Bohler-Uddeholm AISI D2 Cold Work Tool Steel

Bohler-Uddeholm AISI D2 Cold Work Tool Steel Product Information -:- For detailed product information, please contact sales. -: Bohler-Uddeholm AISI D2 Cold Work Tool Steel Synonyms -:- For detailed product information, please contact sales. -:

Bohler-Uddeholm AISI D2 Cold Work Tool Steel Product Information -:- For detailed product information, please contact sales. -: # **Böhler-Uddeholm AISI D2 Cold Work Tool Steel** ## **Product Overview** **Böhler-Uddeholm AISI D2** is a premier **high-carbon, high-chromium, air-hardening cold work tool steel** renowned for its **exceptional wear resistance and high compressive strength**. As one of the most widely utilized "wear-resistant" grades in the tool steel family, D2 offers a significant performance advantage over lower-alloy steels like A2 and O1, making it the material of choice for long-run production tooling subjected to severe abrasive wear. While it exhibits moderate toughness, its primary attribute is outstanding resistance to material degradation under demanding service conditions, ensuring extended tool life and reduced downtime. --- ## **1. Key Characteristics & Advantages** - **Superior Wear Resistance:** Contains a high volume (approximately 12-14%) of hard chromium carbides, providing exceptional resistance to abrasive wear—significantly higher than A2 or O1 steels. - **High Compressive Strength:** Capable of withstanding extreme pressure without deformation, ideal for forming and coining applications. - **Good Dimensional Stability:** Air-hardening characteristic minimizes distortion and size change compared to oil-hardening steels. - **Deep Hardenability:** Can be through-hardened in substantial cross-sections (up to 125mm / 5"). - **Moderate Toughness:** Offers acceptable toughness for many applications when properly heat treated, though less than A2. - **Good Resistance to Softening:** Maintains hardness at moderately elevated temperatures (up to approximately 425°C / 800°F). - **Excellent Polishability:** The fine carbide structure allows for superb surface finishes, crucial for plastic and die-casting molds. --- ## **2. Typical Chemical Composition (Weight %)** | Element | Carbon (C) | Chromium (Cr) | Molybdenum (Mo) | Vanadium (V) | Silicon (Si) | Manganese (Mn) | | :--- | :---: | :---: | :---: | :---: | :---: | :---: | | **Content** | 1.50-1.60 | 11.00-13.00 | 0.70-1.20 | 0.50-1.10 | 0.10-0.60 | 0.20-0.60 | **Alloying Rationale:** - **Carbon (1.55%) & Chromium (12.00%):** Form a dense network of hard, primary chromium carbides (M₇C₃), the primary source of the steel's outstanding wear resistance. - **Molybdenum (1.00%):** Enhances hardenability, promotes secondary hardening, and refines the grain structure. - **Vanadium (0.80%):** Forms hard vanadium carbides that further increase wear resistance, improve toughness, and inhibit grain growth. - **Silicon & Manganese:** Aid in deoxidation and contribute to hardenability. --- ## **3. Physical & Mechanical Properties** ### **Physical Properties:** - **Density:** ~7.70 g/cm³ - **Thermal Conductivity:** ~20 W/(m·K) at 20°C - **Modulus of Elasticity:** ~210 GPa - **Coefficient of Thermal Expansion:** ~10.5 x 10⁻⁶/K (20-400°C) ### **Heat Treatment & Mechanical Data:** - **Annealed Hardness:** ~210-240 HBW - **Austenitizing Temperature:** 1020-1040°C (1870-1905°F) - **Quenching Medium:** Air (forced air recommended for reliable hardening) - **Tempering Temperature Range:** 180-550°C (355-1020°F). **Double or triple tempering is mandatory.** - **Typical Working Hardness:** **58-62 HRC** - *58-60 HRC (tempered at 400-500°C):* Favors toughness for forming applications. - *60-62 HRC (tempered at 180-250°C):* Maximizes wear resistance and compressive strength for cutting applications. - **Hardenability Depth:** Full through-hardening up to 125mm (5") thickness. --- ## **4. Main Applications** D2 is the benchmark for wear-resistant tooling in medium to high-volume production across multiple industries: - **Long-Run Blanking & Punching Dies:** For abrasive materials like electrical laminations, hardened steel, and composites. - **Forming, Drawing, and Coining Dies:** Where high pressure and wear are primary concerns. - **Shear Blades and Slitter Knives:** Industrial cutting blades for sheet metal, paper, and plastics. - **Thread Rolling and Forming Dies:** For high-volume fastener production. - **Precision Gauges and Rolls:** Calibration masters, feed rolls, and can-forming rolls. - **Plastic and Die-Casting Molds:** Core and cavity inserts for abrasive or corrosive plastics; ejector pins and cores for aluminum die-casting. - **Woodworking Tools:** Industrial planer knives, chipper knives, and veneer knives for processed wood and composites. - **Cold Extrusion Punches and Dies:** For non-ferrous metals. --- ## **5. Relevant International Standards & Comparable Grades** D2 is one of the most universally recognized tool steel grades. | Standard | Grade / Designation | Country/Region | Note | | :--- | :--- | :--- | :--- | | **AISI / ASTM A681** | **D2** | USA | The defining standard for this grade. | | **DIN / Werkstoff Nr.** | **1.2379 / X155CrVMo12-1** | Germany / EU | Standard European high-chromium steel. | | **JIS G4404** | **SKD11** | Japan | The predominant Japanese equivalent, widely used in Asia. | | **ISO 4957** | **160CrMoV12** | International | Corresponding ISO tool steel grade. | | **GB/T 1299** | **Cr12Mo1V1** | China | Common Chinese designation (similar to DIN 1.2379). | | **BS 4659** | **BD2** | UK | British standard designation. | **Important:** While D2 is a standardized grade, the **manufacturing process is critical**. Böhler-Uddeholm D2 offers superior carbide uniformity, internal cleanliness, and consistent heat treatment response compared to lower-quality generic materials, directly translating to better tool performance and reliability. --- ## **6. Supply Form & Processing** - **Available Forms:** Precision ground flat stock, round bars, blocks, and custom pre-machined blanks. - **Machining:** Fair machinability in annealed state. Requires rigid setups, sharp carbide tools, and moderate speeds/feeds. Its abrasiveness can accelerate tool wear. - **Grinding:** Can be challenging due to high hardness and carbide content. Use softer-grade aluminum oxide or CBN wheels with ample coolant. - **EDM (Electrical Discharge Machining):** Suitable. A stress-relieving temper is required after EDM to remove the brittle, transformed "white layer." - **Heat Treatment:** Requires precise control. Must be performed in a protective atmosphere or vacuum. Preheating at 800-850°C is essential. **Multiple tempering cycles (2-3) are critical** to transform retained austenite and achieve optimal stability and properties. - **Surface Treatment:** An excellent substrate for PVD coatings (TiN, TiCN, AlCrN) and for nitriding to further enhance surface hardness and wear resistance. --- ## **7. Selection Guidance & Conclusion** **When to choose Böhler-Uddeholm D2:** - **Abrasive wear** is the primary failure mechanism of the tool. - Applications require **maximum wear resistance** among standard non-PM cold work steels. - **Long production runs** where tool life extension justifies material and processing costs. - Tools require **high compressive strength** and good polishability (e.g., plastic molds). - **Moderate impact conditions** are present; for high-impact applications, a tougher grade like A2 may be preferable. **Comparison Context:** - **vs. A2:** Significantly higher wear resistance and compressive strength, but lower toughness and more difficult to grind. - **vs. PM Steels (e.g., VANADIS):** Lower cost, but PM steels offer superior toughness at equivalent wear levels or higher wear resistance at equivalent toughness. **Conclusion:** **Böhler-Uddeholm AISI D2** remains the **industry standard for wear-resistant cold work tooling**. Its unparalleled combination of high chromium carbide content and air-hardening capability provides a reliable solution for extending tool life in the most abrasive and demanding applications. While it demands respect during machining and heat treatment, its performance benefits are substantial. For toolmakers and engineers battling wear in medium to high-volume production, premium-quality D2 represents a proven, cost-effective investment in productivity and reliability. -:- For detailed product information, please contact sales. -: Bohler-Uddeholm AISI D2 Cold Work Tool Steel Specification Dimensions Size： Diameter 20-1000 mm Length <6880 mm Size:We can customized as required Standard： Per your request or drawing We can customized as required Properties（Theoretical） Chemical Composition -:- For detailed product information, please contact sales. -: Bohler-Uddeholm AISI D2 Cold Work Tool Steel Properties -:- For detailed product information, please contact sales. -:

Applications of Bohler-Uddeholm AISI D2 Cold Work Tool Steel -:- For detailed product information, please contact sales. -: Chemical Identifiers Bohler-Uddeholm AISI D2 Cold Work Tool Steel -:- For detailed product information, please contact sales. -:

Packing of Bohler-Uddeholm AISI D2 Cold Work Tool Steel -:- For detailed product information, please contact sales. -: Standard Packing: -:- For detailed product information, please contact sales. -: Typical bulk packaging includes palletized plastic 5 gallon/25 kg. pails, fiber and steel drums to 1 ton super sacks in full container (FCL) or truck load (T/L) quantities. Research and sample quantities and hygroscopic, oxidizing or other air sensitive materials may be packaged under argon or vacuum. Solutions are packaged in polypropylene, plastic or glass jars up to palletized 3351 gallon liquid totes Special package is available on request. E FORUs’ is carefully handled to minimize damage during storage and transportation and to preserve the quality of our products in their original condition