Steel E370
EN E370
Medium-carbon non-alloy steel specified by minimum yield strength (≥370 MPa) rather than chemistry, used as bar/rod stock for machine parts needing higher strength than mild steel but not full alloy hardening response.
Reference datasheet — E370 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the +AR condition
E370 tempers and conditions
E370 is supplied in 8 conditions, soft to hard. +AR is the default FabDigit quotes; the values on this page are for it.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Pick when maximum softness for cold forming, deep drilling or heavy cold heading is required before final heat treatment. | 310 | 560 | 20 | 165 HB | — |
Normalized | Choose for uniform fine-grained structure and better toughness/dimensional stability before machining or induction hardening. | 390 | 660 | 16 | 190 HB | — |
+ARDefault Hot rolled | Standard stock condition for E370 bar; pick when parts are fully machined from oversize black bar. | 400 | 720 | 10 | 210 HB | — |
Peeled / turned and straightened bar | Large-diameter alternative to cold drawn: hot-rolled properties with a clean, decarb-free turned surface and tight straightness. | 400 | 700 | 12 | 15 HRC | 9 % IACS |
Induction hardened | Use for wear surfaces on shafts and rails: hard case (~55 HRC) over a tough as-rolled or normalized core. | 400 | 720 | 8 | 55 HRC | 8.5 % IACS |
Cold drawn | Use for close-tolerance shafts and pins that need good surface finish and higher yield strength with minimal machining. | 620 | 800 | 7 | 22 HRC | — |
Quenched and tempered | Pick when higher strength with retained toughness is needed in small sections; hardenability is limited, so use ≤ ~40 mm diameter. | 620 | 850 | 14 | 25 HRC | — |
Quenched and tempered to a specified hardness band | Specify this band for gears, shafts and pins needing consistent strength and machinability after heat treatment. | 720 | 950 | 12 | 30 HRC | — |
What is E370?
Medium-carbon non-alloy steel specified by minimum yield strength (≥370 MPa) rather than chemistry, used as bar/rod stock for machine parts needing higher strength than mild steel but not full alloy hardening response. E370 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F). E370 has a yield strength of 400 MPa (58 ksi) and a tensile strength of 720 MPa (104 ksi) — weaker than 60% of steel grades. Elongation at break is 10% and the elastic modulus is 210 GPa (30.5 Msi).
What is E370 used for?
- machine shafts and pins
- levers and links
- fasteners requiring higher strength
- general mechanical components
Advantages
- Conducts heat well — 48 W/m·K (27.7 BTU/hr·ft·°F), better than 79% of steel grades
Limitations
- Limited ductility — 10%, worse than 91% of steel grades
- Low fracture toughness — 50 MPa·√m (45.5 ksi·√in), worse than 86% of steel grades
E370 properties
Typical room-temperature values for E370-+AR; bars are the position among steel grades.
Physical3
E370 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F).
Mechanical16
E370 has a yield strength of 400 MPa (58 ksi) and a tensile strength of 720 MPa (104 ksi) — weaker than 60% of steel grades. Elongation at break is 10% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
E370 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 11.8 µm/m·K (6.56 µin/in·°F).
Electrical3
E370 conducts electricity at 9 % IACS, better than 71% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (10/100), worse than 86% of steel grades.
Sustainability4
Producing a kilogram of E370 takes about 25 MJ of energy and emits 2.1 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 30%.
Manufacturability6
E370's machinability is fair (48/100, worse than 57% of steel grades); weldability poor (33/100); formability poor (30/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the steel family
Yield strength against density for every steel grade FabDigit runs. E370 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with E370
Is E370 easy to machine?
Machines like 1045: use carbide at 120–200 m/min with coolant; normalize or Q&T first to avoid gummy pearlite/ferrite banding and to improve surface finish.
Can E370 be welded?
Restricted weldability (CE ≈ 0.55–0.65) — preheat 150–250 °C, use low-hydrogen consumables and post-weld stress relief at 550–650 °C.
Can E370 be formed, bent or molded?
Hot forge at 1100–850 °C; cold bending is limited (generous bend radii, anneal first for severe forming).
E370 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 |
|---|---|---|
| Cnot fixed by the standard — grade is defined by mechanical properties; producers typically supply 0.40–0.50 %C | ≤ 0.55 | 0.45 |
| Sitypical producer analysis | ≤ 0.4 | 0.25 |
| Mntypical producer analysis | ≤ 1.1 | 0.75 |
| Pladle analysis limit for non-alloy engineering steels | ≤ 0.05 | 0.03 |
| Sladle analysis limit | ≤ 0.05 | 0.03 |
| Nladle analysis limit unless N-binding elements present | ≤ 0.01 | 0.01 |
| Fe | balance |
What surface finishes work on E370?
Not anodizable — protect with paint, phosphate + oil, zinc plating, blackening or hard chrome; surfaces can be induction hardened and ground.
Surface treatments FabDigit runs on steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Organic Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Steel E370 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- EN / DIN / Werkstoff-Nr.
- 1.0261
How much does E370 cost?
E370 is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
E370 — frequently asked
What is E370 used for?
E370 is typically used for machine shafts and pins, levers and links, fasteners requiring higher strength and general mechanical components. In short: strength-classified carbon bar; stronger than mild steel; limited weldability, restricted forming.
What is the yield strength of E370?
E370 has a typical yield strength of 400 MPa (58 ksi) and a tensile strength of 720 MPa (104 ksi) — weaker than 60% of steel grades. Strength varies by condition: see the 8 listed tempers.
Is E370 easy to machine?
Reasonably — machinability is rated fair (48/100, worse than 57% of steel grades). Machines like 1045: use carbide at 120–200 m/min with coolant; normalize or Q&T first to avoid gummy pearlite/ferrite banding and to improve surface finish.
Can E370 be welded?
Not readily — weldability is rated poor (33/100). Restricted weldability (CE ≈ 0.55–0.65) — preheat 150–250 °C, use low-hydrogen consumables and post-weld stress relief at 550–650 °C.
What surface finishes work on E370?
Not anodizable — protect with paint, phosphate + oil, zinc plating, blackening or hard chrome; surfaces can be induction hardened and ground.
Can E370 be formed, bent or molded?
Hot forge at 1100–850 °C; cold bending is limited (generous bend radii, anneal first for severe forming).
What is the maximum service temperature of E370?
E370 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 E370 +AR and E370-IH?
+AR is the default condition — standard stock condition for E370 bar; pick when parts are fully machined from oversize black bar. IH: use for wear surfaces on shafts and rails: hard case (~55 HRC) over a tough as-rolled or normalized core. Yield strength is 400 MPa in +AR versus 400 MPa in IH.
How much does E370 cost?
E370 is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- EN 10025-2 (non-alloy structural/engineering steels, E-series analogues E295/E335/E360) — CEN (2019)
- EN 10277 — Bright steel products, technical delivery conditions — CEN (2018)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- GB/T 699 (45 comparison grade) — SAC (2015)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.