Ductile Cast Iron Square Bar
Ductile cast iron square bar is produced from nodular iron with spherical graphite, which resists crack propagation better than flake graphite in gray iron. This makes it suitable for load-bearing, vibration-resistant, and fatigue-prone applications where strength and toughness matter. Jialu supplies ductile iron square bar across multiple international standards—GB, JIS, KS, AWS and UNS—so a project requiring QT600-
- Spherical graphite structure resists crack initiation and propagation, improving fatigue and impact resistance
- Available in multiple international standards—GB, JIS, KS, AWS and UNS—on a single stock list
- Custom sizes accepted, so no need to modify design or accept off-size stock
- One supplier for mixed-standard ductile iron scope, 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 square bar is produced from nodular iron with spherical graphite, which resists crack propagation better than flake graphite in gray iron. This makes it suitable for load-bearing, vibration-resistant, and fatigue-prone applications where strength and toughness matter. Jialu supplies ductile iron square bar across multiple international standards—GB, JIS, KS, AWS and UNS—so a project requiring QT600-3 for a pump housing, FCD500-7 for a gear housing, or GCD450 for a machine base can be sourced on one contract, one inspection and one shipment. Custom sizes are available to match exact machining or assembly needs.
Why Buyers Choose It
- Spherical graphite structure resists crack initiation and propagation, improving fatigue and impact resistance
- Available in multiple international standards—GB, JIS, KS, AWS and UNS—on a single stock list
- Custom sizes accepted, so no need to modify design or accept off-size stock
- One supplier for mixed-standard ductile iron scope, reducing inspection and shipment complexity
- Supports heavy-duty structural, mechanical and wear-resistant applications with consistent performance
Where It Is Used
- Machine base plates and frame components in industrial equipment requiring high rigidity and vibration damping
- Pump and valve housings where fatigue resistance and pressure integrity are critical
- Gear housings and transmission components exposed to cyclic loading and shock
- Foundry patterns and tooling inserts where dimensional stability and wear resistance are required
- Heavy-duty brackets, supports and structural members in mining, construction and material handling equipment
- Custom machined parts for agricultural machinery, marine systems, and offshore platforms
Who It Is For
- Machine builders sourcing structural and mechanical components with mixed-grade ductile iron requirements
- Foundries and fabricators needing consistent nodular iron supply for casting or machining operations
- EPC contractors managing mechanical packages with multiple ductile iron callouts across different standards
- Equipment manufacturers requiring fatigue-resistant parts for high-cycle or high-vibration service
Problems It Solves
- Splitting ductile iron scope across multiple foundries or mills, which increases inspection points and shipment dates
- Inconsistent material grades when one mill cannot supply a specific standard like FCD600-3 or GCD500
- Design delays due to unavailable sizes or non-standard grades that require custom casting
- Multiple purchase orders and inspection certificates for the same project when standards vary across components
- Late substitutions when a grade is not available in the required size or standard
Technical Features
- Spheroidal graphite structure achieved through magnesium treatment during melt processing
- Tensile strength from 400 MPa to 900 MPa, depending on grade and heat treatment
- Ductility from 10% to 18% elongation, enabling deformation without fracture
- Available in standard grades: GB QT400-15 to QT900-2, JIS FCD350-22 to FCD800-2, KS GCD370 to GCD800, AWS 60-40-18 to 120-90-02, UNS F32800 to F36200
- Heat treatment options available to enhance strength or ductility, as required by the application
- Custom sizes produced to exact dimensions, including tolerance and surface finish
- Suitable for machining, welding (with preheat and post-weld heat treatment), and surface treatments
Grades Standards And Size Range
Values below come from the published product data. Anything not listed is confirmed per enquiry.
| GB Grades | QT400-15, QT400-18, QT450-10, QT500-7, QT600-3, QT700-2, QT800-2, QT900-2 |
|---|---|
| JIS Grades | FCD350-22, FCD400-18, FCD400-15, FCD450-10, FCD500-7, FCD600-3, FCD700-2, FCD800-2 |
| KS Grades | GCD370, GCD400, GCD450, GCD500, GCD600, GCD700, GCD800 |
| AWS Grades | 60-40-18, 65-45-12, 80-55-06, 100-70-03, 120-90-02 |
| UNS Grades | F32800, F33100, F33800, F34800, F36200 |
| Section Shape | Square |
| Size | Customized |
| Tolerance | Standard machining tolerance available; custom tolerance on request |
| Surface Finish | As-cast or machined, depending on order specification |
| Heat Treatment | Available on request to improve strength or ductility |
Materials
- Ductile cast iron with spherical graphite for improved toughness and fatigue resistance
- High-strength grades like QT800-2 and FCD800-2 for heavy-duty structural and mechanical use
- Medium-strength grades like QT500-7 and FCD500-7 for general mechanical components
- Low-strength grades like QT400-15 and FCD350-22 for non-critical load-bearing parts
- Custom alloyed ductile iron available for specific wear or temperature performance
Manufacturing Route
Quality Control
- Chemical composition verified against the ordered grade using spectrometric analysis
- Mechanical properties tested per standard—tensile strength, elongation and hardness
- In-house CNAS-certified laboratory conducts routine testing and holds traceable records
- Third-party inspection available on request, with scheduling at order stage
- Mill certificates issued per purchase order, including grade, standard, test results and batch number
Customisation Options
- Custom sizes and tolerances available to match machining or assembly requirements
- Grade selection per component, so one order can mix GB, JIS and AWS callouts
- Surface finish and marking arranged per destination or inspection regime
- OEM service accepted for branded or private-label delivery
- Packaging tailored to shipment method—ocean, rail, air or land freight
How It Compares With The Alternatives
| Gray cast iron square bar | Ductile iron has higher tensile strength and ductility; gray iron is cheaper but brittle and prone to cracking under impact or fatigue |
|---|---|
| Wrought steel square bar | Steel offers higher strength and uniformity; ductile iron is more vibration-damping and cost-effective for complex shapes and high-volume castings |
| Alloy steel square bar | Alloy steel has higher strength and heat resistance; ductile iron is more economical for moderate-stress applications with good wear and fatigue performance |
Buying Guide
- Start with the required mechanical properties—tensile strength and elongation—then select the grade family
- For high-vibration or cyclic loading, choose grades with higher ductility like QT600-3 or FCD600-3
- For wear resistance, consider higher-strength grades like QT800-2 or FCD800-2, or specify surface hardening
- Send the size and tolerance requirements with the enquiry, as availability varies by section and length
- Specify the standard (GB, JIS, AWS, etc.) to ensure compliance with local code or procurement rules
Questions About Ductile Cast Iron Square Bar
Which ductile iron standards do you supply?
We supply GB, JIS, KS, AWS and UNS standards, including QT400-15 to QT900-2, FCD350-22 to FCD800-2, GCD370 to GCD800, 60-40-18 to 120-90-02, and F32800 to F36200.
Can one order include multiple grades and standards?
Yes. Mixed-grade and mixed-standard ductile iron square bar is standard here—buyers consolidate their scope with us to avoid splitting across mills.
Do you offer custom sizes?
Yes. Custom sizes are available to match exact machining or assembly needs.
What certifications do you hold?
We hold 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 align with production schedule.
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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