What is 42CrMo4V steel?
42CrMo4V is a trade name rather than a separate standard grade. The base steel is 42CrMo4 (1.7225) from EN 10083-3, a medium-carbon steel alloyed with about 1 % chromium and 0.2 % molybdenum. The suffix "V" comes from the German vergütet, meaning quenched and tempered. European standards write the same condition as 42CrMo4+QT. The V does not indicate added vanadium.
Quenching and tempering give the steel high tensile strength, good toughness and fatigue resistance through a deep hardened section. Molybdenum raises hardenability and reduces susceptibility to temper embrittlement. It is widely used for heavily loaded shafts, gears, rings and pressure parts.
42CrMo4V forged products we supply
All parts are open-die forged or ring rolled to the customer's drawing or size, then delivered annealed, normalized, or quenched and tempered as required.
| Product form | Typical use |
|---|---|
| Seamless rolled rings, forged rings | Pump, compressor, gearbox and turbine rings |
| Shafts, spindles, eccentric shafts, crankshafts | Pumps, gearboxes, compressors, cement and sugar mills |
| Flanges, tube sheets, forged nozzles | Pressure vessels, heat exchangers, columns, towers and tanks |
| Discs, bushings, forged sleeves | Offshore equipment, air compressors, power and nitrogen generators |
| Forged round bars | Gears, pins and machined components |
| Hollow forgings, pipes, tubes | Pressure vessels and air receivers |
| Valve stems, seat rings, bodies, blocks | Ball, gate, globe, check and plug valves; wellheads |
| Gears, wheels, rolls, manifolds | Gearboxes, shipbuilding, heavy machinery |
Chemical composition of 42CrMo4V
42CrMo4V has the same chemistry as 42CrMo4. Heat analysis limits in mass %:
| Grade | C | Si | Mn | P | S | Cr | Mo |
|---|---|---|---|---|---|---|---|
| 42CrMo4V | 0.38-0.45 | ≤ 0.40 | 0.60-0.90 | ≤ 0.025 | ≤ 0.035 | 0.90-1.20 | 0.15-0.30 |
Forgings can also be supplied to EN 10250-3. Tighter limits, for example lower phosphorus and sulphur, can be agreed at the enquiry stage.
Mechanical properties of 42CrMo4V
Strength depends on section size. The core of a thick forging cools more slowly during quenching, so the minimum values drop as the diameter increases.
| Diameter d (mm) | Yield Re min (MPa) | Tensile Rm (MPa) | Elongation A min (%) | Reduction Z min (%) | Impact KV min (J) |
|---|---|---|---|---|---|
| ≤ 16 | 900 | 1100-1300 | 10 | 40 | - |
| 16 < d ≤ 40 | 750 | 1000-1200 | 11 | 45 | 35 |
| 40 < d ≤ 100 | 650 | 900-1100 | 12 | 50 | 35 |
| 100 < d ≤ 160 | 550 | 800-950 | 13 | 50 | 35 |
| 160 < d ≤ 250 | 500 | 750-900 | 14 | 55 | 35 |
1 MPa = 1 N/mm². For heavy open-die forgings above 250 mm, properties are agreed per EN 10250-3 or the customer's specification and verified on test pieces taken from the forging or a prolongation.
Physical properties
| Property | Value |
|---|---|
| Density | 7.85 g/cm³ |
| Modulus of elasticity | approx. 210 GPa |
| Thermal conductivity | approx. 42 W/(m·K) |
| Thermal expansion (20-100 °C) | approx. 11.1 × 10⁻⁶ /K |
| Specific heat capacity | approx. 460 J/(kg·K) |
Forging and heat treatment of 42CrMo4V
We deliver 42CrMo4V forgings annealed, normalized, or hardened and tempered, according to the customer's needs. Typical temperature ranges:
| Process | Temperature | Cooling | Result |
|---|---|---|---|
| Hot forging | Start approx. 1150 °C, finish ≥ 850 °C | Slow cooling (furnace or insulated) | Near-net shape, refined grain flow |
| Soft annealing (+A) | 680-720 °C | Slow furnace cooling | ≤ 241 HB, best machinability |
| Normalizing (+N) | 840-880 °C | Air | Uniform, refined structure |
| Hardening | 820-860 °C | Oil or water/polymer quench | Martensitic structure |
| Tempering (+QT) | 540-680 °C | Air | Sets final strength and toughness |
| Stress relieving | 30-50 °C below last tempering temperature | Slow cooling | Reduces machining and welding stresses |
42CrMo4V equivalent grades
| Country or standard | Designation |
|---|---|
| Europe (EN 10083-3) | 42CrMo4, 1.7225 (+QT = 42CrMo4V) |
| International (ISO 683-2) | 42CrMo4 |
| USA (AISI/SAE, UNS) | AISI 4140, 4142; UNS G41400, G41420; 4140H |
| Japan (JIS G4053) | SCM440 |
| China (GB/T 3077) | 42CrMo |
| UK (BS 970) | 708M40, 709M40 |
| France (AFNOR) | 42CD4 |
| Free-machining variant | 42CrMoS4, 1.7227 |
These grades are close but not identical; for example, AISI 4140 allows 0.38-0.43 % C and 0.75-1.00 % Mn. Name the governing standard on your order.
Applications of 42CrMo4V forgings
- Pumps and compressors
- Rolled rings and shafts for chemical pumps, plunger pumps, gas compressors and industrial air compressors.
- Pressure equipment
- Flanges, tube sheets, nozzles and hollow forgings for pressure vessels, air receivers, shell-and-tube heat exchangers, columns, towers, tanks, silos and preheaters.
- Oil and gas
- Discs, bushings, sleeves and valve parts for subsea and deepwater production systems, wellheads and Christmas trees.
- Valves
- Stems, seat rings, blocks and bodies for ball, gate, globe, check and plug valves, and strainers.
- Power transmission
- Gears, spindles, forged rings and shafts for gearboxes, turbines and power generators.
- Mills and heavy machinery
- Crankshafts, eccentric shafts, rolls and wheels for cement mills, sugar mills, concrete mixers, shipbuilding, and paper and pulp machinery.
How we produce and test 42CrMo4V forgings
- Melting: EAF + LF + VDElectric arc furnace melting, ladle refining and vacuum degassing lower hydrogen and non-metallic inclusions before casting.
- Open-die forging or ring rollingHot working to near-net shape closes internal porosity and gives a grain flow that follows the part's contour.
- Heat treatmentAnnealed, normalized, or quenched and tempered to the strength or hardness on the drawing.
- Ultrasonic testingTo EN 10228-3, SEP 1921 or ASTM A388, with the acceptance class agreed with the customer.
- CertificationEN 10204 3.1 inspection certificate, or 3.2 with a third-party inspector, reporting heat chemistry and mechanical test results.
How to order 42CrMo4V forgings
Send us the following and we will quote:
- Drawing, or finished and forged dimensions with machining allowance
- Quantity
- Delivery condition (annealed, normalized or +QT) and target strength or hardness
- Governing standard or customer specification
- Ultrasonic testing standard and acceptance class
- Certificate type (EN 10204 3.1 or 3.2, and the inspection agency if 3.2)
42CrMo4V frequently asked questions
What is 42CrMo4V steel?
42CrMo4V is 42CrMo4 (1.7225) chromium-molybdenum alloy steel in the quenched and tempered condition. The V stands for the German word vergütet. In EN 10083-3 the same material is designated 42CrMo4+QT. It is used for highly stressed forged parts such as shafts, gears, rolled rings and flanges.
Does the V in 42CrMo4V mean vanadium?
No. The V refers to the quenched and tempered (vergütet) delivery condition, not to a vanadium addition. The chemical composition is the same as standard 42CrMo4: 0.38-0.45 % C, 0.90-1.20 % Cr and 0.15-0.30 % Mo.
What is the AISI equivalent of 42CrMo4V?
The closest American grades are AISI/SAE 4140 and 4142 (UNS G41400 and G41420). Other close equivalents are JIS SCM440, GB 42CrMo, BS 708M40 and AFNOR 42CD4. Chemistry limits differ slightly between standards, so the governing standard should be named on the order.
What tensile strength does 42CrMo4V have?
Under EN 10083-3, quenched and tempered 42CrMo4 reaches 1100-1300 MPa tensile strength in sections up to 16 mm, 1000-1200 MPa up to 40 mm, 900-1100 MPa up to 100 mm, 800-950 MPa up to 160 mm and 750-900 MPa up to 250 mm. Larger forgings are tested to values agreed at the order stage.
Which 42CrMo4V forgings does Jiangyin Jiangnan Metal produce?
Jiangyin Jiangnan Metal Co., Ltd. produces 42CrMo4V seamless rolled rings, forged rings, shafts, eccentric shafts, flanges, tube sheets, discs, bushings, sleeves, round bars, hollow forgings, gears and valve components, all made to the customer's drawing or size.
What testing and certificates come with 42CrMo4V forgings?
42CrMo4V forgings from Jiangyin Jiangnan Metal can be ultrasonically tested to EN 10228-3, SEP 1921 or ASTM A388. The company supplies EN 10204 3.1 inspection certificates, or 3.2 certificates witnessed by a third-party inspector on request.
Can 42CrMo4V be welded?
Yes, but it needs care. Because of its carbon and alloy content, 42CrMo4 is prone to hydrogen cracking, so welding normally needs preheating to about 200-300 °C, low-hydrogen consumables and a post-weld stress relief. Where possible, avoid welding in highly stressed areas.
How do I get a price for 42CrMo4V forgings?
Send the drawing or finished dimensions, quantity, delivery condition, required mechanical properties and inspection standard to sales@steelforgepieces.com or call +86 189 2135 9659. Jiangyin Jiangnan Metal will reply with a quotation.
About the supplier
Jiangyin Jiangnan Metal Co., Ltd. is an open-die forging factory in Zhouzhuang Town, Jiangyin City, Jiangsu Province, China. The company forges carbon steel, alloy steel, tool steel, stainless steel and nickel alloys into rings, shafts, flanges, discs and bars to customer drawings for customers worldwide.
Jiangyin Jiangnan Metal Co., Ltd.No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China
Phone: +86 189 2135 9659
Email: sales@steelforgepieces.com
Web: www.steelforgepieces.com
Data on this page follows EN 10083-3 and EN 10250-3. Inspection and certification to EN 10228-3, SEP 1921, ASTM A388 and EN 10204. Page updated 11 September 2026.