Ductile Cast Iron Round Bar
Ductile cast iron round bar is produced from a nodular graphite matrix, which resists crack propagation and maintains ductility under impact and fatigue loading. This makes it suitable for components that must absorb shock or endure cyclic stress, where a brittle grey iron would fail. Jialu stocks a broad range of ductile iron grades across GB, JIS, KS, AWS and UNS standards, so a project requiring QT600-3 for a pump
- Nodular graphite structure resists crack initiation and propagation, improving fatigue and impact resistance
- Multiple international standards (GB, JIS, KS, AWS, UNS) available on one stock list and one contract
- Custom diameters and lengths available, so bars can be ordered to match machining or assembly needs
- No need to source from separate foundries for different standards, reducing inspection and shipment complexity
Mill certificates issued against the ordered grade and standard. Third-party inspection available on request.
What This Material Is For
Ductile cast iron round bar is produced from a nodular graphite matrix, which resists crack propagation and maintains ductility under impact and fatigue loading. This makes it suitable for components that must absorb shock or endure cyclic stress, where a brittle grey iron would fail. Jialu stocks a broad range of ductile iron grades across GB, JIS, KS, AWS and UNS standards, so a project requiring QT600-3 for a pump housing, FCD600-3 for a gear housing, and GCD500 for a crankshaft does not need to be split across multiple foundries. Custom sizes are available to match the final machining or assembly requirement.
Why Buyers Choose It
- Nodular graphite structure resists crack initiation and propagation, improving fatigue and impact resistance
- Multiple international standards (GB, JIS, KS, AWS, UNS) available on one stock list and one contract
- Custom diameters and lengths available, so bars can be ordered to match machining or assembly needs
- No need to source from separate foundries for different standards, reducing inspection and shipment complexity
- Ductile iron offers higher strength and toughness than grey iron while remaining castable and machinable
Where It Is Used
- Pump housings and impellers in QT600-3 or FCD600-3 where impact and pressure cycling are present
- Gear housings and transmission components in GCD500 or FCD500-7 for moderate load and wear resistance
- Crankshafts and connecting rods in QT800-2 or FCD800-2 where high fatigue strength is required
- Machine tool bases and frames in QT700-2 or FCD700-2 for vibration damping and structural stability
- Valve bodies and fittings in QT400-15 or FCD400-15 for general-purpose service with moderate pressure
- Industrial rollers and shafts in QT500-7 or FCD500-7 where wear and fatigue are key concerns
Who It Is For
- Machine builders sourcing components with mixed international standards on one drawing
- Foundry buyers who need to consolidate multiple grade calls across a single project
- Equipment fabricators requiring ductile iron bars for machining into shafts, housings or structural parts
- Automotive and agricultural machinery suppliers needing fatigue-resistant castings for drivetrain components
Problems It Solves
- Splitting one project across multiple foundries due to differing grade or standard requirements
- Delays caused by waiting for a second foundry to produce a different grade within the project window
- Inconsistent material properties when sourcing from different suppliers for the same component family
- Difficulty in matching a single bar size to multiple machining or assembly steps across different parts
- Lack of availability for custom diameters or lengths in standard stock ranges
Technical Features
- Nodular graphite structure produced through magnesium or cerium inoculation during casting
- Grades available across GB, JIS, KS, AWS and UNS systems, covering tensile strength from 400 MPa to 900 MPa
- Tensile strength and elongation values specified by standard (e.g., QT600-3: 600 MPa min, 3% min elongation)
- Castability and machinability maintained across all grades, suitable for turning, milling and drilling
- Heat treatment available on request to improve hardness or dimensional stability
Grades Standards And Size Range
Values below come from the published product data. Anything not listed is confirmed per enquiry.
| GB standards | QT400-18, QT400-15, QT450-10, QT500-7, QT600-3, QT700-2, QT800-2, QT900-2 |
|---|---|
| JIS standards | FCD350-22, FCD400-18, FCD400-15, FCD450-10, FCD500-7, FCD600-3, FCD700-2, FCD800-2 |
| KS standards | GCD370, GCD400, GCD450, GCD500, GCD600, GCD700, GCD800 |
| AWS standards | 60-40-18, 65-45-12, 80-55-06, 100-70-03, 120-90-02 |
| UNS standards | F32800, F33100, F33800, F34800, F36200 |
| Diameter range | Customized |
| Length range | Customized |
| Tensile strength range | 400 MPa to 900 MPa |
| Production method | Sand casting with nodularization treatment |
Materials
- Ductile cast iron with nodular graphite for improved toughness and fatigue resistance
- GB-standard grades for use in Chinese industrial and infrastructure projects
- JIS-standard grades for Japanese and Asian market applications
- KS-standard grades for South Korean and regional industrial equipment
- AWS and UNS grades for North American and global engineering specifications
Manufacturing Route
Quality Control
- Chemical composition verified against the ordered standard using spectrometric analysis
- Mechanical properties tested for tensile strength, elongation and hardness
- In-house CNAS-certified laboratory performs routine testing
- Third-party inspection available on request before shipment
- Mill certificates issued per purchase order, referencing the standard and grade
Customisation Options
- Custom diameters and lengths available to match machining or assembly requirements
- Grade and standard selected per item, so one order can mix GB, JIS, AWS and UNS callouts
- OEM service accepted for branding and packaging
- Packing and marking arranged to suit destination port and inspection regime
How It Compares With The Alternatives
| Grey cast iron | Ductile iron has higher tensile strength, elongation and impact resistance; grey iron is cheaper but brittle and unsuitable for dynamic or shock-loading applications |
|---|---|
| Steel bar | Ductile iron offers better vibration damping and castability; steel is stronger and more formable but more expensive and harder to machine in complex shapes |
| Wrought iron | Ductile iron is more consistent in composition and mechanical properties; wrought iron is obsolete and not available in modern industrial grades |
Buying Guide
- Start from the required standard (GB, JIS, KS, AWS, UNS) and select the grade based on tensile strength and elongation needs
- For dynamic or impact-loaded components, choose grades with higher elongation (e.g., QT400-18 or FCD400-18)
- For high-stress applications, select higher tensile grades like QT800-2 or FCD800-2
- Specify diameter and length at order stage, as custom sizes require mold setup
- Request third-party inspection at order stage to avoid delays after production
Questions About Ductile Cast Iron Round Bar
Which standards do you supply ductile cast iron round bar in?
GB, JIS, KS, AWS and UNS standards are available, including QT400-18, FCD600-3, GCD500, 60-40-18 and F34800.
Can one order include multiple grades and standards?
Yes. Mixed-grade and mixed-standard orders are standard here, which is why buyers consolidate with us instead of sourcing from multiple foundries.
Are custom diameters and lengths available?
Yes. Custom sizes are available to match machining or assembly requirements.
What certification backs the material?
The company holds ISO 9001, API Q1, PED, CE, API 5L, 5CT and 5DP, with an in-house CNAS-certified laboratory. Mill certificates are issued per order.
Can we appoint our own inspector?
Yes. Third-party inspection is available on request and is best booked at order stage to allow production scheduling.
What payment terms and currencies do you accept?
L/C, T/T, PayPal and credit card, in USD, CAD, AUD, SGD, EUR or RMB.
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