Steel 50CrMo4-IH (Induction hardened)
Heat-treated state
EN 50CrMo4
Best choice for journals, spline flanks and hydraulic rods needing surface wear plus tough core.
Values for the IH condition
Other 50CrMo4 tempers and conditions
50CrMo4 is listed in 13 conditions; see the grade overview at 50CrMo4.
Compare all 13 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Choose for machining, deep drilling or cold sawing before final hardening. | 440 | 760 | 18 | 230 HB | — |
Hot rolled | Cheapest stock form, bought for forging or full re-heat-treatment by the user. | 500 | 850 | 14 | 25 HRC | 8.2 % IACS |
Normalized | Uniform pearlitic structure for forging stock or before final quench-and-temper. | 550 | 900 | 15 | 27 HRC | — |
+QT | Large-diameter forged shafts and rolls where only partial hardening depth is possible. | 570 | 870 | 14 | 26 HRC | 7.8 % IACS |
+QT | Medium shafts and forgings; strength reduced by mass effect. | 700 | 1,000 | 12 | 31 HRC | 7.8 % IACS |
Cold drawn | Close-tolerance bright bar for parts finished without further heat treatment. | 700 | 880 | 10 | 26 HRC | 8.2 % IACS |
Q&T to 28–32 HRC | Pick when impact toughness and machinability matter more than wear. | 830 | 980 | 15 | 30 HRC | — |
+QTDefault Quenched and tempered | Standard stocked condition: oil/polymer quench from ~840 °C, temper 540–680 °C for balanced strength and toughness. | 850 | 1,100 | 11 | 34 HRC | — |
IHThis page Induction hardened | Best choice for journals, spline flanks and hydraulic rods needing surface wear plus tough core. | 850 | 1,100 | 10 | 58 HRC | 7.5 % IACS |
+QT | Thin bars/pins where full martensitic hardening through-section is achieved. | 950 | 1,200 | 10 | 38 HRC | 7.8 % IACS |
Q&T to 34–38 HRC | Common pre-hardened supply for shafts, spindles and holder bodies machined to finish size. | 1,000 | 1,150 | 12 | 36 HRC | — |
Q&T to 40–45 HRC | For collets, chucks, wear plates and tool bodies needing hardness with some toughness. | 1,220 | 1,380 | 10 | 43 HRC | — |
Hardened + low temper (180–250 °C), 50–55 HRC | Maximum hardness/wear condition for dies, guides and cams; low toughness, grind-finish only. | 1,500 | 1,800 | 5 | 53 HRC | — |
What is 50CrMo4-IH?
50CrMo4-IH is 50CrMo4 heat treated to IH — best choice for journals, spline flanks and hydraulic rods needing surface wear plus tough core. 50CrMo4-IH has a yield strength of 850 MPa (123 ksi) and a tensile strength of 1,100 MPa (160 ksi) — stronger than 88% of steel grades. Elongation at break is 10% and the elastic modulus is 210 GPa (30.5 Msi). 50CrMo4-IH 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; IH is available on request or by drawing note.
Advantages
- High strength — 850 MPa (123 ksi), better than 88% of steel grades
- Polishes to a fine finish — 65/100, better than 78% of steel grades
Limitations
- Difficult to machine — 12/100, worse than 99% of steel grades
- Difficult to weld — 8/100, worse than 99% of steel grades
- Limited formability — 3/100, worse than 99% of steel grades
- Low fracture toughness — 30 MPa·√m (27.3 ksi·√in), worse than 96% of steel grades
- Limited service temperature — 200°C (392 °F), worse than 93% of steel grades
50CrMo4-IH properties
Typical room-temperature values for 50CrMo4-IH; 22 are specific to this condition. Other listed values are 50CrMo4 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
50CrMo4-IH 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
50CrMo4-IH has a yield strength of 850 MPa (123 ksi) and a tensile strength of 1,100 MPa (160 ksi) — stronger than 88% of steel grades. Elongation at break is 10% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
50CrMo4-IH is rated for continuous service to 200°C (392 °F). It conducts heat at 41 W/m·K (23.7 BTU/hr·ft·°F), worse than 62% of steel grades. Thermal expansion is 11.2 µm/m·K (6.22 µin/in·°F).
Electrical3
50CrMo4-IH conducts electricity at 7.5 % IACS, worse than 67% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (11/100), worse than 73% of steel grades.
Sustainability4
Producing a kilogram of 50CrMo4-IH takes about 29 MJ of energy and emits 2.1 kg of CO₂ — less than 53% of steel grades. Typical recycled content is 30%.
Manufacturability8
50CrMo4-IH's machinability is not recommended (12/100, worse than 99% of steel grades); weldability not recommended (8/100); formability not recommended (3/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 50CrMo4-IH
Is 50CrMo4 easy to machine?
Machine in +A or ≤32 HRC condition with coated carbide (Vc ≈ 120–180 m/min annealed, 60–100 m/min at 34 HRC); above 45 HRC switch to CBN hard turning or grinding.
Can 50CrMo4 be welded?
Poor weldability (CE ≈ 0.9): preheat 250–350 °C, low-hydrogen consumables, interpass control and immediate 600–660 °C PWHT; avoid welding in the hardened condition.
Can 50CrMo4 be formed, bent or molded?
Hot form/forge 1100→850 °C with slow cooling in furnace or ash; cold bending or heading is not practical — use annealed stock and small strains only.
What surface finishes work on 50CrMo4?
Not anodizable; protect with black oxide, manganese phosphate, zinc or hard chrome plating, or gas nitride (Q&T ≥ tempering above 550 °C) — bake at 190–220 °C after plating to avoid hydrogen embrittlement.
50CrMo4 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 |
|---|---|---|
| CEN 10083-3 | 0.46 – 0.54 | 0.5 |
| Si | ≤ 0.4 | 0.25 |
| Mn | 0.5 – 0.8 | 0.65 |
| P | ≤ 0.03 | 0.02 |
| S≤0.035 standard; ≤0.005 for quality class +S grades | ≤ 0.04 | 0.02 |
| Cr | 0.9 – 1.2 | 1.05 |
| Mo | 0.15 – 0.3 | 0.22 |
| Fe | balance | — |
50CrMo4-IH — frequently asked
What is 50CrMo4-IH used for?
50CrMo4-IH is typically used for high-strength bolts, springs, gears, molds and structural shafts. In short: higher-carbon 42CrMo4 upgrade; through-hardens above 40 HRC; poor weldability by design.
What is the yield strength of 50CrMo4-IH?
50CrMo4-IH has a typical yield strength of 850 MPa (123 ksi) and a tensile strength of 1,100 MPa (160 ksi) — stronger than 88% of steel grades. Strength varies by condition: see the 13 listed tempers.
Is 50CrMo4-IH easy to machine?
Not especially — machinability is rated not recommended (12/100, worse than 99% of steel grades). Machine in +A or ≤32 HRC condition with coated carbide (Vc ≈ 120–180 m/min annealed, 60–100 m/min at 34 HRC); above 45 HRC switch to CBN hard turning or grinding.
Can 50CrMo4-IH be welded?
Not readily — weldability is rated not recommended (8/100). Poor weldability (CE ≈ 0.9): preheat 250–350 °C, low-hydrogen consumables, interpass control and immediate 600–660 °C PWHT; avoid welding in the hardened condition.
What surface finishes work on 50CrMo4-IH?
Not anodizable; protect with black oxide, manganese phosphate, zinc or hard chrome plating, or gas nitride (Q&T ≥ tempering above 550 °C) — bake at 190–220 °C after plating to avoid hydrogen embrittlement.
Can 50CrMo4-IH be formed, bent or molded?
Hot form/forge 1100→850 °C with slow cooling in furnace or ash; cold bending or heading is not practical — use annealed stock and small strains only.
What is the maximum service temperature of 50CrMo4-IH?
50CrMo4-IH is rated for continuous use to about 200°C (392 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 50CrMo4 +QT and 50CrMo4-IH?
+QT is the default condition — standard stocked condition: oil/polymer quench from ~840 °C, temper 540–680 °C for balanced strength and toughness. IH: best choice for journals, spline flanks and hydraulic rods needing surface wear plus tough core. Yield strength is 850 MPa in +QT versus 850 MPa in IH.
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)
- GB/T 3077 (50CrMo equivalent) — SAC (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)
- Cr-Mo quenched and tempered steel 1.7228 datasheet — European special steel producers (Böhler / Deutsche Edelstahlwerke class data) (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.