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EN8 (080M40 / 080A42)

Medium Carbon Steel

EN8 Bright & Black Bar

EN8 is a medium carbon steel which is used in applications where better properties than mild steel are required, at a lower cost than an alloy, making this an excellent alternative to alloy.

This is an unalloyed carbon steel with reasonable tensile strength. Heat treating EN8 engineering steel provides a good surface hardness. It can be flame or induction hardened and is a readily machinable steel.

Although EN8 steel is capable of through hardening by quenching and tempering, it is more commonly supplied in the untreated or normalised condition. It possesses good wear resistance, but reduced weldability.

Heat treatment of EN8 steel

When heat treated, EN8 offers moderate wear resistance. It shares the same good mechanical properties of EN16 | 605M36T steel which is more resistant to shear loading and frictional wearing. EN8 can be tempered at a heat of between 550 °C to 660 °C, heating for about 1 hour for every inch of thickness before being cooled in oil or water. Normalising of EN8 bright Mild Steel takes place at 830-860 °C.

Did you know C45 / C40 are European steel grades offering similar characteristics and suitable for similar applications as EN8?

In conclusion, EN8 steel is suitable for all general engineering applications requiring a higher strength than mild steel. If you are unsure about which is the right steel for a specific application, call 01457 866911 and talk to one of our expert Sales Team.

Stock range

High Peak Steels stock EN8 round bar, EN8 flat bar and EN8 square bar.

Associated standards

UK Standard EN8 | European Grades C40 / C45 | Werkstoff 1.0511 | SAE/AISI 1040

EN8 availability

EN8 PRICES & STOCK

Typical Applications

  • AUTOMOTIVE PARTS
  • CONNECTING RODS
  • STUDS, BOLTS
  • AXLES, SPINDLES
  • GENERAL ENGINEERING COMPONENTS

EN8 | 080M40 Steel size ranges

Cross sectionProductMin sizeMax size
codes-round2 EN8 round bar25mm dia800mm dia
codes-flat2EN8 flat bar
codes-square2EN8 square bar75mm200mm Billet SQ
codes-hex2EN8 hex bar

EN8 | 080M40 Chemical Composition

CSiMnSPCrNiMo
Min0.360.10.6
Max0.440.410.050.050.30.40.15

EN8 | 080M40 Mechanical Composition

Yield
N/mm2
0.2% proof
N/mm2
UTS (Rm)
N/mm2
Elong (A)
%
Red of Area (Z)
%
Hardness
HB
Impact Test (KV)
J
Normalised (min)2805501615216
Normalised (max)207
Drawn (min)5106508
Drawn (max)
Quenched & Tempered to condition Q (min)3856251617928
Quenched & Tempered to condition Q (max)229

EN8 | 080A42 Steel size ranges

Cross sectionProductMetric sizes
Min
MaxImperial sizes
Min
Max
codes-round2EN8 round bar5mm dia200mm dia1/4" dia8" dia
codes-flat2EN8 flat bar8mm x 7mm Key Steel50mm x 28mm Key Steel5/16" x 1/4" Key Steel2" x 1 1/2" Key Steel
codes-square2EN8 square bar4mm SQ Key Steel50mm SQ Key Steel3/16" SQ Key Steel2" SQ Key Steel
codes-hex2EN8 hex bar

EN8 | 080A42 Chemical Composition

CSiMnSPCrNiMo
Min0.40.10.7
Max0.450.40.90.050.050.30.40.15

For more information on EN8 medium carbon steel Please get in touch

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