6.39 µin/in·°F).
Electrical2
33NiCrMoV14-5 +QT+Nitr has an electrical resistivity of 3×10⁻⁷ Ω·m.
Chemical & Environmental2
Corrosion resistance is poor (20/100), better than 87% of steel grades.
Sustainability4
Producing a kilogram of 33NiCrMoV14-5 +QT+Nitr takes about 34 MJ of energy and emits 2.5 kg of CO₂ — more than 82% of steel grades. Typical recycled content is 30%.
Manufacturability7
33NiCrMoV14-5 +QT+Nitr's machinability is not recommended (10/100, worse than 99% of steel grades); weldability not recommended (5/100); formability not recommended (3/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 33NiCrMoV14-5 +QT+Nitr
Is 33NiCrMoV14-5 easy to machine?
Rough machine in the annealed/normalized state; in +QT (≈40 HRC) use rigid setups, coated carbide or CBN at reduced speed and heavy coolant, and finish-grind bearing surfaces.
Can 33NiCrMoV14-5 be welded?
Poor weldability due to high carbon equivalent — preheat 250–350 °C, low-hydrogen matching or slightly softer filler, and immediate post-weld temper below the last tempering temperature.
Can 33NiCrMoV14-5 be formed, bent or molded?
Hot forge 1050–1150 °C with slow controlled cooling to avoid quench cracks; no practical cold forming, straightening only warm.
What surface finishes work on 33NiCrMoV14-5?
Not corrosion resistant: use phosphating, oil, paint, Zn/Ni or hard-chrome plating; gas nitriding gives an excellent wear/fatigue surface, and the fine tempered martensite polishes well.
33NiCrMoV14-5 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 | 0.3 – 0.36 | 0.33 |
| Si | ≤ 0.4 | 0.25 |
| Mn | 0.3 – 0.6 | 0.45 |
| Pmax; rotor forgings often ≤0.010 | ≤ 0.02 | 0.01 |
| Smax; low-S practice for toughness | ≤ 0.02 | 0.01 |
| Cr | 1.1 – 1.4 | 1.25 |
| Mo | 0.3 – 0.5 | 0.4 |
| Ni | 3.3 – 3.8 | 3.5 |
| V | 0.08 – 0.15 | 0.1 |
| Fe | balance | — |
33NiCrMoV14-5 +QT+Nitr — frequently asked
What is 33NiCrMoV14-5 +QT+Nitr used for?
33NiCrMoV14-5 +QT+Nitr is typically used for turbine shafts, generator rotors and heavy forged components. In short: 1250 MPa forging grade; deep-hardening rotor steel; nitrides for wear surfaces.
What is the yield strength of 33NiCrMoV14-5 +QT+Nitr?
33NiCrMoV14-5 +QT+Nitr has a typical yield strength of 1,030 MPa (149 ksi) and a tensile strength of 1,250 MPa (181 ksi) — stronger than 93% of steel grades. Strength varies by condition: see the 6 listed tempers.
Is 33NiCrMoV14-5 +QT+Nitr easy to machine?
Not especially — machinability is rated not recommended (10/100, worse than 99% of steel grades). Rough machine in the annealed/normalized state; in +QT (≈40 HRC) use rigid setups, coated carbide or CBN at reduced speed and heavy coolant, and finish-grind bearing surfaces.
Can 33NiCrMoV14-5 +QT+Nitr be welded?
Not readily — weldability is rated not recommended (5/100). Poor weldability due to high carbon equivalent — preheat 250–350 °C, low-hydrogen matching or slightly softer filler, and immediate post-weld temper below the last tempering temperature.
What surface finishes work on 33NiCrMoV14-5 +QT+Nitr?
Not corrosion resistant: use phosphating, oil, paint, Zn/Ni or hard-chrome plating; gas nitriding gives an excellent wear/fatigue surface, and the fine tempered martensite polishes well.
Can 33NiCrMoV14-5 +QT+Nitr be formed, bent or molded?
Hot forge 1050–1150 °C with slow controlled cooling to avoid quench cracks; no practical cold forming, straightening only warm.
What is the maximum service temperature of 33NiCrMoV14-5 +QT+Nitr?
33NiCrMoV14-5 +QT+Nitr is rated for continuous use to about 450°C (842 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- EN 10250-3 Open die steel forgings for general engineering purposes — Alloy special steels — CEN (2000)
- SEW 555 / Stahl-Eisen-Werkstoffblatt for Ni-Cr-Mo-V forging steels — Verlag Stahleisen (1998)
- ASM Handbook Vol.1: Properties and Selection — Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.19: Fatigue and Fracture (rotor and shaft steels) — ASM International (1996)
- ISO 18265 Metallic materials — Conversion of hardness values — ISO (2013)
- Heavy forging / rotor shaft steel datasheets (1.6956 class) — European special-steel forging producers (2022)
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.