Case-Hardening Steel

20MnCr5 · 1.7147

Also known as 5120 (near)

Higher-strength case-hardening steel for heavily loaded gears.

20MnCr5 (material 1.7147) is a chromium-manganese case-hardening steel with higher core strength than 16MnCr5, used for heavily loaded gears, shafts and transmission parts. Supplied as hot-rolled and cold-drawn bar.

International equivalents.

The same steel by country and standard — near matches; mill certificate governs.

20MnCr5 (1.7147) · EN 5120 (near) · AISI / SAE 20MnCr5 · GB

Chemical composition.

Indicative, % by weight per EN 10084. Mill certificate governs.

Element%
C 0.17 – 0.22
Si ≤ 0.40
Mn 1.10 – 1.40
Cr 1.00 – 1.30
P ≤ 0.025
S ≤ 0.035

Mechanical properties.

Indicative values for a reference section and heat-treatment condition. Actual properties vary with dimension and treatment, and are confirmed on the mill certificate.

Core tensile (Rm)
1000 – 1300 MPa (hardened)
Surface hardness
≈ 58 – 62 HRC
Hardness (annealed)
≤ 217 HB

Available forms.

Round bar Bright / cold-drawn bar

Size: Ø 6 – 250 mm

Typical applications.

  • Heavily loaded gears
  • Gear shafts
  • Transmission parts
  • Bearings races
Standards: EN 10084

FAQ.

What is 20MnCr5?

20MnCr5 (material 1.7147) is a chromium-manganese case-hardening steel with higher core strength than 16MnCr5, used for heavily loaded gears, shafts and transmission parts. Supplied as hot-rolled and cold-drawn bar.

Is 20MnCr5 the same as 5120 (near)?

Yes — 20MnCr5 and 5120 (near) are matching designations for the same steel across different standards (EN, AISI/SAE, JIS, GB, former DIN). They are near equivalents and may differ slightly in chemistry, so the mill certificate governs the exact specification.

What are the international equivalents of 20MnCr5?

20MnCr5 corresponds to 20MnCr5 (1.7147) (EN), 5120 (near) (AISI / SAE), 20MnCr5 (GB). Equivalents are nearest matches by country/standard; the mill certificate governs the exact specification.

In which forms is 20MnCr5 available?

20MnCr5 is supplied as Round bar, Bright / cold-drawn bar, in Ø 6 – 250 mm.

What is 20MnCr5 used for?

Typical applications include Heavily loaded gears, Gear shafts, Transmission parts, Bearings races.