EN19 (also known as AISI 4140 / 1.7225) is a high-tensile, chromium–molybdenum alloy steel known for its excellent strength, toughness, wear resistance, and fatigue performance. It is one of the most widely used alloy steels in engineering and automotive sectors, particularly for high-stress, high-load components. EN19 combines high mechanical strength with good ductility and impact resistance. It offers better performance than EN8 and EN9 and is often chosen as a cost-effective substitute for EN24 where very high strength is not mandatory.

Key Properties of EN19 Steel

1. High Tensile Strength

EN19 delivers a tensile strength of 850–1000 MPa in the normalized condition, and even higher after heat treatment.

2. Exceptional Toughness & Fatigue Resistance

Ideal for components subjected to continuous cyclic loading, shock loads, and torsional stress.

3. Excellent Hardenability

EN19 can be heat-treated to achieve:
a. Hardness: 28–36 HRC (normalized)
b. Heat treated: 40–50 HRC
c. Induction hardened: 55+ HRC surface hardness
This makes it suitable for high-strength shafts and mechanical parts.

4. Good Machinability

Machinable in both normalized and tempered conditions.

5. Good Weldability (With Precautions)

Requires preheating (200–300°C) and post-weld heat treatment due to the alloying elements.

Typical Applications

EN19 is widely used in automotive, machinery, construction, manufacturing, mining, agriculture, and oil & gas sectors.

Common applications include:
1. High-strength shafts, gear shafts & spline shafts
2. Studs, bolts & high-tensile fasteners
3. Crankshafts, camshafts & connecting rods
4. Machine tool spindles
5. Axles, driveshafts & propeller shafts
6. Gears, pinions & couplings
7. Rock drilling parts & downhole tools
8. Mandrels, rams & press parts
9 High-stress mechanical components
10. Load-bearing industrial components

Why Choose EN19?

EN19 is the perfect balance between cost, strength, wear resistance, and durability, making it one of the most popular alloy steels used across industries. Its versatility and ability to be heat-treated to a variety of hardness levels make it suitable for premium, long-lasting engineering components.