Xi'an Dongmeng Group Co., Ltd. is one of the most reliable manufacturers and suppliers of 15CrNi4Mo Alloy Steel Forgings Supplier in China, also supports customized service. With abundant experience, we warmly welcome you to wholesale cheap products in stock here and get free sample from our factory. For price consultation, contact us.
15CrNi4Mo Alloy Steel Forgings
High-Toughness Case-Hardening Steel for Large Gears, Shafts and Transmission Components
Xi'an Dongmeng Group Co., Ltd. supplies 15CrNi4Mo nickel-chromium-molybdenum alloy steel forgings for heavy-duty transmission components requiring a hard, wear-resistant carburized surface and a strong, impact-resistant core.
Available products include forged bars, gear blanks, rings, shafts, blocks and rough-machined components manufactured according to drawings and project specifications.
Product Forms: Forged Bar · Gear Blank · Ring · Shaft · Block
Delivery Conditions: Forged · Annealed · Normalized · Rough Machined
Processing: Forging · Heat Treatment · Turning · Drilling · UT
Documents: MTC 3.1 · Inspection Report · Heat Treatment Record
Applications: Large Gears · Pinions · Gear Shafts · Heavy Transmissions
Request 15CrNi4Mo Steel Quote
Send Drawing for Technical Review
What Is 15CrNi4Mo Alloy Steel?
15CrNi4Mo is a low-carbon nickel-chromium-molybdenum alloy steel intended primarily for carburized and case-hardened components.
The low-carbon core supports toughness and resistance to impact loading. Nickel contributes to core toughness and through-section strength, while chromium and molybdenum improve hardenability and heat-treatment response.
After the appropriate carburizing and heat-treatment process, the material can develop:
A hard, wear-resistant outer case
A comparatively tough and ductile core
Improved resistance to tooth-root impact
Good performance under repeated contact loading
More stable properties in larger component sections
The final properties are controlled not only by the steel grade but also by forging reduction, section size, carburized case depth, quenching method, tempering process and machining allowance.
Important Grade Identification
15CrNi4Mo should be ordered by its full material designation and governing standard.
It should not automatically be described as equivalent to EX30, 15CrNiMo, 18CrNiMo7-6, 17CrNiMo6, 835M15 or other international carburizing grades.
Materials from different standards may have differences in:
Nickel content
Chromium and molybdenum ranges
Cleanliness requirements
Grain-size control
Hardenability
Mechanical testing
Heat-treatment condition
Permitted residual elements
Ultrasonic-testing acceptance level
Cross-reference information may be used for preliminary material selection, but final substitution must be approved according to the chemical composition, mechanical properties, component dimensions and design specification.
Available Product Forms
Forged Round Bar
Suitable for machining large shafts, pinions, couplings and cylindrical transmission components.
Available conditions may include:
Black forged surface
Shot-blasted surface
Rough turned
Peeled or machined
Annealed
Normalized
High-temperature tempered
Gear Blanks
Custom-forged gear blanks can be supplied according to the required outside diameter, bore, thickness, machining allowance and forging ratio.
Available forms include:
Solid gear blanks
Bored gear blanks
Hub-type gear blanks
Flanged gear blanks
Disc forgings
Pinion blanks
Shaft Forgings
Custom shafts can be manufactured with stepped diameters, flanges, shoulders and machining allowances.
Typical products include:
Gear shafts
Pinion shafts
Transmission shafts
Drive shafts
Reducer shafts
Heavy-equipment shafts
Ring Forgings
Rolled or open-die forged rings can be supplied for large ring gears, bearing components and transmission assemblies.
Forged Blocks
Rectangular or square forged blocks are available for machining custom high-load components.
Recommended Supply Range
The following range should be adjusted to match actual production and stock capability before publication.
| Product Form | Recommended Published Range |
| Forged Round Bar | Custom diameter and length |
| Gear Blank | Manufactured according to drawing |
| Shaft Forging | Stepped or straight shaft according to drawing |
| Ring Forging | Custom OD, ID and height |
| Forged Block | Custom width, thickness and length |
| Unit Weight | Confirm according to forging capability |
| Machining Allowance | Agreed according to drawing |
| Surface | Black, shot blasted or rough machined |
| Delivery Condition | Forged, annealed, normalized or agreed condition |
For accurate feasibility review, provide a drawing showing the finished dimensions, forging dimensions, test location and required heat-treatment condition.
Chemical Composition Control
The chemical composition must comply with the governing standard or a customer-approved material specification.
Each heat should be verified using an appropriate chemical-analysis method, and the heat-specific values should be recorded on the mill test certificate.
Particular attention should be paid to:
Carbon control for carburizing response and core toughness
Nickel content for large-section core properties
Chromium and molybdenum for hardenability
Phosphorus and sulfur limits
Residual-element control
Aluminum and grain-refining practice where specified
Hydrogen, oxygen and nitrogen control for critical forgings
Published chemical-composition values should not be copied from unrelated carburizing steel grades.
For critical gears or large-section forgings, the purchaser may specify additional requirements for vacuum degassing, electroslag remelting, cleanliness or restricted residual elements.
Mechanical Properties
Mechanical properties for 15CrNi4Mo cannot be represented by one universal tensile-strength or hardness value.
The test result depends on:
Forging section size
Sampling position and orientation
Heat-treatment condition
Carburized or non-carburized test condition
Core hardness requirement
Effective case depth
Quenching method
Final tempering temperature
Applicable material standard
The purchase order should clearly distinguish between:
Raw-material delivery hardness
Core mechanical properties
Surface hardness after carburizing
Effective case depth
Total case depth
Tooth-root or finished-component hardness
Test coupon and test location
Surface hardness alone does not demonstrate adequate core toughness or correct carburized case depth.
Carburizing and Heat Treatment
A typical production route for 15CrNi4Mo components may include:
Steelmaking and ingot or billet preparation
Forging with controlled reduction
Preliminary heat treatment
Rough machining
Ultrasonic inspection
Stress relief where required
Carburizing
Diffusion treatment
Quenching
Low-temperature tempering
Finish machining or grinding
Final hardness and case-depth inspection
The actual carburizing temperature, holding time, carbon potential, quenching temperature and tempering cycle must be developed according to the component dimensions and required case depth.
Heat-Treatment Information Required
Please provide:
Finished component dimensions
Carburized areas
Areas to remain soft
Required surface hardness
Effective case depth
Core hardness
Distortion allowance
Grinding allowance
Permitted retained austenite
Carbide-distribution requirement
Applicable inspection standard
Heat treatment should not be selected solely from a generic online temperature table.
Why Use 15CrNi4Mo for Large Gear Components?
Tough Core
The nickel-alloyed core is intended to retain toughness under shock, bending and cyclic transmission loads.
Hardenable Large Sections
Chromium, nickel and molybdenum support hardenability and help achieve more consistent core properties in larger forged components.
Wear-Resistant Case
Carburizing and hardening produce a surface suitable for gear teeth and contact areas exposed to repeated rolling or sliding wear.
Fatigue Performance
Properly controlled forging, carburizing, grinding and surface finishing can support resistance to contact fatigue and tooth-root fatigue.
Custom Forging Capability
The material can be supplied as gear blanks, shafts, rings and other near-net-shape forgings to reduce unnecessary machining.
Actual service performance depends on component design, material cleanliness, forging quality, heat treatment, machining and lubrication.
Typical Applications
15CrNi4Mo alloy steel forgings may be selected for:
Large industrial gears
Heavy-duty pinions
Gear shafts
Transmission shafts
Speed-reducer components
Mining machinery transmissions
Marine drive components
Heavy-equipment gearboxes
Power-transmission assemblies
High-load mechanical components
Custom carburized forgings
Application suitability must be confirmed by the designer or material engineer.
Forging Process Control
Large alloy steel forgings require more than simple shape forming.
Important controls include:
Ingot or billet source
Melting and refining route
Forging temperature
Forging reduction ratio
Deformation uniformity
Grain-flow direction
Cooling after forging
Preliminary heat treatment
Removal of surface defects
Machining allowance
Test-material position
Heat-number traceability
For gear blanks and shafts, the grain-flow direction should be considered together with the component geometry and loading direction.
Photographs of the forging process do not replace documented process control and inspection results.
Machining Services
Custom machining can be arranged according to drawings.
Available operations may include:
Rough turning
Facing
Boring
Drilling
Saw cutting
Milling
Center-hole machining
Step-shaft machining
Gear-blank preparation
Surface grinding
Chamfering
Deburring
Machining tolerances should be agreed separately from forging tolerances.
For heat-treated components, sufficient grinding and distortion allowance should be reserved before carburizing.
Inspection and Quality Assurance
Material Identification
Heat-number verification
MTC review
Chemical-composition analysis
Product and drawing traceability
Marking inspection
Ultrasonic Testing
UT can be arranged to inspect internal discontinuities in forged bars, gear blanks, rings and shaft forgings.
The enquiry should specify:
UT standard
Inspection stage
Scanning surface
Acceptance class
Reference reflector
Untestable zones
Reporting requirements
A statement such as "UT passed" is not sufficient without the applicable test standard and acceptance level.
Mechanical Testing
Depending on the specification:
Tensile test
Yield strength
Elongation
Reduction of area
Impact test
Brinell hardness
Core hardness
Metallurgical Inspection
Optional metallurgical testing includes:
Grain size
Non-metallic inclusions
Macrostructure
Microstructure
Decarburization
Carburized case depth
Carbide distribution
Retained austenite
Surface and core hardness profile
Dimensional Inspection
Outside diameter
Inside diameter
Length
Thickness
Straightness
Concentricity
Machining allowance
Drawing dimensions
Third-Party Inspection
Inspection by SGS, BV, TÜV or another agreed agency can be arranged before shipment.
Inspection Documents
Available documents may include:
EN 10204 3.1 Mill Test Certificate
Chemical-analysis report
Mechanical-test report
Ultrasonic-testing report
Heat-treatment record
Hardness report
Dimensional-inspection report
Metallographic report
Packing list
Certificate of origin
Third-party inspection report
EN 10204 3.2 documentation should only be offered when the required independent validation and inspection arrangements have been confirmed before production.
Packing and Export Delivery
Packaging is designed according to product shape, unit weight, machining condition and unloading method.
Typical packing includes:
Steel frames
Heavy-duty wooden skids
Fumigated wooden cases
Anti-rust oil
Waterproof wrapping
Surface protection
Machined-surface protection
Steel straps
Lifting-point identification
Heat-number marking
Shipping marks
Large gear blanks, rings and shaft forgings should be secured to prevent movement, surface damage and collision during loading and ocean transport.
Why Choose Xi'an Dongmeng Group Co., Ltd.?
Drawing-Based Technical Review
We review the forging dimensions, finished dimensions, material standard, heat treatment and inspection requirements before quotation.
Custom Forging Supply
Forged bars, gear blanks, rings, shafts and blocks can be supplied according to drawings.
Inspection Coordination
UT, mechanical testing, hardness testing, metallography and third-party inspection can be arranged according to the purchase specification.
Machining Support
Rough machining and pre-machining can reduce overseas processing time and transportation of unnecessary material.
Heat-Number Traceability
Material identity and inspection documents can be linked to the supplied heat and product marking.
Export Packing
Customized packing and loading plans are available for heavy and machined forgings.
Information Required for a Quote
Please send:
Material grade
Governing standard
Product form
Forging dimensions
Finished dimensions
Drawing
Unit weight
Quantity
Delivery condition
Heat-treatment requirements
Mechanical properties
Surface hardness
Effective case depth
UT standard and acceptance class
Machining requirements
Inspection-document requirement
Destination port
Frequently Asked Questions
Is 15CrNi4Mo the same as EX30?
The two designations should not be treated as official equivalents without confirmation from the applicable standard, steel mill or heat-specific MTC. Order the material by its full standard and composition requirements.
Is 15CrNi4Mo the same as 18CrNiMo7-6?
No automatic equivalence should be assumed. They may differ in chemical composition, hardenability, mechanical-property requirements and governing standards.
Can you supply 15CrNi4Mo round bar?
The material is primarily suitable for forged bars and custom forgings. Available dimensions and minimum order quantities depend on production route and stock.
Can you manufacture gear blanks?
Yes. Gear blanks can be forged and rough machined according to drawings, machining allowance and inspection requirements.
Can you perform carburizing?
Heat-treatment support may be arranged, but the customer must specify the surface hardness, effective case depth, core hardness, carburized areas and distortion requirements.
What hardness can be achieved?
Final hardness depends on carburizing, quenching, tempering, component size and measurement location. Surface hardness and core hardness must be specified separately.
Is ultrasonic testing available?
Yes. The applicable UT standard, acceptance class, inspection stage and reporting requirements must be stated in the purchase order.
Can you provide an EN 10204 3.1 certificate?
Yes, a heat-specific MTC can be supplied according to the confirmed order and material source.
Can 15CrNi4Mo be welded?
Welding is not normally the preferred manufacturing route for critical carburized gear components. Any welding procedure should be qualified according to the component design, material condition and applicable code.
What should be included in the enquiry?
Send the standard, forging drawing, dimensions, quantity, delivery condition, heat treatment, inspection requirements and destination port.
Contact Us for 15CrNi4Mo Alloy Steel Forgings
Looking for 15CrNi4Mo forged bars, gear blanks, ring forgings, shafts or custom-machined alloy steel components?
Send us your drawing, material specification, dimensions, quantity, heat-treatment requirements and inspection criteria. Our team will review the forging feasibility, machining allowance, testing requirements and export delivery plan before quotation.
Contact Information
Company: Xi'an Dongmeng Group Co., Ltd.
Phone / WhatsApp: +86 157 6921 4734
Email: office@dongmjd.com
Office Address:
Room 4107, Runfeng Building, Sanqiao New Street,
Weiyang District, Xi'an City, Shaanxi Province, China
Hot Tags: 15CrNi4Mo Alloy Steel Forgings Supplier, China 15CrNi4Mo Alloy Steel Forgings Supplier manufacturers, suppliers, factory
