EN 19

Grade Introduction:

EN19 Steel is a high-quality engineering alloy steel containing chromium and molybdenum. It falls in a class of low alloy steel. It has high fatigue strength, abrasion and impact resistance, toughness, and torsion strength. It can be heat treated in a number of ways to give it a combination of properties. EN19 Steel is one steel grade in BS 970-1955 standard, which is the specification for wrought steels for mechanical and allied engineering purposes.

Grade Application:

EN19 Alloy steel was originally introduced for use in the machine tool and motor industries for gears, pinions, shafts, spindles, and the like. Later its applications became much more extended and it is now widely used in areas such as the oil and gas industries. EN19 is suitable for applications such as gears, bolts, studs, and a wide variety of applications where a good quality high tensile steel grade is suited.

Equivalent grades:

Internal Standard BS Din IS EN Sae/Aisi
EN19 709M40 42CrMo2 40Cr4Mo3 En19 4140

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

Heat Treatment Properties:

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 alloy steel can be hardened by cold working or heating and quenching.