ATI Allegheny Ludlum H13 Tool Steel, UNS T20813

ATI Allegheny Ludlum H13 Tool Steel, UNS T20813 Product Information -:- For detailed product information, please contact sales. -: ATI Allegheny Ludlum H13 Tool Steel, UNS T20813 Synonyms -:- For detailed product information, please contact sales. -:

ATI Allegheny Ludlum H13 Tool Steel, UNS T20813 Product Information -:- For detailed product information, please contact sales. -: # **Product Introduction: ATI Allegheny Ludlum H13 Tool Steel (UNS T20813)** ## **1. Overview** **ATI Allegheny Ludlum H13 Tool Steel** is a premium **chromium-molybdenum-vanadium hot work die steel** that serves as the global industry standard for aluminum die casting, hot forging, and high-temperature plastic injection molding applications. Designated as **UNS T20813** and commonly known as **AISI H13**, this alloy is engineered to deliver an exceptional combination of **high-temperature strength, thermal fatigue resistance, toughness, and thermal conductivity**. As a versatile hot work steel, H13 maintains its hardness and structural integrity under cyclic thermal loading, resisting the primary failure modes of heat checking (thermal fatigue cracking) and gross deformation. ATI's production ensures a fine, uniform microstructure that optimizes these properties for extended die life and reliable performance in the most demanding thermal processing environments. ## **2. International Standards & Specifications** H13 is one of the most universally recognized and specified hot work tool steels worldwide. * **Primary Standard Designations:** * **UNS T20813:** Unified Numbering System designation. * **AISI H13:** American Iron and Steel Institute classification. * **ASTM A681:** Standard Specification for Tool Steels Alloy. * **Key International Equivalents:** * **DIN 1.2344 / EN ISO 4957 X40CrMoV5-1:** The primary European standard. * **JIS G4404 SKD61:** Japanese Industrial Standard. * **GB/T 1299 4Cr5MoSiV1:** Chinese national standard. * **ISO 4957:** **X40CrMoV5-1**. * **Common Trade Names:** Universally referred to as **H13 Tool Steel**, **Hot Work Die Steel**, or by premium brand names such as **DIEVAR, ORVAR, QRO 90** for enhanced variants. ## **3. Chemical Composition (Weight %, per ASTM A681)** The composition is balanced to provide high tempering resistance ("red hardness"), toughness, and thermal fatigue resistance. | Element | Composition Range (%) | Role & Benefit | |---------|----------------------|----------------| | **Carbon (C)** | 0.32 – 0.45 | Provides base strength and hardness. Optimized to balance wear resistance with toughness at elevated temperatures. | | **Chromium (Cr)** | 4.75 – 5.50 | **Primary alloy for tempering resistance and oxidation resistance.** Enables "secondary hardening" during tempering, allowing the steel to retain hardness at high service temperatures. Also provides resistance to oxidation and molten aluminum wash. | | **Molybdenum (Mo)** | 1.10 – 1.75 | **Critical for high-temperature strength and toughness.** Enhances hardenability, improves creep resistance, and increases toughness, especially at the core of thick sections. | | **Vanadium (V)** | 0.80 – 1.20 | **Key for wear resistance and grain refinement.** Forms fine, stable vanadium carbides (VC) that provide wear resistance and inhibit grain growth, contributing to thermal fatigue resistance. | | **Silicon (Si)** | 0.80 – 1.20 | **Enhances oxidation resistance and thermal fatigue strength.** Strengthens the ferrite matrix and improves the steel's ability to withstand thermal cycling. | | **Manganese (Mn)** | 0.20 – 0.50 | Aids in hardenability and deoxidation. | ## **4. Typical Physical & Mechanical Properties (Heat Treated)** * **Recommended Heat Treatment (for Die Casting Dies):** * **Preheating:** 750-800°C (1380-1470°F) – **Critical** to prevent cracking. * **Austenitizing:** **1010-1040°C (1850-1905°F).** Vacuum or atmosphere controlled to prevent decarburization. * **Quenching:** **Air cool or high-pressure gas quench.** Oil quenching is possible but increases distortion risk. * **Tempering:** **Double or triple tempering is standard.** Temper immediately. Typical range: **540-600°C (1000-1110°F)** for die casting applications, achieving a final hardness of **44-48 HRC**. Higher tempering temperatures increase toughness. * **Mechanical Properties (Hardened & Double Tempered to ~46-48 HRC):** * **Hardness (Operating):** 44 – 52 HRC (adjustable via tempering; 44-48 HRC typical for die casting). * **Tensile Strength:** 1450 – 1650 MPa (210,000 – 239,000 psi) * **Yield Strength (0.2% Offset):** 1250 – 1450 MPa (181,000 – 210,000 psi) * **Impact Toughness (Charpy V-Notch):** **25 – 40 J (18 – 29 ft-lb)** – **Excellent for a hot work steel,** crucial for resisting crack initiation from thermal stress. * **Hot Hardness at 540°C (1000°F):** ~42-45 HRC – Demonstrates excellent "red hardness" or tempering resistance. * **Thermal Conductivity:** **~ 24-28 W/m·K** – **Relatively high for an alloy steel,** aiding in heat extraction from the die surface and reducing thermal gradients. * **Key Performance Features:** * **Thermal Fatigue Resistance:** **Exceptional.** The primary reason for its selection. Resists the initiation and growth of network cracks ("heat checking") caused by repeated heating and cooling cycles. * **Toughness at Operating Hardness:** High impact strength helps prevent catastrophic die failure from mechanical shock or crack propagation. * **Resistance to Softening (Temper Resistance):** Maintains hardness during prolonged exposure to elevated service temperatures (up to ~600°C / 1110°F). * **Machinability (Annealed):** Good. * **Physical Properties:** * **Density:** 7.80 g/cm³ * **Coefficient of Thermal Expansion:** 11.5 × 10⁻⁶/°C (20–100°C) * **Modulus of Elasticity:** 210 GPa (30.5 × 10⁶ psi) ## **5. Product Application** ATI H13 Tool Steel is the dominant material for a vast range of hot work tooling applications. * **Aluminum, Magnesium, & Zinc Die Casting:** * **Cavities, cores, slides, and inserts** (the core application). * **Shot sleeves, nozzles, and goosenecks.** * **Ejector pins and cores.** * **Hot Forging and Extrusion:** * **Forging dies and inserts** for brass, aluminum, and steel. * **Extrusion dies** for aluminum profiles. * **Plastic Injection Molding:** * **Molds for high-temperature engineering plastics** (PEEK, PPS, PEI). * **Hot runner systems** (manifolds, nozzles). * **Molds for abrasive or corrosive plastics** (filled resins, PVC). * **Other Hot Work:** * **Glass mold tooling.** * **Hot shearing blades and punches.** ## **6. Key Features & Advantages** * **Superior Thermal Fatigue Resistance:** The optimized combination of alloying elements provides outstanding resistance to heat checking, extending die life in cyclic heating applications. * **Excellent Combination of Toughness and Strength:** Withstands both thermal shock and high mechanical clamping/impact forces, reducing catastrophic failure risk. * **High Thermal Conductivity:** For an alloy steel, it conducts heat well, helping to manage surface temperatures and thermal stresses. * **Good Hardenability and Dimensional Stability:** Air hardens with minimal distortion, suitable for large, complex dies. * **Good Machinability and Polishability:** Can be machined and finished to high-quality surfaces. * **Good Weldability and Repairability:** Can be repaired using matching filler metals and proper procedures. * **Proven and Predictable Performance:** Decades of global use have established it as a reliable and well-understood material. ## **7. Processing Guidelines** * **Machining:** Perform roughing in the annealed condition. A stress relief cycle after rough machining is highly recommended. * **Heat Treatment:** **Must be performed in a controlled atmosphere (vacuum preferred).** Follow preheat, austenitize, and **double temper** cycles precisely. Do not interrupt the quench. * **Surface Treatment:** Often **nitrided (gas or plasma)** or coated with **PVD (CrN, TiAlN)** to further enhance surface hardness, resistance to soldering, and erosion resistance. * **Welding:** Requires preheat (400-450°C), use of matching H13 filler rods, and immediate post-weld tempering. **Summary:** ATI Allegheny Ludlum H13 Tool Steel is the cornerstone material for hot work tooling. Its unparalleled balance of high-temperature strength, thermal fatigue resistance, and toughness has made it the default choice for aluminum die casting dies, hot forging tools, and high-performance plastic molds worldwide. For engineers and toolmakers facing the extreme challenges of thermal cycling, mechanical stress, and high-temperature exposure, H13 provides a reliable, proven, and cost-effective solution that maximizes tool life and production uptime. It is not merely a material specification but a fundamental enabler of modern high-pressure die casting and thermal processing industries. -:- For detailed product information, please contact sales. -: ATI Allegheny Ludlum H13 Tool Steel, UNS T20813 Specification Dimensions Size： Diameter 20-1000 mm Length <7057 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. -: ATI Allegheny Ludlum H13 Tool Steel, UNS T20813 Properties -:- For detailed product information, please contact sales. -:

Applications of ATI Allegheny Ludlum H13 Tool Steel, UNS T20813 -:- For detailed product information, please contact sales. -: Chemical Identifiers ATI Allegheny Ludlum H13 Tool Steel, UNS T20813 -:- For detailed product information, please contact sales. -:

Packing of ATI Allegheny Ludlum H13 Tool Steel, UNS T20813 -:- 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 3528 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