BS970 EN8 CARBON STEEL | 080M40
EN8 Carbon steel is a medium carbon steel with 0.36-0.44% C as per BS 970 standard. It has moderate tensile strength between 500-800Mpa.It is generally supplied in untreated condition or in the normalized condition.EN8 can be hardened by quenching and tempering on limited sections,and also can be flame or induction hardened to produce a good surface hardness(50-55HRC) with moderate wear resistance.
EN8 steel can be easily machined in any condition,and can be welded using suitable welding techniques with the correct procedure.
1.EN8 steel Supply Form & Size
Hot rolled round bar:Φ20-Φ200mm,Length:3000-6000mm
Hot Forged round bar:Φ80-Φ1000mm,Length:3000-10000mm
Flat bar/Blcoks:Thickness :120-800mm xWidth:120-1500mm,Length:2000-6000mm
2.Surface Finish&Tolerance
| Surface Finish | Black-Forged | Black-Rolled | Turned | Grinding | Polished | Peeled | Cold Drawn |
| Tolerance | (0，+5mm) | (0，+1mm) | (0，+3mm) | Best h9 | Best h11 | Best H11 | Best H11 |
3.EN8 Steel Chemical Composition
| Grade | C | Si | Mn | P | S |
| EN8/080M40 | 0.36-0.44 | 0.1-0.4 | 0.60-1.0 | ≤ 0.05 | ≤ 0.05 |
| EN8D/080A42 | 0.4-0.45 | 0.1-0.4 | 0.7-0.9 | ≤ 0.05 | ≤ 0.05 |
| EN8M/212A42 | 0.4-0.45 | ≤ 0.25 | 1.0-1.3 | ≤ 0.06 | 0.12-0.2 |
4.EN8 Steel Related Specifications
- BS 970-1991:080M40
- AISI/ASTM A29:1038, 1039,1040,1042,1043, 1045
- DIN Werkstoff No.: 1.0511, 1.1186, 1.1189
- BS & DIN European: C40, CK40, C45, CK45
- JIS G4051: S40C, S45C
5.Mechanical Property For EN8 Steel
| Condition | N | Q | R |
| Ruling Section,mm | 254 | 65 | 20 |
| Tensile Strength,Mpa | 510-540 | 620-770 | 690-850 |
| Yield Strength,Mpa | ≥ 245 | ≥385 | ≥465 |
| Elongation | 17% | 16% | 16% |
| ISO V Impact,J | 20 | 33 | 33 |
| Hardness,HBW | 152-207 | 179-229 | 201-255 |
6.EN8 steel Forging
Forging temperature:950-1050℃,EN8 steel should be cooled as slowly as possible in still air or in sand after forged.
6.Heat Treatment For EN8 Steel
- Normalizing
The normalizing temperature range for this grade is typically 830-860ºC,followed by cooling in still air.
- Annealing
Heat slowly to 680-710°C, soak well. Cool slowly in the furnace.
- Hardening
Hardening of this grade is carried out from an austenitizing temperature of 820-860ºC followed by oil or water quenching.
- Tempering
Carbon steel EN8 or 080m40 can be tempered at a heat of between 550°C to 660°C,heating for about 1 hour for every inch of thickness, then cool in oil or water.
7.EN8 Steel Application
EN8 is a popular steel in industry from the automotive trade to wider general engineering applications,it is widely used for many general engineering applications.
- Automotive parts
- Connecting rods
- Studs, bolts
- Axles, spindles
- General engineering components