EN8 Steel

EN8 Steel

EN8 Steel Property

  • BS970:1955 : EN8
  • European Standard: C40, C45, Ck40,Ck45, Cm40, Cm45
  • Hardness: 201-255 Brinell

Refer EN8 Material Chemical Composition, Equivalent and Mechanical Properties

EN8 Steel is an unalloyed medium carbon steel alloy which contain 0.35% to 0.45% Carbon Content. Refer the Chemical Composition of EN8 (080M40) as per BS 970 1955 EN.

Table of contents

EN8 Chemical Composition

EN8 Chemical Composition

EN8 (080M40) Engineering Steel
As per BS 970 1955
EN8 Chemical Composition carbon (C) manganese (Mn) silicon (Si) Cr Ni sulfur (S) phosphorus (P)
% % % % % % %
.35%-.45% .60-1.0 .10-.35 – – .05 max .05 max

Other engineering steel grades:

  • En1A (220M07)
  • En3B (070M20)
  • En8 (080M40)
  • En9 (070M55)
  • En14A (150M19)
  • En16 (605m36)
  • En19 (708M40)
  • En24 (817M40)
  • EN24T (817M40T)
  • En36 (655M13)

Technique of Welding En8 Steel using MIG Wire and Electrode

  • Charpy Impact Test Machine
  • Scanning Electron Microscope (SEM)
  • Experimental Detail
  • Optical Fractography Testing Result

Compare Yield and Tensile Strength of EN8 Carbon Steel in Normalised and Cold Drawn Conditions

Condition Yield Stress
* 106 Pa		 Elongation % Tensile Stress MPa
Normalised 280 16 550
Cold drawn (thin) 530 7 660
Check Applications of BS970 080m40 Material
  • Gears
  • Bolts & Studs
  • General-Purpose Axles
  • Shafts
  • Spindles
  • Automotive & General Engineering Components
  • Other General Engineering Parts
EN8 vs EN9 Steel Rockwell Hardness Test

EN8 vs EN9 Steel Rockwell Hardness Test

TESTS EN8 EN19
T-1 34 19
T-2 37 21
T-3 34 23
T-4 38 24
T-5 37 19

EN8 Material Full Form

EN8 stands for European Norm 8

Specification of EN8 Steel

BS970: 1955 EN8
BS970/PD970 080M40
European Standard C40, C45, Ck40,Ck45, Cm40, Cm45
Werkstoff No. 1.0511, 1.1186, 1.1189
US SAE (AISI) 1039, 1040, 1042, 1043, 1045

Yield Strength Of En8

Yield Strength 280 to 540 MPa

En 8 Mechanical Properties

Yield Stress 465 n/mm2 Min (up to 19mm LRS)
Impact KCV 28 Joules Min (up to 19mm LRS)
Hardness 201-255 Brinell
0.2% Proof Stress 450 n/mm2 Min (up to 19mm LRS)
Elongation 16% Min (12% if cold drawn)
Max Stress 700-850 n/mm2

Tensile Strength Of En8

Tensile Stress 550 MPa

En8 Equivalent Material

EU
EN		 USA
–		 Germany
DIN,WNr		 Japan
JIS		 France
AFNOR		 England
BS		 Italy
UNI		 China
GB		 Poland
PN		 Czechia
CSN		 Russia
GOST		 Inter
ISO
C40
(1.0511)		 1038
1040		 1.0511
C40
Ck40		 S40C AF60C40
AF60C45
XC42HI		 070M40
080M40
En8		 C40 40 40 12041 40 C40
C40E4

Heat Treatment Of En8 Steel

Soft annealing 680 – 710°C/furnace
Normalising 840 – 880°C/air
Hardening 820 – 860°C/water, oil
Tempering 550 – 660°C/air

En8 Hardness

Hardness 170-200 BHN

En8 Equivalent Indian Standard

ISO C40E4

Machining Time of EN8 Steel Material

Machining Time of EN8 Steel Material

Carbon Steel Grade EN8 Forging

Forging or hot rolling 1100 – 850°C

Available product range of EN8 steel

EN8 steel Plate and Sheet
Strips thickness 0.4mm to 4mm
Sheets (cold rolled) thickness 0.4mm to 4mm
Sheets (hot rolled) thickness 2.7mm to 12mm
Plates 16mm to 150mm
Heavy plates 16mm to 350mm
1045 Steel Round Bar
Rolled round bar diameter 16mm to 250mm
Heavy forged round diameter 200mm to 450mm
Heavy machined round diameter 260mm to 620mm
Heavy ship shafts diameter 450mm to 1000mm
S45C Flat Bar
Rolled flat bar thickness upto 50mm
width upto 455mm
Forged flat bar thickness upto 305mm
width upto 455mm

DIN 1.0511 Thermal Properties

Thermal conductivity Thermal co-efficient
37.5 W/m K 6.5e-6 W/m K.

Annealing of 080M40 grade steel

Annealing 680-710°C

C45 grade Surface Finish & Tolerance

Surface Finish Turned Black-Rolled Polished Grinding Cold Drawn Black-Forged Peeled
Tolerance (0，+3mm) (0，+1mm) Best h11 Best h9 Best H11 (0，+5mm) Best H11

Surface hardness of S45C steel

Surface hardness min. 55 HRC

Testing method for 1045 steel

  • Corrosion Testing
  • Chemical Composition Analysis
  • Tensile Strength Test
  • Ultrasonic Testing
  • Visual Inspection
  • Bend Test