Steel C45E · temper
Steel C45E Annealed
Properties of the Annealed condition, compared with the other C45E tempers.
Softest condition for deep machining, cold forming or before hardening.
What is C45E Annealed?
C45E Annealed is C45E in the Annealed temper — softest condition for deep machining, cold forming or before hardening. C45E Annealed has a yield strength of 320 MPa (46.4 ksi) and a tensile strength of 580 MPa (84.1 ksi) — weaker than 80% of steel grades. Elongation at break is 20% and the elastic modulus is 210 GPa (30.5 Msi). C45E Annealed 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; Annealed 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
- Low fracture toughness — 50 MPa·√m (45.5 ksi·√in), worse than 87% of steel grades
- Low strength — 320 MPa (46.4 ksi), worse than 80% of steel grades
C45E Annealed properties
Typical room-temperature values for C45E Annealed — 12 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 Annealed 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 Annealed has a yield strength of 320 MPa (46.4 ksi) and a tensile strength of 580 MPa (84.1 ksi) — weaker than 80% of steel grades. Elongation at break is 20% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
C45E Annealed is rated for continuous service to 350°C (662 °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 Annealed 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 Annealed 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 Annealed's machinability is good (58/100, better than 75% of steel grades); weldability fair (50/100); formability good (55/100).
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 Annealed
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 Annealed — frequently asked
What is C45E Annealed used for?
C45E Annealed is typically used for crankshafts, shafts and industrial bolts. In short: european medium-carbon bar.
What is the yield strength of C45E Annealed?
C45E Annealed has a typical yield strength of 320 MPa (46.4 ksi) and a tensile strength of 580 MPa (84.1 ksi) — weaker than 80% of steel grades. Strength varies by condition: see the 7 listed tempers.
Is C45E Annealed easy to machine?
Reasonably — machinability is rated good (58/100, better than 75% 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 Annealed be welded?
With care — weldability is rated fair (50/100). 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 Annealed?
No anodizing; protect with oil, phosphate, black oxide, zinc or hard-chrome plating, nitriding for wear, and paint for outdoor service.
Can C45E Annealed 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 Annealed?
C45E Annealed 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 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 Annealed?
Yes — C45E Annealed 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.