40NiCrMo6 Alloy Structural Steel
40NiCrMo6 alloy structural steel is a high-strength nickel-chromium-molybdenum steel with excellent quenchability, high toughness, fatigue resistance, and reliable impact performance. After quenching and tempering, it delivers a strong balance of strength and ductility, making it ideal for gears, shafts, crankshafts, connecting rods, and other critical mechanical components exposed to heavy loads and demanding working conditions.
Product Description
Xiri Tool Steel is a leading supplier of 40NiCrMo6 alloy structural steel in China. 40NiCrMo6 is a type of high-strength nickel-chromium-molybdenum alloy structural steel, corresponding to the German DIN standard designation 1.6565. It is renowned for its excellent quenchability, high toughness, and good impact resistance. After quenching and tempering treatment, this steel exhibits a perfect combination of high strength and good ductility, and is widely used in the manufacture of key mechanical parts such as gears, shafts, crankshafts, and connecting rods that bear high loads.
Whether you need 40NiCrMo6 flat bars, steel plates, or forged rounds, we provide custom dimensions with machining or grinding services. Our materials are strictly tested to ensure premium metallurgical structure.
40NiCrMo6 (per standard EN 10083-3) is a medium-carbon, quenched and tempered nickel-chromium-molybdenum alloy steel. Its very designation reveals its core alloying elements: nickel (Ni), chromium (Cr), and molybdenum (Mo). The optimal ratio of these three elements collectively endows it with exceptional properties surpassing ordinary steels.
Chemical Composition of 40NiCrMo6 steel
| C | Si | Mn | Cr | P | S | Ni | Mo |
| 0.37-0.45 | 0.15-0.35 | 0.50-0.90 | 0.60-1.00 | ≤0.035 | ≤0.025 | 1.60-2.00 | 0.15-0.30 |
Supply Form & Size Range of 40NiCrMo6 steel
We supply 40NiCrMo6 steel in various forms to meet your manufacturing needs:
Round bar: Diameter 16mm – 1000mm
Steel Plate / Flat: Thickness 16mm – 1000mm x Width 200mm – 1800mm
Surface: Black, Peeled, Rough machined or Grinded.
Delivery Condition: Annealed or QT.
Core Performance of 40NiCrMo6 Alloy Structural Steel
-
Unparalleled Combination of Strength and Toughness
This stands as 40NiCrMo6’s most distinguished characteristic. It not only withstands exceptionally high static and dynamic loads but also effectively absorbs impact energy, preventing catastrophic brittle fracture during unexpected overloads. This ensures your equipment—whether heavy-duty gears in excavators or critical shafts in wind turbines—remains stable under harsh conditions, significantly extending service life and minimising substantial losses from unplanned downtime.
-
Exceptional Fatigue Strength
Under alternating loads, a material’s resistance to fatigue crack initiation and propagation is paramount. 40NiCrMo6’s refined microstructure and high strength confer an exceptionally high fatigue limit, making it particularly suited for manufacturing critical components subjected to cyclic stresses—such as crankshafts, connecting rods, and gears—imbuing your products with a ‘longevity gene’.
-
Outstanding Quenchability
Quenchability determines the uniformity of cross-sectional properties after heat treatment. 40NiCrMo6’s exceptional quenchability ensures consistent mechanical properties from surface to core, even in large cross-sections. This eliminates potential failure risks from performance gradients, instilling greater confidence when designing large, thick-walled components.
-
Excellent Machinability and Heat Treatment Adaptability
In the annealed condition, 40NiCrMo6 exhibits excellent machinability, facilitating turning, milling, drilling, and other mechanical processing. Simultaneously, it responds sensitively to various heat treatment processes. Through precise control, a broad performance spectrum from high strength to high toughness can be achieved, meeting your diverse design requirements.
Application Fields of 40NiCrMo6 Alloy Structural Steel | Witnessing the Limitless Potential of an Exceptional Material
The outstanding properties of 40NiCrMo6 enable it to play a pivotal role in numerous demanding industrial sectors:
Automotive and Rail Transport: Critical safety components including engine crankshafts, connecting rods, transmission gears, drive shafts, and coupler hooks.
Heavy Machinery and Engineering Equipment: Rotary bearings, drive gears, and high-pressure hydraulic cylinder rods for excavators and cranes.
Energy and Power Generation: Main shafts for wind turbines, gearbox components, and rotor parts for gas turbines and steam turbines.
Aerospace and Defence: Landing gear components, missile casings, high-performance gears and shafts.
Moulding and Precision Manufacturing: Large plastic moulds, die-casting mould frames, high-strength lead screws and precision shafts.
In short, any application prioritising safety, reliability and extended service life provides the perfect stage for 40NiCrMo6 to excel.
Our Advantages in Processing 40NiCrMo6 Alloy Structural Steel
Fully appreciating your zero-tolerance stance on quality, we firmly believe exceptional material performance must be underpinned by an infallible quality assurance system. Within our production process, ‘quality’ is not merely inspected into existence—it is cast into the very DNA of every stage.
-
Source Control: Refining Pure Molten Steel
We employ advanced Electric Arc Furnace (EAF) smelting, followed by LF ladle refining and VD/VOD vacuum degassing. This process significantly reduces harmful gases (oxygen, hydrogen) and inclusions in the molten steel, ensuring material purity, density, and fatigue resistance from the outset.
-
Precision Forming: Controlled Rolling, Controlled Cooling and Precision Forging
We apply controlled rolling and controlled cooling techniques to precisely regulate temperature and deformation during forging or rolling, optimising the material’s grain structure. For complex-shaped components, precision forging is employed. This not only minimises material wastage but also establishes continuous, rational fibre flow lines, maximising the product’s mechanical properties.
-
Core Essence: Digitalised Heat Treatment Process
Heat treatment is the pivotal step activating the ‘soul’ of 40NiCrMo6’s performance. Our computer-controlled continuous quenching and tempering line ensures millimetre-precise control over quenching temperature, duration, cooling medium, and tempering curves. Every batch is accompanied by comprehensive heat treatment traceability records, guaranteeing uniform, stable, and reproducible performance.
-
End-to-End Verification: Comprehensive Inspection System
From raw materials to finished products, we implement rigorous testing protocols:
Chemical Composition Analysis: Direct-reading spectrometers guarantee precise compliance with specifications.
Mechanical Properties Testing: Universal testing machines and impact testers deliver accurate strength, elongation, and impact energy data.
Metallographic Analysis: Electron microscopes examine microstructures to determine grain size and banding levels.
Non-Destructive Testing: Ultrasonic Testing (UT) and Magnetic Particle Testing (MT) guarantee internal and surface defect-free conditions.
Dimensional Accuracy Inspection: Precision tools such as coordinate measuring machines ensure dimensions fully comply with drawing specifications.
Not sure about the best equivalent for your application?
Why Manufacturers Choose Huangshi Xiri
Huangshi Xiri combines international-standard steel grades, a complete tool steel portfolio, strict quality control and reliable global supply. We match DIN / JIS / AISI equivalents precisely, offer cutting and heat-treatment services, and control every step from smelting to inspection. With stable capacity, on-time delivery and responsive technical support, we help manufacturers reduce risk, save costs and run production with confidence.
Contact Us
Contact Huangshi Xiri today for quotations, grade selection and technical support on tool steel, mold steel and alloy steel. Whether you need samples, cutting-to-size service or long-term supply for your projects, our engineers and sales team are ready to respond quickly with professional advice and reliable solutions for your manufacturing needs.
