SKD11 Tool Steel Technical Overview

SKD11 tool steel technical overview: SKD11 is a well-established tool steel grade specified under the Japanese JIS standard. We classify it as a high-carbon, high-chromium alloy tool steel, primarily used for cold work applications where high wear resistance and toughness are crucial. Many producers also utilize vacuum degassing during manufacturing to ensure high purity.

1. Key Characteristics and Benefits:

What makes SKD11 a reliable choice? Let’s look at its main properties:

• High Wear Resistance: Achieved through uniformly distributed eutectic carbides in its structure. This translates to longer service life for tools and dies.
• Good Toughness: Offers solid resistance to cracking under stress.
• Excellent Hardenability: Responds well to heat treatment for achieving the desired hardness.
• Dimensional Stability: Exhibits minimal deformation during the quenching process.
• Good Machinability: Thanks to spheroidizing annealing, which softens the steel for easier processing before final hardening.
• Fine Carbide Structure: Features fine and uniform carbide particles.
• High Hardness Potential: Can reach hardness levels above 62 HRC after proper quenching and tempering.
• Improved Fatigue Strength: Modified versions often show enhanced fatigue strength and even better wear resistance than the standard grade.
• Enhanced Toughness Options: Some variations are engineered for improved toughness, further extending die life and minimizing dimensional changes after use. They often achieve≥58 HRC after medium-temperature tempering.

2. Typical Chemical Composition (Weight %):

While exact compositions can vary slightly between manufacturers, here’s a typical range for SKD11:

• Carbon (C): 1.40% % – 1.60%
• Chromium (Cr): 11.00% % – 13.00%
• Molybdenum (Mo): 0.80% – 1.20%
• Vanadium (V): 0.20%- 0.50% (Some variants might have higher V content, up to 0.80%)
• Manganese (Mn): ≤ 0.60%
• Silicon (Si): ≤ 0.40%
• Nickel (Ni): ≤ 0.50%

3. Heat Treatment Guidelines:

Proper heat treatment is critical for SKD11’s performance:

• Austenitizing: Typically performed around 1030°C (sometimes ranging from 1010°C to 1050°C depending on the specific requirements and variant).
• Quenching: Options include air cooling, interrupted salt bath quenching (e.g., 250-500°C), or oil quenching (to ~200°C) followed by air cooling.
• Tempering: Tempering is usually done at 500°C or higher (often double-tempered) for optimal toughness and wear resistance. Hardness peaks are often seen around 500°C tempering. Low-temperature (150-250°C) or specific medium-temperature (480-530°C) tempering cycles are also used for certain applications.
• Nitriding: Surface hardening treatments like gas nitriding (e.g., 525°C for 20-60 hours for ~1250HV) or soft nitriding (e.g., 570°C for 2 hours for ~950HV) can further enhance surface wear resistance.

4. Equivalent Grades Across Standards:

SKD11 is internationally recognized and corresponds to several other standards:

• AISI/ASTM (USA): D2
• GB (China): Cr12Mo1V1
• DIN (Germany): 1.2379 (X155CrVMo121 / X155CrMoV12-1)
• KS (Korea): STD11
• BS (UK): BD2
• NF (France): X160CrMoV12
• ISO: 160CrMoV12
• ASSAB (Sweden): XW-42 / XW41
• HITACHI (Japan): SLD
• DAIDO (Japan): DC11
• NACHI (Japan): CDS11
• BOHLER (Austria): K110

5. Common Applications:

Given its properties, SKD11 is frequently used for:

• Blanking and fine blanking dies
• Cold forging, extrusion, and deep drawing dies
• Punches and hemming dies
• Forming rolls
• Shear blades
• Thread rolling dies
• Cold heading dies
• Wear-resistant components for plastic molds
• Molds for ceramics

6. Comparison Notes:

• Compared to AISI D2, SKD11 generally offers better toughness, although D2 might achieve slightly higher hardness.
• Modified SKD11 grades often aim for an optimized balance between toughness, wear resistance, and machinability.

Important Consideration:

Always refer to the specific material certificate or datasheet provided by the supplier (like us at Aobo Steel) for the precise chemical composition, properties, and heat treatment recommendations for the particular batch of SKD11 you are using. Variations exist, and exact specifications matter for performance.