4Cr5MoSiV Hot Work Tool Steel

4Cr5MoSiV Hot Work Tool Steel is a reliable and widely used hot work die steel, particularly effective in applications involving elevated temperatures. At Aobo Steel, with over 20 years of forging experience, we understand the demands placed on tool steels like 4Cr5MoSiV and can provide the quality and technical support you need. This steel offers a solid combination of properties for demanding tooling.

1. Understanding Grade Designations

You may encounter various names for steels similar to 4Cr5MoSiV. For instance, the Chinese standard 4Cr5MoSiV1 (note the ‘1’) is sometimes used interchangeably in the market with industry standards like SM4Cr5MoSiV1 or even international grades like H13 (AISI) and SKD61 (JIS). While these grades are closely related and often comparable, there can be slight differences, particularly in thermal strength where 4Cr5MoSiV1 generally offers higher performance. We focus here on 4Cr5MoSiV, but understanding these related grades is important. Aobo Steel can help clarify the specific grade best suited for your requirements.

2.  4Cr5MoSiV Tool Steel Chemical composition

• Carbon (C): 0.33～0.43%
• Silicon (Si): 0.80～1.20%
• Manganese (Mn): 0.20～0.50%
• Phosphorus (P): ≤0.030%
• Sulfur (S): ≤0.030%
• Chromium (Cr): 4.75～5.50%
• Molybdenum (Mo): 1.10～1.60%
• Vanadium (V): 0.30～0.60%

3. Key Properties of 4Cr5MoSiV Tool Steel

This grade is classified as a medium heat-resistant hot work die steel. Its key advantages include:

• Good Thermal Strength: Performs well at medium temperatures, maintaining strength up to approximately 600°C.
• Thermal Fatigue Resistance: Withstands the stresses of repeated heating and cooling cycles common in hot work applications.
• Wear Resistance: Offers dependable resistance against wear.
• Excellent Hardenability: As an air-hardening steel, it can be effectively hardened by air cooling from the austenitizing temperature. This simplifies the heat treatment process and significantly reduces the risk of distortion and cracking compared to water or oil quenching.
• Reduced Scaling: Shows less tendency to form oxide scale during heat treatment.
• Molten Aluminum Resistance: Resists erosion from molten aluminum, making it ideal for specific die-casting applications.

4. 4Cr5MoSiV Tool Steel Applications

Thanks to its balanced properties, 4Cr5MoSiV is a versatile choice for various tooling needs:

• Die-Casting Molds: Especially suitable for aluminum alloys.
• Hot Extrusion Tooling: Used for dies and mandrels (cores).
• Forging Dies: Employed in dies for die-forging hammers, forging presses, and as inserts for precision forging.
• Plastic Molds: Suitable for certain demanding plastic molding applications.
• High-Temperature Components: Occasionally used for structural parts that operate at elevated temperatures.

5. 4Cr5MoSiV Tool Steel Heat Treatment Guidelines

Proper heat treatment is critical to achieving the desired performance from 4Cr5MoSiV. While specific parameters should be tailored to the application, typical ranges are:

• Annealing: Heat to 860-890°C, hold for 2-4 hours, then cool the furnace slowly to below 500°C. Finally, air cool. Expected hardness: ≤229 HBW.
• Hardening (Quenching): Heat to 1000-1030°C, then cool in air or oil. Expected hardness: 53-55 HRC.
• Tempering: Temper at 530-580°C, air cool. Tempering is often performed twice to refine the structure. Expected final hardness: 47-49 HRC.

Important Note: Controlling cooling rates during heat treatment is essential to prevent cracking. Aobo Steel has extensive experience and can provide guidance on optimizing heat treatment for your specific tools.

6. Additional Considerations

6.1 Material Quality Options

For applications demanding superior cleanliness, homogeneity, and mechanical properties, Electro-Slag Remelted (ESR) versions of similar grades (like H13/4Cr5MoSiV1) are available. While ESR processing increases cost, it can significantly enhance tool life and performance in critical applications.

6.2 Surface Treatments

4Cr5MoSiV responds well to surface treatments like nitriding. Nitriding significantly increases surface hardness, improving wear resistance and corrosion resistance, which is highly beneficial for extending the life of die-casting and extrusion molds. Other co-nitriding processes (O-S-N, S-N-C, B-N-C) can also be applied for specific performance enhancements.

Your Partner for 4Cr5MoSiV Steel

4Cr5MoSiV provides a reliable and cost-effective solution for many hot work tooling challenges. At Aobo Steel, we combine our deep knowledge of tool steel metallurgy with over two decades of forging expertise and strong relationships with over 40 suppliers to deliver quality materials like 4Cr5MoSiV. We focus on providing solutions. Contact us to discuss your specific requirements for 4Cr5MoSiV or other tool and alloy steels.