Steel C45E · heat-treated state
Steel C45E IH 55 HRC
Properties of the IH 55 HRC condition, compared with the other C45E tempers.
Pick when a hard, wear-resistant running surface is needed on a tough core (shaft journals, guide rails, gear teeth).
What is C45E IH 55 HRC?
C45E IH 55 HRC is C45E heat treated to IH 55 HRC — pick when a hard, wear-resistant running surface is needed on a tough core (shaft journals, guide rails, gear teeth). C45E IH 55 HRC has a yield strength of 520 MPa (75.4 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 67% of steel grades. Elongation at break is 14% and the elastic modulus is 210 GPa (30.5 Msi). C45E IH 55 HRC 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). Normalized is the default condition FabDigit quotes; IH 55 HRC is available on request or by drawing note.
Advantages
- High electrical conductivity — 10 % IACS, better than 82% of steel grades
- Conducts heat well — 48 W/m·K (27.7 BTU/hr·ft·°F), better than 79% of steel grades
Limitations
- Difficult to machine — 12/100, worse than 99% of steel grades
- Difficult to weld — 10/100, worse than 99% of steel grades
- Limited service temperature — 180°C (356 °F), worse than 98% of steel grades
- Low fracture toughness — 50 MPa·√m (45.5 ksi·√in), worse than 87% of steel grades
- Limited ductility — 14%, worse than 75% of steel grades
C45E IH 55 HRC properties
Typical room-temperature values for C45E IH 55 HRC — 9 properties are specific to this condition; the rest are grade-level values shared by every C45E temper. Each bar shows where the value sits among the steel grades in FabDigit's library — further right is higher.
Physical3
C45E IH 55 HRC 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
C45E IH 55 HRC has a yield strength of 520 MPa (75.4 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 67% of steel grades. Elongation at break is 14% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
C45E IH 55 HRC is rated for continuous service to 180°C (356 °F). It conducts heat at 48 W/m·K (27.7 BTU/hr·ft·°F), better than 79% of steel grades. Thermal expansion is 11.5 µm/m·K (6.39 µin/in·°F).
Electrical3
C45E IH 55 HRC conducts electricity at 10 % IACS, better than 82% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (10/100), worse than 87% of steel grades.
Sustainability4
Producing a kilogram of C45E IH 55 HRC takes about 24 MJ of energy and emits 2 kg of CO₂ — less than 97% of steel grades. Typical recycled content is 30%.
Manufacturability7
C45E IH 55 HRC's machinability is not recommended (12/100, worse than 99% of steel grades); weldability not recommended (10/100); formability fair (40/100).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other C45E tempers and conditions
C45E is also supplied in 6 other conditions. The full side-by-side table is on the C45E overview.
- NormalizedDefaultStandard stock condition: uniform fine pearlitic structure, balanced strength and machinability.380 MPa yield · 190 HB
- Q&T 28-32 HRCHigher-strength through-hardened condition for loaded shafts and gear blanks in thin/medium sections.750 MPa yield · 30 HRC
- Cold DrawnBright, close-tolerance bar with raised yield strength for shafts and turned parts made without further heat treatment.560 MPa yield · 215 HB
- QTGeneral-purpose tough/strong condition for shafts, gears and fasteners; use for sections up to roughly 40 mm.520 MPa yield · 21 HRC
- IH 55 HRCPick when a hard, wear-resistant running surface is needed on a tough core (shaft journals, guide rails, gear teeth).520 MPa yield · 56 HRC
- AnnealedSoftest condition for deep machining, cold forming or before hardening.320 MPa yield · 170 HB
Working with C45E IH 55 HRC
Is C45E easy to machine?
Machines well in +N or +C at ~120–180 m/min with carbide; annealed material can smear, and above ~30 HRC use coated carbide/CBN and rigid setups.
Can C45E be welded?
CE ≈ 0.55 — preheat 150–250 °C, use low-hydrogen consumables, control interpass and stress-relieve/re-temper afterwards to avoid martensitic cracking.
Can C45E be formed, bent or molded?
Hot forge at 1100–850 °C then normalize; cold bending is limited (recommend bend radius ≥ 3t and annealed material).
What surface finishes work on C45E?
No anodizing; protect with oil, phosphate, black oxide, zinc or hard-chrome plating, nitriding for wear, and paint for outdoor service.
C45E 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 | 0.42 – 0.5 | 0.45 |
| Si | ≤ 0.4 | 0.25 |
| Mn | 0.5 – 0.8 | 0.65 |
| P | ≤ 0.03 | — |
| SE grade: controlled max sulphur | ≤ 0.04 | — |
| Cr | ≤ 0.4 | — |
| Mo | ≤ 0.1 | — |
| NiCr+Mo+Ni ≤ 0.63 | ≤ 0.4 | — |
| Fe | balance | — |
C45E IH 55 HRC — frequently asked
What is C45E IH 55 HRC used for?
C45E IH 55 HRC is typically used for crankshafts, shafts and industrial bolts. In short: european medium-carbon bar.
What is the yield strength of C45E IH 55 HRC?
C45E IH 55 HRC has a typical yield strength of 520 MPa (75.4 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 67% of steel grades. Strength varies by condition: see the 7 listed tempers.
Is C45E IH 55 HRC easy to machine?
Not especially — machinability is rated not recommended (12/100, worse than 99% of steel grades). Machines well in +N or +C at ~120–180 m/min with carbide; annealed material can smear, and above ~30 HRC use coated carbide/CBN and rigid setups.
Can C45E IH 55 HRC be welded?
Not readily — weldability is rated not recommended (10/100). CE ≈ 0.55 — preheat 150–250 °C, use low-hydrogen consumables, control interpass and stress-relieve/re-temper afterwards to avoid martensitic cracking.
What surface finishes work on C45E IH 55 HRC?
No anodizing; protect with oil, phosphate, black oxide, zinc or hard-chrome plating, nitriding for wear, and paint for outdoor service.
Can C45E IH 55 HRC be formed, bent or molded?
Hot forge at 1100–850 °C then normalize; cold bending is limited (recommend bend radius ≥ 3t and annealed material).
What is the maximum service temperature of C45E IH 55 HRC?
C45E IH 55 HRC is rated for continuous use to about 180°C (356 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between C45E Normalized and C45E-QT?
Normalized is the default condition — standard stock condition: uniform fine pearlitic structure, balanced strength and machinability. QT: general-purpose tough/strong condition for shafts, gears and fasteners; use for sections up to roughly 40 mm. Yield strength is 380 MPa in Normalized versus 520 MPa in QT.
Can FabDigit make parts in C45E IH 55 HRC?
Yes — C45E IH 55 HRC is available for CNC machining and sheet metal with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- EN 10083-2 Steels for quenching and tempering — Non-alloy steels — CEN (2006)
- EN 10277 Bright steel products — technical delivery conditions — CEN (2018)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels — ASM International (1990)
- ASM Handbook Vol.16 — Machining; Vol.19 — Fatigue and Fracture — ASM International (1996)
- 1.1191 / C45E datasheet — Böhler / Deutsche Edelstahlwerke (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.