Product Description
EN8 is usually supplied untreated but can be supplied to order in the normalized or finally heat treated (quenched and tempered to “Q” or “R”properties for limiting ruling sections up to 63mm), which is adequate for a wide range of applications.
EN8 is a very popular grade of through-hardening medium carbon steel, which is readily machinable in any condition. EN8 is suitable for the manufacture of parts such as general-purpose axles and shafts, gears, bolts and studs. It can be further surface-hardened-typically to 50-55 HRC by induction processes, producing components with enhanced wear resistance. For such applications the use of EN8D (080A42) is advisable. It is also available in a free-machining version, EN8M (212A42)
EN8 in its heat treated forms possesses good homogeneous metallurgical structures, giving consistent machining properties.
Good heat treatment results on sections larger than 63mm may still be achievable, but it should be noted that a fall-off in mechanical properties would be apparent approaching the centre of the bar.
It is therefore recommended that larger sizes of EN8 are supplied in the untreated condition, and that any heat treatment is carried out after initial stock removal. This should achieve better mechanical properties towards the core.
| 080M40 (EN8) Specification Chemical composition |
|
|---|---|
| Carbon | 0.36-0.44% |
| Silicon | 0.10-0.40% |
| Manganese | 0.60-1.00% |
| Sulphur | 0.050 Max |
| Phosphorus | 0.050 Max |
| Chromium | – |
| Molybdenum | – |
| Nickel | – |
| 080M40 (EN8) – mechanical properties in “R” condition | ||
|---|---|---|
| Max Stress | 700-850 n/mm2 | |
| Yield Stress | 465 n/mm2 Min | (up to 19mm LRS) |
| 0.2% Proof Stress | 450 n/mm2 Min | (up to 19mm LRS) |
| Elongation | 16% Min | (12% if cold drawn) |
| Impact KCV | 28 Joules Min | (up to 19mm LRS |
| Hardness | 201-255 Brinell | |
| EN8 Equivalents | |
|---|---|
| BS970: 1955 | EN8 |
| BS970/PD970: 1970 onwards |
080M40 |
| European | C40, C45, Ck40,Ck45, Cm40, Cm45 |
| Werkstoff No. | 1.0511, 1.1186, 1.1189 |
| US SAE (AISI) | 1039, 1040, 1042, 1043, 1045 |
We are Center is a supplier of EN8, EN8D and EN8M steel to local and national businesses. We stock EN8 in bright bar and blocks and black bar, square, flats and blocks.
