Steel EN353 · supply condition · default condition
Steel EN353-HR
Properties of the HR condition, compared with the other EN353 tempers.
Standard stocked condition for gear blanks and forging stock; machined then carburized.
What is EN353-HR?
EN353-HR is EN353 supplied in the HR condition — standard stocked condition for gear blanks and forging stock; machined then carburized. EN353-HR has a yield strength of 480 MPa (69.6 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 60% of steel grades. Elongation at break is 18% and the elastic modulus is 210 GPa (30.5 Msi). EN353-HR 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).
Limitations
- Limited service temperature — 200°C (392 °F), worse than 93% of steel grades
EN353-HR properties
Typical room-temperature values for EN353-HR — 9 properties are specific to this condition; the rest are grade-level values shared by every EN353 temper. Each bar shows where the value sits among the steel grades in FabDigit's library — further right is higher.
Physical3
EN353-HR 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
EN353-HR has a yield strength of 480 MPa (69.6 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 60% of steel grades. Elongation at break is 18% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
EN353-HR is rated for continuous service to 200°C (392 °F). It conducts heat at 44 W/m·K (25.4 BTU/hr·ft·°F), better than 57% of steel grades. Thermal expansion is 11.8 µm/m·K (6.56 µin/in·°F).
Electrical3
EN353-HR conducts electricity at 7.8 % IACS, worse than 58% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of EN353-HR takes about 30 MJ of energy and emits 2.1 kg of CO₂ — more than 55% of steel grades. Typical recycled content is 25%.
Manufacturability7
EN353-HR's machinability is good (55/100, better than 62% of steel grades); weldability fair (40/100); formability fair (45/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other EN353 tempers and conditions
EN353 is also supplied in 6 other conditions. The full side-by-side table is on the EN353 overview.
- HRDefaultStandard stocked condition for gear blanks and forging stock; machined then carburized.480 MPa yield · 229 HB
- CHThe service condition for gears and pinions — hard wear-resistant case on a tough 30–42 HRC core.900 MPa yield · 60 HRC
- Q&TDirect hardening without carburizing when a tough, uniformly strong shaft or fastener core is wanted.800 MPa yield · 32 HRC
- CDChoose for close size tolerance, bright finish and higher as-supplied strength on small-diameter bar.660 MPa yield · 250 HB
- NormalizedUse to refine grain and homogenize forgings before carburizing; uniform machining response.550 MPa yield · 240 HB
- AnnealedPick for deep machining, broaching, hobbing or cold forming before carburizing.400 MPa yield · 190 HB
Working with EN353-HR
Is EN353 easy to machine?
Machine fully in the annealed or normalized state with carbide tooling (~120–180 m/min); after carburizing only grinding, honing or CBN hard-turning is practical.
Can EN353 be welded?
Weldable only before carburizing — preheat 200–250 °C, low-hydrogen consumables, post-weld stress relief; welding a carburized case will crack it.
Can EN353 be formed, bent or molded?
Hot forge at 1100–1150 °C and normalize afterwards; cold forming is limited to gentle bends in the annealed condition.
What surface finishes work on EN353?
No natural corrosion resistance — protect with oil, phosphate, black oxide, zinc/manganese phosphate or plating; keep 0.1–0.3 mm grinding stock for post-carburizing distortion.
EN353 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 |
|---|---|---|
| Ccase-hardening carbon level | 0.14 – 0.2 | 0.17 |
| Si | 0.15 – 0.35 | 0.25 |
| Mn | 0.6 – 0.9 | 0.75 |
| P | ≤ 0.04 | — |
| S | ≤ 0.04 | — |
| Cr | 0.75 – 1.25 | 1 |
| Ni | 1 – 1.5 | 1.25 |
| Mo | 0.08 – 0.15 | 0.12 |
| Fe | balance | — |
EN353-HR — frequently asked
What is EN353-HR used for?
EN353-HR is typically used for gears, industrial drive shafts and pins. In short: premium carburizing alloy bar.
What is the yield strength of EN353-HR?
EN353-HR has a typical yield strength of 480 MPa (69.6 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 60% of steel grades. Strength varies by condition: see the 7 listed tempers.
Is EN353-HR easy to machine?
Reasonably — machinability is rated good (55/100, better than 62% of steel grades). Machine fully in the annealed or normalized state with carbide tooling (~120–180 m/min); after carburizing only grinding, honing or CBN hard-turning is practical.
Can EN353-HR be welded?
With care — weldability is rated fair (40/100). Weldable only before carburizing — preheat 200–250 °C, low-hydrogen consumables, post-weld stress relief; welding a carburized case will crack it.
What surface finishes work on EN353-HR?
No natural corrosion resistance — protect with oil, phosphate, black oxide, zinc/manganese phosphate or plating; keep 0.1–0.3 mm grinding stock for post-carburizing distortion.
Can EN353-HR be formed, bent or molded?
Hot forge at 1100–1150 °C and normalize afterwards; cold forming is limited to gentle bends in the annealed condition.
What is the maximum service temperature of EN353-HR?
EN353-HR 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 EN353-HR and EN353-CH?
HR is the default condition — standard stocked condition for gear blanks and forging stock; machined then carburized. CH: the service condition for gears and pinions — hard wear-resistant case on a tough 30–42 HRC core. Yield strength is 480 MPa in HR versus 900 MPa in CH.
Can FabDigit make parts in EN353-HR?
Yes — EN353-HR 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
- BS 970-3: Wrought steels — 815M17 case hardening steel — BSI (1991)
- GB/T 3077 (20CrNi2Mo) — SAC (2015)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels — ASM International (1990)
- ASM Handbook Vol.4 — Heat Treating (Carburizing) — ASM International (1991)
- Alloy carburizing bar steel datasheets (EN353 / 815M17 / 20CrNi2Mo) — Various bar producers (2023)
- SMM / Mysteel — SMM / Mysteel (2026)
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.