D4512 Ductile Iron: Composition, Applications, Market Trends 2025

D4512, also known as SAE J434 D4512, is a grade of ductile cast iron characterized by its ferritic microstructure. This grade is commonly used in applications requiring moderate strength and excellent machinability. It is a part of the SAE J434 series, which includes various grades of ductile iron suitable for different engineering applications.

1. Chemical Composition and Mechanical Properties

The chemical composition of D4512 typically includes:

• Carbon (C): 3.4–3.8%

• Silicon (Si): 2.5–3.0%

• Manganese (Mn): 0.3–0.6%

• Magnesium (Mg): 0.03–0.05%

• Phosphorus (P): ≤0.04%

• Sulfur (S): ≤0.02%

Mechanical properties include:

• Tensile Strength: Approximately 450 MPa

• Yield Strength: Approximately 300 MPa

• Elongation: ≥12%

• Hardness: Typically around 180–220 HB

2. Equivalent Grades in Global Standards

D4512 corresponds to several equivalent grades in international standards:

• ASTM A536: Grade 65-45-12

• ISO 1083: Grade 400-12

• DIN: GGG40

• EN: EN-JS400-12

These equivalents ensure that D4512 can be used interchangeably in various global markets, provided that the mechanical properties align with the requirements.

3. Manufacturing Processes and Heat Treatment

D4512 is typically produced using sand casting or centrifugal casting methods. The casting process involves pouring molten iron into molds to form the desired shape. Heat treatment processes, such as annealing, can be applied to enhance specific properties like strength and hardness.

The microstructure consists primarily of ferrite with small amounts of pearlite, contributing to its excellent machinability and moderate strength.

4. Applications in Various Industries

D4512 ductile iron is utilized in industries where moderate strength and high machinability are required. Applications include:

• Automotive: Engine components, suspension parts

• Agricultural Machinery: Gearboxes, housings

• Industrial Equipment: Pumps, valves

• Construction: Structural components

Its combination of properties makes it suitable for components subjected to moderate stress and requiring precise machining.

5. Market Pricing Trends and Factors

The price of D4512 ductile iron varies based on factors such as raw material costs, production methods, and market demand. As of recent data, the price for rough castings ranges between $1,300 and $1,600 per ton.

Additional costs may arise from machining, heat treatment, and surface finishing processes. Market fluctuations in raw material prices, particularly for iron and alloying elements, can significantly impact the overall cost.

6. Comparison with Other Ductile Iron Grades

This comparison highlights the suitability of each grade for specific applications based on their mechanical properties.

7. Advantages and Limitations

Advantages:

• Excellent Machinability: Due to its ferritic structure.

• Moderate Strength: Suitable for components under moderate stress.

• Good Ductility: Offers resistance to impact and shock loading.

Limitations:

• Lower Strength Compared to Other Grades: Not suitable for high-stress applications.

• Sensitive to Heat Treatment: Improper heat treatment can affect mechanical properties.

8. FAQs

Q1: What is the primary advantage of using D4512 ductile iron?

D4512 offers a balance between machinability and strength, making it ideal for components that require precise machining and are subjected to moderate stress.

Q2: How does D4512 compare to other ductile iron grades?

Compared to grades like D550 or D700, D4512 has lower tensile strength but offers superior machinability, making it suitable for components where ease of machining is a priority.

Q3: What industries commonly use D4512 ductile iron?

Industries such as automotive, agriculture, and industrial equipment manufacturing utilize D4512 for components like engine parts, gearboxes, and housings.

Q4: What factors influence the pricing of D4512 ductile iron?

Raw material costs, production methods, and market demand are primary factors affecting the price of D4512. Additionally, costs for machining and heat treatment can influence the overall price.

Q5: Can D4512 be heat treated to improve its properties?

Yes, heat treatment processes like annealing can enhance specific properties of D4512, such as strength and hardness, to meet application requirements.

Q6: Are there alternative materials to D4512 for similar applications?

Yes, materials like ASTM A36 carbon steel or other ductile iron grades such as D550 or D700 may be considered, depending on the specific requirements of strength, machinability, and cost.

9. Conclusion

D4512 ductile iron is a versatile material offering a combination of moderate strength and excellent machinability, making it suitable for a wide range of applications. Understanding its properties, equivalents, and market factors is essential for engineers and procurement professionals when selecting materials for specific components.

References:

• Ductile Iron – Wikipedia
• ASTM A536: Standard Specification for Ductile Iron Castings
• ISO 1083: Ductile Iron Castings
• DIN Standards – German Institute for Standardization
• JIS Standards – Japanese Industrial Standards Committee