Alloy Q+T Steels | ELECTROMETAL S.A.

Category 02

Quenched & Tempered

Alloy quenched and tempered steels undergo thermal treatment (Quenching + Tempering) at the producing steel mill, achieving the optimal combination of strength, hardness and toughness.

They are the grade of choice for high-load shafts, crankshafts, power transmission components and critical-reliability constructions in shipbuilding, oil & gas, mining and heavy machinery.

We stock two main grades — 42CrMo4 and 34CrNiMo6 — in round bars from Ø16 to Ø450 mm, with EN 10204 3.1 certificates. 30CrNiMo8 (1.6580) is also available on order.

Q+T

Quenched +
Tempered

Available Grades

Grades

Grade	W.Nr.	Standard	Alloy	Application	Availability
42CrMo4	1.7225	EN 10083-3	Cr-Mo	Shafts, crankshafts, gears	In stock
34CrNiMo6	1.6582	EN 10083-3	Ni-Cr-Mo	High-load shafts, crankshafts	In stock
30CrNiMo8	1.6580	EN 10083-3	Ni-Cr-Mo	Heavy components, large sections	On order

Spotlight

42CrMo4

42CrMo4 / 1.7225

The most widely used alloy quenched and tempered steel in industry. Combines high strength, good machinability and satisfactory toughness.

Chemical Composition (wt%)

0.38–0.45

≤ 0.40

0.60–0.90

0.90–1.20

0.15–0.30

≤ 0.025

≤ 0.035

Mechanical Properties (Q+T)

Diameter	Re (MPa)	Rm (MPa)	A (%)	HB
≤ Ø16	900	1100–1300	10	320–380
Ø16–Ø40	750	1000–1200	11	290–350
Ø40–Ø100	650	900–1100	12	270–320
Ø100–Ø160	550	800–950	13	240–290
Ø160–Ø250	500	750–900	14	225–275

Identification mark: Black / Yellow

Spotlight · 34CrNiMo6

34CrNiMo6 / 1.6582

With 1.4–1.7% Nickel content, 34CrNiMo6 offers superior resistance to dynamic loads compared to 42CrMo4. It is the grade of choice for marine engine crankshafts, turbine components and heavy-duty shafts.

The Cr and Mo content ensures high hardenability even in large diameters (above Ø250 mm), maintaining uniform mechanical properties throughout the cross-section.

C: 0.30–0.38%
Cr: 1.30–1.70%
Ni: 1.40–1.70%
Mo: 0.15–0.30%

Identification mark: Yellow

Applications

Typical Applications

Crankshafts

Diesel engines, marine engines, industrial compressors — critical-reliability components.

Transmission Shafts

High-load shafts, gear components, pinions, pump rotors.

Oil & Gas

Drill collars, high-strength bolts, fittings, offshore constructions.

Heavy Machinery

Mining equipment components, industrial presses, large-dimension bearings.

Need Q+T Steels?

All grades in Q+T condition, with EN 10204 3.1 certificates.

Request Quote →Case-Hardening →

Alloy Q+T Steels42CrMo4, 34CrNiMo6 — quenched and tempered steels for high-load shafts and critical-reliability components.