42CrMo4 is an alloy Cr-Mo quenched and tempered steel to EN 10083-3. It is hardened and tempered. Chromium and molybdenum give hardenability in moderate cross-sections.

What Werkstoffnummer does 42CrMo4 have?

W.Nr. 1.7225. The same grade can appear on the drawing as 42CrMo4, 1.7225 or both.

What does 42CrMo4 +QT mean?

+QT is hardened and tempered – quenched and tempered. Most orders are specified in that condition. The hardness must be stated on the PO if the requirement is more than “+QT”.

What is 42CrMo4 used for?

Shafts, pins, gear parts, bolts and mechanically loaded machine components. Hydraulic parts when the drawing specifies 42CrMo4 or 1.7225.

Can 42CrMo4 be cut to size?

Yes. Sawing is standard, also in large diameters. Boring and heat treatment are ordered when the drawing requires it. State length and machining allowance.

Is 42CrMo4 the same as AISI 4140?

No, not automatically. AISI/SAE 4140 is a closely related American grade that is often cross-referenced to 42CrMo4 / 1.7225. Chemical composition, mechanical properties and delivery condition must be checked against the actual specification and the material certificate before substitution.

What is the difference between 42CrMo4 and 42CrMoS4?

42CrMo4 (1.7225) and 42CrMoS4 (1.7227) belong to the same chromium-molybdenum family to EN 10083-3. The S variant 42CrMoS4 has raised sulphur for improved machinability and its own Werkstoffnummer 1.7227.

Quenched and tempered steel

42CrMo4 / 1.7225 round bar – cut to size

1.7225 is the Werkstoffnummer for 42CrMo4. 42CrMo4 is a chromium-molybdenum quenched and tempered steel to EN 10083-3. We cut round bar to size, including single cut pieces, and deliver with EN 10204 3.1. Send diameter, length and drawing, and we come back with a price.

Request a quote +45 77 34 00 96

Designations

W.Nr.: 1.7225
EN standard: 42CrMo4
DIN: 42CrMo4
AISI/SAE: 4140
SS (Sweden): 2244
UNS: G41400
JIS: SCM440
Group: Alloy engineering steel

Mechanical properties

Typical +QT values according to EN 10083-3

+QT, round bar. Values fall as the ruling section increases.

Ruling section	Re min.	Rm	A min.
d ≤ 16 mm	900 MPa	1100–1300 MPa	10 %
16–40 mm	750 MPa	1000–1200 MPa	11 %
40–100 mm	650 MPa	900–1100 MPa	12 %
100–160 mm	550 MPa	800–950 MPa	13 %

Impact toughness is typically around 35 J in the same ranges. Mechanical table values apply to the stated ruling sections. Larger diameters in the delivery programme do not automatically have the same core values as Ø16.

Chemical composition

Typical range according to EN 10083-3 (ladle analysis)

Element	Range
C	0.38–0.45 %
Si	max. 0.40 %
Mn	0.60–0.90 %
P	max. 0.025 %
S	max. 0.035 %
Cr	0.90–1.20 %
Mo	0.15–0.30 %

42CrMoS4 has raised sulphur for machining. Same chromium-molybdenum framework.

Typical applications

Shafts and pins
Gear and transmission parts
Hydraulic and machine components
Forged and turned rings
Bolts and fasteners
Mechanically loaded machine parts

Delivery conditions and dimensions

42CrMo4 / 1.7225 can be supplied in a wide dimension programme via partner stock and delivery programme – typically from Ø10 to Ø1300 mm depending on delivery condition and requirements. This is not a statement of current stock in every diameter. Production route (rolled or forged) depends on diameter and mill. Full lengths and cut pieces to size as required. Stock status is confirmed on enquiry.

+QT
42CrMoS4 for machining
Full lengths and cut pieces
Flat bar, square bar and forgings to size

Heat treatment of 42CrMo4

42CrMo4 is hardened and tempered. Hardening raises the strength; tempering gives toughness, so the part can take load without becoming brittle. +QT – quenched and tempered – is the condition most orders are specified in. Normalising or soft annealing may be relevant before rough machining, but only when agreed. Furnace temperatures are not given here: they belong to the mill's procedure and the specified hardness. Mechanical values fall with increasing ruling section.

Machinability

42CrMo4 is machined in +QT, but tool wear has to be planned for. 42CrMoS4 / 1.7227 is the sister variant with raised sulphur for machining – same Cr-Mo framework, different Werkstoffnummer. Sawing and rough machining should take place before final hardness if the drawing allows.

Weldability

Not a welding steel like S355. Welding requires preheating and a procedure and must be clarified before it is specified.

Sawing and machining

We cut to size – single pieces and series – from a single cut piece to larger series without minimum charge. Large diameters are part of the delivery programme. Boring removes the core when the part is to be a ring or a heavy tube. Heat treatment to agreed hardness or +QT is ordered when the drawing requires it. Large diameters may be forged; that describes the production route, not a ceiling for the range. The grade can also be supplied deep-hole drilled to size: state outside diameter, bore diameter and length.

Documentation – 42CrMo4 with EN 10204 3.1 certificate

EN 10204 3.1 is included as standard – at no charge. Documentation follows the certificate issued by the mill and the requirements specified in the order. 3.2 and classification society are documented only when specified.

International designations

AISI/SAE 4140 is a closely related American grade that is often cross-referenced to 42CrMo4 / 1.7225. EN19 / 708M40 and SCM440 are British and Japanese designations in the same Cr-Mo family. They are closely related or frequently cross-referenced – not identical. Chemical composition, mechanical properties, heat treatment and delivery condition must be checked against the actual specification and the material certificate before substitution. The certificate carries the name the mill has issued.

42CrMo4 / 1.7225 – EN designation and Werkstoffnummer
AISI 4140 / SAE 4140 – closely related American grade, often cross-referenced
EN19 / 708M40 – British BS 970 designation in the same Cr-Mo family
SCM440 – Japanese JIS designation in the same Cr-Mo family
42CrMoS4 / 1.7227 – same Cr-Mo framework with raised sulphur for machining

42CrMo4 vs 34CrNiMo6

Both are quenched and tempered shaft steels. 42CrMo4 is Cr-Mo without nickel. 34CrNiMo6 is Cr-Ni-Mo. For larger cross-sections and high requirements for through-hardening and toughness, 34CrNiMo6 / 1.6582 can be a relevant alternative. The choice depends on dimension, load, heat treatment, through-hardening, strength, toughness and design requirements. Neither material is universally better, and one cannot automatically replace the other. Substitution should only be considered when diameter, strength requirement and certificate support it.

Delivery: rings for Everllence

We supply forged 42CrMo4 rings to Everllence – formerly MAN Diesel SE – for the production of piston rings. The rings are forged, rolled and turned to size. The delivery is part of a larger, ongoing collaboration.

Frequently asked questions

What is 42CrMo4?: 42CrMo4 is an alloy Cr-Mo quenched and tempered steel to EN 10083-3. It is hardened and tempered. Chromium and molybdenum give hardenability in moderate cross-sections.
What Werkstoffnummer does 42CrMo4 have?: W.Nr. 1.7225. The same grade can appear on the drawing as 42CrMo4, 1.7225 or both.
What does 42CrMo4 +QT mean?: +QT is hardened and tempered – quenched and tempered. Most orders are specified in that condition. The hardness must be stated on the PO if the requirement is more than “+QT”.
What is 42CrMo4 used for?: Shafts, pins, gear parts, bolts and mechanically loaded machine components. Hydraulic parts when the drawing specifies 42CrMo4 or 1.7225.
Which dimensions can 42CrMo4 be supplied in?: 42CrMo4 / 1.7225 can be supplied in a wide dimension programme via partner stock and delivery programme – typically from Ø10 to Ø1300 mm depending on delivery condition and requirements. Stock status is confirmed on enquiry. Send diameter, length, quantity and required delivery condition.
Can 42CrMo4 be cut to size?: Yes. Sawing is standard, also in large diameters. Boring and heat treatment are ordered when the drawing requires it. State length and machining allowance.
Can 42CrMo4 be supplied with EN 10204 3.1?: Yes. EN 10204 3.1 is included as standard and at no charge. Documentation follows the certificate issued by the mill and the requirements specified in the order.
Is 42CrMo4 the same as AISI 4140?: No, not automatically. AISI/SAE 4140 is a closely related American grade that is often cross-referenced to 42CrMo4 / 1.7225. Chemical composition, mechanical properties and delivery condition must be checked against the actual specification and the material certificate before substitution.
What is the difference between 42CrMo4 and 42CrMoS4?: 42CrMo4 (1.7225) and 42CrMoS4 (1.7227) belong to the same chromium-molybdenum family to EN 10083-3. The S variant 42CrMoS4 has raised sulphur for improved machinability and its own Werkstoffnummer 1.7227.

More grades and dimensions in Danish

Looking for 42CrMo4 / 1.7225?

42CrMo4 / 1.7225 can be supplied via partner stock and delivery programme in typically Ø10–Ø1300 mm. Send diameter, length, quantity and required condition – we reply in English. Stock status is confirmed on enquiry.