Crucible Steel Wire,CHRO-MOW® Tool Steel Wire, AISI H12

Crucible Steel Wire CHRO-MOW® Tool Steel Wire, AISI H12 Product Information -:- For detailed product information, please contact sales. -: Crucible Steel Wire CHRO-MOW® Tool Steel Wire, AISI H12 Synonyms -:- For detailed product information, please contact sales. -:

Crucible Steel CHRO-MOW® Tool Steel, AISI H12 Product Information -:- For detailed product information, please contact sales. -: # **Product Introduction: Crucible Steel CHRO-MOW® (AISI H12) Tool Steel** Crucible Steel CHRO-MOW® is a premium, air-hardening, chromium-molybdenum-tungsten hot work tool steel that conforms to the AISI H12 specification. Positioned within the versatile hot work steel family, H12 is engineered to deliver a **balanced combination of good hot hardness (red hardness), excellent thermal fatigue resistance, high toughness, and moderate wear resistance**. The name "CHRO-MOW" reflects its core alloying elements: **Chromium** and **Molybdenum**, with **Tungsten** (the "W") providing additional high-temperature stability. CHRO-MOW® is particularly valued for applications involving **aluminum and magnesium alloy die casting, as well as certain forging and extrusion operations**. Its balanced chemistry provides a reliable middle ground between the higher-toughness H11 and the higher-wear-resistance H13, making it a versatile and predictable choice for a wide range of hot work applications where a single steel must perform well across multiple performance metrics without being the absolute best in any one category. It is known for its stability, good polishability, and resistance to heat checking. --- ## **1. Chemical Composition (Weight %)** The composition of H12 is a balanced chromium-molybdenum system with significant tungsten, distinguishing it from H11 and H13. | **Element** | **Carbon (C)** | **Chromium (Cr)** | **Molybdenum (Mo)** | **Tungsten (W)** | **Vanadium (V)** | **Silicon (Si)** | | :--- | :--- | :--- | :--- | :--- | :--- | :--- | | **Content** | 0.30 - 0.40 | 4.75 - 5.50 | 1.25 - 1.75 | 1.00 - 1.70 | 0.40 - 0.60 | 0.80 - 1.20 | | **Role** | Provides base strength and hardness. Optimized for a balance of toughness and wear resistance at elevated temperatures. | Primary contributor to deep air hardenability, oxidation resistance, and hot hardness. | Enhances hardenability, hot strength, and resistance to tempering. A key element for hot work properties. | **Distinguishing element.** Contributes significantly to **hot hardness and resistance to deformation** at high temperatures through solid solution strengthening. | Forms fine, stable vanadium carbides that improve wear resistance, refine grain size, and enhance toughness. | Improves oxidation resistance and provides solid solution strengthening at elevated temperatures. | *Note: Iron (Fe) constitutes the remainder. The presence of tungsten (1.0-1.7%) is the key compositional difference from H13 (~0% W) and H11 (~0% W), giving H12 unique high-temperature characteristics.* --- ## **2. Physical & Mechanical Properties** *Typical properties after proper heat treatment to a common hot work hardness of 44-48 HRC.* * **Density:** ~7.80 g/cm³ (0.282 lb/in³) * **Modulus of Elasticity:** ~210 GPa (30.5 x 10⁶ psi) * **Thermal Conductivity:** ~25 W/m·K at 20°C. * **Coefficient of Thermal Expansion:** ~11.5 x 10⁻⁶/°C (20-200°C) * **Hot Hardness (Red Hardness):** **Very Good.** The tungsten content provides excellent resistance to softening at elevated temperatures (up to ~540°C / 1000°F), often outperforming H13 at higher ends of the temperature range. * **Thermal Fatigue Resistance:** **Excellent.** Its balanced composition provides very good resistance to the initiation and growth of heat-check cracks, comparable to or slightly better than H13 in many die casting applications. * **Toughness:** **Very Good.** Higher than H13 due to lower carbon and vanadium, but slightly lower than H11. Offers a good balance for withstanding thermal and mechanical shock. * **Wear Resistance:** **Good.** Adequate for most hot work applications involving aluminum and magnesium. Better than H11, but generally lower than H13 due to H13's higher vanadium content. * **Dimensional Stability & Polishability:** **Excellent.** Air hardening minimizes distortion, and its microstructure allows it to be polished to a high surface finish, which is critical for aluminum die casting to prevent soldering and improve part release. --- ## **3. Heat Treatment** Heat treatment follows standard hot work steel protocols, with attention to the tungsten content. * **Annealing:** Heat to 845-870°C (1555-1600°F), slow cool. Annealed hardness: 192-229 HB. * **Stress Relieving:** 650-675°C (1200-1250°F), hold, then slow cool. * **Preheating:** **Critical.** Preheat thoroughly at 790-815°C (1450-1500°F). * **Austenitizing:** **995-1040°C (1825-1900°F).** A common range is **1010-1025°C (1850-1875°F)**. * **Quenching:** **Air quench** (forced air preferred) or high-pressure gas quench. * **Tempering:** **Mandatory Double or Triple Temper.** Temper immediately after quenching. **Minimum of two tempers**, each for 2+ hours. * **Must be tempered to a minimum of 540°C (1000°F)** or higher. A typical range for achieving 44-48 HRC is **565-600°C (1050-1110°F)**. * **Never use in the as-quenched state.** --- ## **4. Key Applications** CHRO-MOW® (H12) is a classic and versatile hot work steel, especially dominant in specific sectors. * **Aluminum Die Casting:** The traditional and still widely used material for cavities, cores, plunger tips, and goosenecks in aluminum pressure die casting. * **Magnesium Die Casting:** Dies and tooling for hot-chamber magnesium die casting. * **Hot Extrusion Dies:** For extruding aluminum, magnesium, and brass alloys. * **Hot Forging Dies:** For forging non-ferrous metals and some steel forging applications. * **Plastic Molds:** For high-temperature engineering plastics or where excellent polishability is required. * **General Hot Work Tooling:** Where a balanced combination of properties is needed for reliable, long-run performance. --- ## **5. International Standards & Cross-References** Crucible CHRO-MOW® conforms to the AISI H12 specification. * **AISI/SAE:** **H12** * **UNS:** T20812 * **European (EN):** **1.2606** (X30WCrV9-3) - This is a close equivalent, though European grades often have higher tungsten. * **Japanese (JIS):** **SKD6** (Note: SKD6 can correspond to both H11 and H12 types; specific chemistry defines the match). * **ISO:** HS 9-2-2 (approximate classification) * **Common Trade Names:** H12 Tool Steel, Chromium-Molybdenum-Tungsten Hot Work Steel. --- ## **6. Advantages & Limitations** **Advantages:** * **Excellent All-Round Balance:** Provides a reliable, well-proven combination of hot hardness, thermal fatigue resistance, and toughness. * **Superior Hot Hardness (vs. H13):** The tungsten content gives it an edge in maintaining hardness at very high operating temperatures. * **Excellent Polishability:** Critical for high-quality surface finishes on cast parts. * **Good Dimensional Stability:** Air hardening ensures minimal distortion of complex dies. * **Proven Reliability:** Decades of successful use, especially in aluminum die casting, with well-understood behavior. **Limitations:** * **Moderate Wear Resistance:** May not be as wear-resistant as H13 in highly abrasive casting or forging applications (e.g., with high-silicon aluminum). * **Not the Toughest (H11) nor Most Wear-Resistant (H13):** It is a compromise grade, which may not be optimal for extreme conditions favoring one property over the other. * **Susceptibility to Decarburization:** Requires controlled atmosphere heat treatment. --- ## **7. Summary** **Crucible Steel CHRO-MOW® (AISI H12) is the quintessential balanced hot work tool steel, a trusted and versatile performer that has formed the backbone of the aluminum die casting industry for generations.** Its success lies in its ability to deliver a harmonious blend of high-temperature strength, resistance to thermal cycling, and sufficient toughness for demanding production environments. While newer grades like H13 have gained popularity for broader applications, H12 remains the specialist's choice for applications where its specific balance—particularly its tungsten-enhanced hot hardness and excellent polishability—delivers unmatched performance and reliability. For tooling engineers seeking a predictable, proven, and high-performing material for demanding hot work, CHRO-MOW® continues to be a benchmark of excellence. -:- For detailed product information, please contact sales. -: Crucible Steel CHRO-MOW® Tool Steel, AISI H12 Specification Dimensions Size： Diameter 20-1000 mm Length <6994 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. -: Crucible Steel CHRO-MOW® Tool Steel, AISI H12 Properties -:- For detailed product information, please contact sales. -:

Applications of Crucible Steel Wire CHRO-MOW® Tool Steel Wire, AISI H12 -:- For detailed product information, please contact sales. -: Chemical Identifiers Crucible Steel Wire CHRO-MOW® Tool Steel Wire, AISI H12 -:- For detailed product information, please contact sales. -:

Packing of Crucible Steel Wire CHRO-MOW® Tool Steel Wire, AISI H12 -:- 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 Wire 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 3465 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