EN19 – BRIGHT BAR Grade Introduction:

EN19 steel bright round bar also known as AMERICAN SAE 4140 round bar. EN 19 Bright  Round Bar is a 1% chromium – molybdenum medium hardenability general purpose high tensile steel – generally supplied hardened and tempered in the tensile range of 850 – 1000 Mpa (condition T). All our 4140 Alloy Steel Bar supplied is Ultrasound and MPI inspected. EN19 bright bar is a high quality alloy steel with tensile strength. It is a high quality medium carbon. EN19 black bar is one steel grade in BS 970-1955 standard, which is specification for wrought steels for mechanical and allied engineering purpose. With a combination of good ductility and shock resistance, EN19 bar and en 19 flat bar is suitable for applications with very high loading such as engine gear boxes. EN19 square bar is a popular material in the automotive sector it is possible to machine the material extremely accurately. EN19 hollow bar material is also in demand by Oil & Gas industry. EN19 steel bar is a prime choice because of its high strength. The EN19 rod equivalent grades are AISI 4140 Rod, DIN 1.7225/42crmo4 Bar.
EN19 steel bright round bar is an engineering alloy steel containing chromium and molybdenum. EN19 welding rod comes under the class of low alloy steel. EN19 round bars have high fatigue strength, abrasion and impact resistance, toughness, and torsional strength. EN19 black bars can be heat treated in a number of ways to give it a combination of properties. Oil Quenched & Tempered Hardness is 28-34 HRc.  EN19 bright bar Annealing delivery hardness is less than 250HB. En19 round bar has high tensile strength of 850- 1000 Mpa. 
EN19 – BRIGHT BAR Grade Application:
  • Utilized when higher than carbon steel mechanical properties are required
  • Commonly used for axles, drive shafts, crankshaft connecting rods, high tensile bolts, studs, propeller shaft joints, rifle barrels, and induction hardened pins
  • Bolt specification: 9.8 (in condition “T”)
  • Bolt specification: 10.9 (in condition “U”)
  • Gears
  • Pinions
  • Shafts
  • Spindles
  • Oil & Gas Industries
 
EN19 – BRIGHT BAR Equivalent grades:
Internal Standard
BS
Din
IS
EN
Sae/Aisi
EN19
709M40
42CrMo2
40Cr4Mo3
En19
4140
EN19 – BRIGHT BAR Chemical Composition: 
The following table shows the chemical composition of EN19 steel:
Element
C
Si
Mn
P
S
Cr
Mo
Fe
Content (%) 
0.35-0.45
0.15-0.30
0.50 – 0.80
0.035
0.040
0.90-1.50
0.20-0.40
96.78-97.77
 
EN19 – BRIGHT BAR Mechanical Properties:
Properties
Metric
Imperial
Tensile strength
655 MPa
95000 psi
Yield strength
415 MPa
60200 psi
Bulk modulus (typical for steel)
140 GPa
20300 ksi
Shear modulus (typical for steel)
80 GPa
11600 ksi
Elastic modulus
190-210 GPa
27557-30458 ksi
Poisson’s ratio
0.27-0.30
0.27-0.30
Elongation at break (in 50 mm)
25.70%
25.70%
Hardness, Brinell
197
197
Hardness, Knoop (converted from Brinell hardness)
219
219
Hardness, Rockwell B (converted from Brinell hardness)
92
92
Hardness, Rockwell C (converted from Brinell hardness. Value below normal HRC range, for comparison purposes only)
13
13
Hardness, Vickers (converted from Brinell hardness)
207
207
Machinability (based on AISI 1212 as 100 machinability)
65
65
EN19 – BRIGHT BAR Hardness: 
Properties
Metric
Imperial
Hardness, Brinell
197
197
EN19 – BRIGHT BAR Heat treatment: 
Steel is heated at 845°C followed by quenching in oil. Before hardening, it can be normalized by heating at 913°C for a long period of time followed by air cooling.
 
EN19 – BRIGHT BAR Hardening:
Oil quench from a temperature of 85°C/88°C Celsius.
EN19 – BRIGHT BAR Tempering:
En19 alloy steel can be tempered at 205 to 649°C depending upon the desired hardness level. The hardness of the steel can be increased if it has lower tempering temperature. For example, tensile strength of 225 ksi can be achieved by tempering at 316°C (600°F), and a tensile strength of 130 ksi can be achieved by tempering at 538°C(1000°F).
EN19 – BRIGHT BAR Physical Properties:
DENSITY (G/CM 3)
8.08
DENSITY (LB/IN 3)
0.292
MELTING POINT (°C)
1425
MELTING POINT (°F)
2600
EN19 – BRIGHT BAR Thermal Properties: 
Average Coefficient of Linear Thermal Expansion (μm/m.K)
Temp. Range °C
20-100
20-200
20-400
20-600
Coefficient
12.2
12.6
13.7
14.6
Electrical Resistivity (  μΩ.m) and Thermal Conductivity (W/m.K)
Temp. Range °C
100
200
400
600
Electrical Resistivity
0.263
0.326
0.4575
0.646
Thermal Conductivity
42.6
42.2
37.7
33.0
 
EN19 – BRIGHT BAR Forging Properties:
Forge within the temperature range of 125°C/90°C Celsius.
EN19 – BRIGHT BAR Stress Reliving: 
Annealed: 600-650°c Heat in needed.
Hardened: 500-550°c Heat in needed.
EN19 – BRIGHT BAR Normalizing: 
Heat 870°C – 900°C and cool in still air.
EN19 – BRIGHT BAR Annealing: 
Anneal at a temperature of 85°C Celsius and cool steadily.
EN19 – BRIGHT BAR Density: 
Density of EN19 Alloy steel material: 7.85kg/cm3
EN19 – BRIGHT BAR Machinability: 
EN19 alloy steel has good machinability in the annealed condition.
EN19 – BRIGHT BAR Welding: 
EN19 steel can be welded using all conventional techniques. However, the mechanical properties of this steel will be affected if it is welded in the heat treated condition, and post weld heat treatment should be performed.