EN19 vs EN24 — Which High-Strength Engineering Steel Performs Better in 2025? (Complete Technical Comparison Guide)

EN19 and EN24 are two of the most powerful and widely used alloy steels in modern engineering. Both steels deliver exceptional mechanical performance, making them ideal for:

• Automotive components
• Oil & gas machinery
• Heavy-duty equipment
• Aerospace parts
• High-load shafts & gears
• Power transmission components

But the big question remains:
Which steel is better — EN19 or EN24?

Both offer excellent strength, heat treatment response, and wear properties, but each grade has specific advantages. In this detailed 2025 comparison guide, we break down the differences in:

• Mechanical properties
• Heat treatment performance
• Wear resistance
• Impact toughness
• Machinability
• Best industry applications
• Cost & long-term reliability

By the end of this article, you will know exactly which material is right for your project.

Chemical Composition — The Root of Their Strength

Property	EN19 (4140 Equivalent)	EN24 (4340 Equivalent)
Carbon	0.38–0.43%	0.36–0.44%
Chromium	0.9–1.2%	0.9–1.4%
Molybdenum	0.15–0.25%	0.2–0.3%
Nickel	—	1.3–1.8%

Key Difference: EN24 contains Nickel, which dramatically increases:

Toughness
Impact resistance
Fatigue strength
Shock absorption

Mechanical Properties Comparison

Property	EN19	EN24
Tensile Strength	850–1000 MPa	1000–1400 MPa
Yield Strength	600–800 MPa	800–1000 MPa
Hardness (HRC)	28–32	32–48
Fatigue Strength	High	Very High
Impact Toughness	High	Extremely High

Summary:

EN19 → Strong, balanced, economical
EN24 → Stronger, more shock resistant, premium grade

If your application faces impact loads, EN24 wins clearly.

Heat Treatment Capabilities — EN24 Dominates

EN19 and EN24 both respond excellently to heat treatment. But EN24 provides superior hardness & toughness due to its Nickel content.

EN19 Heat Treatment

Great hardenability
Excellent for gears, shafts
Moderate through-hardening

EN24 Heat Treatment

Deep hardening
Very high impact strength
Exceptional stability after tempering
Best for dynamic loads

Winner for heat treatment: EN24

Wear Resistance — EN24 Performs Better

Wear resistance is critical for gears, shafts, and high-friction parts.

EN19 → Good wear resistance
EN24 → Outstanding wear resistance (even under extreme load)

⭐ Winner: EN24

Impact & Shock Resistance

This is the biggest performance difference.

⭐ EN19
Strong, reliable, handles moderate impact.

EN24 Built for extreme impact applications such as:

Aircraft components
Racing vehicles
Mining equipment
High-load rotating machines

EN24’s Nickel content makes it highly resistant to brittle failure under sudden shock.
⭐ Winner: EN24 by a large margin

Machinability — EN19 Is Better

EN24 becomes harder & tougher after heat treatment, making machining more difficult.

Grade	Machinability
EN19	⭐⭐⭐⭐ (Good)
EN24	⭐⭐⭐ (Average / Difficult after hardening)

If machining cost & time matter, EN19 is the better choice.

Corrosion Resistance

Both EN19 and EN24 are not corrosion-resistant steels unless coated.

However, EN24 has slightly better atmospheric resistance due to Nickel.

For corrosion-critical applications → choose Stainless Steel or Duplex.

Applications — Where Each Grade Is Best Used

Where EN19 Is Used (4140)

EN19 offers the best balance of strength + affordability.

Automotive crankshafts
Gear shafts & pinions
Propeller shafts
High-load bolts & studs
Drill collars
Connecting rods
General engineering components

Where EN24 Is Used (4340)

Aircraft landing gear
Missile & defense components
Helicopter rotor shafts
Racing vehicle drivetrain parts
Mining machinery
Heavy industrial shafts
Performance gears

If failure is not an option → EN24 is the choice.

Cost & Availability Comparison

Grade	Cost	Availability	When to Choose
EN19	Medium	Widely available	Balanced performance
EN24	Higher	Available but premium	Extreme strength demands

EN24 gives superior performance, but EN19 provides the best value for the price.

Which Should You Choose? (Simple Selection Guide)

Choose EN19 if:

You need strong, reliable, cost-effective steel
Machinability is important
Application involves moderate to heavy load
Budget matters

Choose EN24 if:

You need maximum strength
Application involves shock, impact, or high torque
You want long-term durability under extreme stress
You are designing for aerospace, racing, mining, or defense

Conclusion

EN19 and EN24 are both outstanding engineering steels, but serve different performance levels:

EN19 → the best all-rounder — strong, affordable, machinable, and reliable.
EN24 → the premium high-performance steel — unmatched strength, toughness, and wear resistance.

Industries choose EN19 for economical high strength, and EN24 for extreme mechanical demands where failure cannot be tolerated.

For both EN19 and EN24, Moksh Tubes & Fittings LLP offers precision-engineered bars, rods, forgings, and machined components compliant with global standards.

FAQ's

Which steel is stronger: EN19 or EN24?

EN24 is significantly stronger due to its nickel-chromium-molybdenum composition.

Is EN24 harder than EN19?

Yes — EN24 achieves higher hardness after heat treatment.

Which is easier to machine?

EN19 is easier and more cost-effective to machine.

Is EN24 worth the extra cost?

Yes, if your application demands high strength, shock resistance, and durability.

Can EN19 and EN24 replace each other?

Sometimes yes — but EN24 should be chosen for critical, high-impact applications.

At Moksh Tubes & Fittings LLP, we’re dedicated to making your purchases seamless — offering expert advice, a wide inventory of certified products, and global support for every order, large or small.

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