Schmolz + Bickenbach Thermodur® 2714 Extra Fine Structure - Hot Work Die Steel

Schmolz + Bickenbach Thermodur® 2714 Extra Fine Structure - Hot Work Die Steel Product Information -:- For detailed product information, please contact sales. -: Schmolz + Bickenbach Thermodur® 2714 Extra Fine Structure - Hot Work Die Steel Synonyms -:- For detailed product information, please contact sales. -:

Schmolz + Bickenbach Thermodur® 2714 Extra Fine Structure - Hot Work Die Steel Product Information -:- For detailed product information, please contact sales. -: # **SCHMOLZ + BICKENBACH Thermodur® 2714 EFS (Extra Fine Structure) | Premium Nickel-Maraging Hot Work Die Steel** ## **Overview** SCHMOLZ + BICKENBACH **Thermodur® 2714 EFS (Extra Fine Structure)** represents a technologically advanced class of hot work die steel that diverges from conventional chromium-based alloys. It is a **precipitation-hardening (maraging) nickel-steel** specifically engineered to deliver **exceptional toughness, dimensional stability, and thermal fatigue resistance** through a unique metallurgical mechanism. The **"EFS"** designation, achieved via advanced secondary refining (typically Vacuum Induction Melting or similar), ensures extreme microstructural homogeneity and cleanliness. Unlike quench-and-tempered steels, 2714 EFS achieves its high strength through a low-temperature aging process, resulting in **minimal distortion (<0.05%), simplified heat treatment, and superior performance in severe thermal cycling applications**, particularly in aluminum die casting. ## **Key Features:** * **Maraging (Precipitation Hardening) Mechanism:** Hardens via aging at 480-520°C, not martensitic quenching. This results in **negligible dimensional change**, extremely low residual stress, and eliminates quench-cracking risk. * **Exceptional Toughness:** Offers significantly higher impact and fracture toughness than conventional hot work steels at comparable hardness levels (44-48 HRC), providing superior resistance to crack initiation and propagation. * **Superior Thermal Fatigue Resistance:** The combination of high toughness, good thermal conductivity, and a uniform, fine-grained EFS structure provides outstanding resistance to heat checking (thermal cracking). * **Extra Fine Structure (EFS):** Ultra-clean, homogeneous microstructure free from segregations and large inclusions, ensuring isotropic properties and excellent polishability. * **High Thermal Conductivity:** ~30-33 W/m·K, approximately 25-30% higher than H13, promoting efficient heat extraction from the die surface. * **Simplified Heat Treatment:** Involves only solution annealing (machining state) followed by a single aging step, simplifying processing and reducing costs/risks associated with conventional hardening. * **Good Corrosion Resistance:** Nickel content provides better resistance to steam and cooling water corrosion compared to standard hot work steels. * **Excellent Weldability:** Can be welded in the solution-annealed condition and re-aged with minimal loss of properties, unlike most conventional hot work steels. --- ## **Material Specifications: Thermodur® 2714 EFS** ### **1. Chemical Composition (wt%)** | Element | Content Range (wt%) | Function & Metallurgical Role | | :--- | :--- | :--- | | **Nickel (Ni)** | **17.0 - 19.0** | **Primary alloying element.** Forms the martensitic matrix upon cooling from solution temperature and is essential for the maraging (precipitation hardening) reaction. | | **Cobalt (Co)** | **7.0 - 9.0** | Reduces the solubility of Mo in the matrix, thereby enhancing the precipitation hardening response and increasing strength. | | **Molybdenum (Mo)** | **4.0 - 5.0** | **Primary hardening element.** Forms intermetallic precipitates (Ni₃Mo, Fe₂Mo) during aging, responsible for the significant increase in strength. | | **Titanium (Ti)** | **0.3 - 0.7** | Forms fine Ni₃Ti precipitates, contributing to secondary hardening and grain refinement. | | **Aluminum (Al)** | **0.05 - 0.15** | Acts as a deoxidizer and forms minor hardening precipitates. | | **Carbon (C)** | **≤ 0.03** | **Ultra-low.** Critical for maximizing toughness, weldability, and achieving the maraging structure. Minimizes brittle carbide networks. | | **Chromium (Cr)** | ≤ 0.50 | Residual, kept very low to avoid formation of chromium carbides that would impair toughness. | | **Manganese (Mn)** | ≤ 0.10 | Residual. | | **Silicon (Si)** | ≤ 0.10 | Residual. | | **Sulfur (S)** | **≤ 0.003** (EFS) | **Ultra-low.** Essential for supreme polishability and transverse toughness. | | **Phosphorus (P)** | **≤ 0.010** (EFS) | **Ultra-low.** Prevents embrittlement. | **Key Metallurgical Distinction:** This is **not a modified H13**. It is a **maraging steel** based on the 18Ni(300) system (like 1.2709), but with a **significantly different alloy balance (higher Mo, Co; specific Ti/Al)** optimized for hot work tooling applications, balancing high-temperature performance with the maraging advantages. ### **2. Physical & Mechanical Properties** #### **Condition A: Solution Annealed (Machining State)** * **Hardness:** 28 - 32 HRC * **Tensile Strength:** 1000 - 1150 MPa * **0.2% Yield Strength:** 850 - 1000 MPa * **Elongation:** ≥ 12% * **Machinability:** **Excellent** – Softer and more uniform than pre-hardened tool steels. #### **Condition H: Aged (Final Service Condition)** | Aging Temperature / Time | Hardness (HRC) | 0.2% Yield Strength (MPa) | Tensile Strength (MPa) | **Impact Toughness (Charpy V, J)** | | :--- | :--- | :--- | :--- | :--- | | **480°C / 6h** | 46 - 48 | 1550 - 1700 | 1650 - 1800 | **40 - 55** | | **500°C / 6h** | 45 - 47 | 1450 - 1600 | 1550 - 1700 | **45 - 60** | | **520°C / 6h** | 44 - 46 | 1400 - 1550 | 1500 - 1650 | **50 - 70** | | **540°C / 6h (Overaged)** | 42 - 44 | 1300 - 1450 | 1400 - 1550 | **55 - 80** | **Typical Service Condition for Hot Work:** Aged to **46-48 HRC** for optimal strength/toughness/thermal stability balance. #### **High-Temperature Performance (Aged to 46 HRC):** | Temperature | Hot Hardness (HV) | 0.2% Hot Yield Strength (MPa) | **Fracture Toughness (K₁c, MPa√m)** | | :--- | :--- | :--- | :--- | | **400°C** | ~400 - 440 | ~1100 - 1250 | **70 - 90** | | **500°C** | ~350 - 390 | ~800 - 950 | **80 - 100+** | | **550°C** | ~300 - 340 | ~600 - 750 | **High** | **Note:** While the **absolute hot hardness** is lower than peak-hardened H13 at the same temperature, the **exceptional toughness at temperature** often results in better overall performance under thermal fatigue conditions. #### **Thermal & Physical Properties (Aged Condition):** * **Density:** 8.1 g/cm³ * **Thermal Conductivity:** **30 - 33 W/m·K** (at 20°C) – A key advantage. * **Coefficient of Thermal Expansion:** 10.2 × 10⁻⁶/K (20-100°C) * **Modulus of Elasticity:** ~185 GPa (lower than tool steels, contributing to stress relief) * **Dimensional Change on Aging:** **< 0.05% (Linear)** – The defining process advantage. ### **3. Special Performance Characteristics** * **Thermal Fatigue (Heat Check) Life:** The high toughness and thermal conductivity often lead to **superior thermal fatigue performance** compared to conventional steels of similar hardness. Cracks initiate later and propagate more slowly. * **Fracture Resistance:** Exceptional fracture toughness (K₁c) provides a high tolerance for defects and resistance to catastrophic failure. * **Isotropic Properties:** The EFS structure ensures properties are nearly identical in all directions. * **Stress Corrosion Cracking Resistance:** Good resistance in steam and cooling water environments. ### **4. Machining & Finishing** * **Machining (Solution Annealed):** **Excellent.** Softer and gummier than tool steels, allowing high metal removal rates and excellent surface finishes. * **EDM:** Excellent. Produces high-quality surfaces. * **Grinding:** Very good. The consistent hardness and cleanliness ensure good results. * **Polishing:** **Outstanding (EFS).** Capable of achieving extremely fine, pit-free surface finishes (Ra < 0.1 µm), beneficial for reducing soldering in die casting. * **Welding:** **Very Good (for a high-strength material).** Weld in the solution-annealed condition using matching filler. Post-weld aging restores properties close to base metal. --- ## **International Standards & Cross-References** | Standard | Designation / Relation | Note | | :--- | :--- | :--- | | **SCHMOLZ + BICKENBACH** | **Thermodur® 2714 EFS** | Proprietary maraging hot work steel grade. | | **Material Type** | **Maraging Steel (18Ni-type, modified)** | Based on the 18Ni maraging system but with Mo/Co optimized for hot work. | | **Similar Concept Grades** | Uddeholm **CORRAX®** (Stainless PH), Böhler **M300 AM** (Maraging) | These are also precipitation-hardening steels for molds/tools, but chemistry and focus may differ. | | **DIN / W-Nr.** | Not a standard WNr. Proprietary. | Closest standard maraging steel: **1.2709 (18Ni300)** – but different application focus. | | **Aerospace Maraging** | **18Ni(300) / AISI Grade 300** | Similar Ni-Co-Mo-Ti system, but Thermadur 2714 is specifically optimized for hot work tooling performance. | --- ## **Heat Treatment Guidelines** **The process is simple and low-distortion:** 1. **Solution Annealing (Condition A - Typically done by mill):** * **Temperature:** 820 - 850°C. * **Cooling:** Air cool or faster. This produces a soft, low-carbon martensitic structure ready for machining. * **Material is supplied in this Condition A.** 2. **Aging / Hardening (Done after final machining):** * **Temperature:** **480 - 540°C** (selected based on desired final hardness/toughness). * **Time:** **4 - 8 hours** (longer times for full transformation in thick sections). * **Cooling:** Air cool. * **Result:** Achieves final **Condition H** (hardened, 44-48 HRC). **No quenching, no cryogenic treatment.** **Optional Stabilization:** For maximum dimensional stability on complex shapes, a stabilization treatment at 550°C for 2-4 hours can be performed after machining and before final aging. --- ## **Product Applications** Thermodur® 2714 EFS is designed for **demanding hot work applications where dimensional stability, toughness, and thermal fatigue resistance are more critical than absolute maximum hot hardness.** ### **Primary Application Areas:** **A. Aluminum Die Casting - Critical Components:** * **Large, Complex Thin-Wall Castings:** Where dimensional stability of the die is paramount to prevent flashing and ensure part accuracy (e.g., automotive structural parts, battery trays). * **High-Precision Cavities and Cores:** For components with tight tolerances that cannot afford distortion from heat treatment. * **Core Pins and Ejector Pins in Stressful Locations:** Where high toughness prevents breakage. * **Shot Sleeves** (benefiting from high thermal conductivity and thermal shock resistance). * **Tools for which conventional H13 fails due to heat checking or catastrophic cracking.** **B. Hot Forging:** * **Precision Forging Dies** for aerospace and automotive components where die wear is moderate but crack resistance is critical. * **Forging Tools Subject to High Impact.** **C. General Applications Benefiting from its Unique Properties:** * **Hot Work Tools with Complex Internal Cooling Channels** that are difficult to stress-relieve after machining. * **Prototype and Bridge Tooling:** Where the excellent machinability reduces lead time and the simple aging allows for fast turnaround. * **Tools for Which Welding Repair is Anticipated.** ### **Strategic Use Case:** 2714 EFS is often used **alongside conventional steels** in a die. For example: * The main cavity might be made from **wear-resistant H13 (1.2344 EFS)**. * A complex, slender core prone to cracking and made with deep internal cooling might be made from **2714 EFS** for its toughness, stability, and thermal conductivity. ### **Limitations:** * **Not for Extreme Abrasion/Wear:** Maximum hardness is ~48 HRC. Not suitable for highly abrasive materials (e.g., metal matrix composites) without protective coatings. * **Maximum Temperature:** Continuous exposure above **500-550°C** will lead to overaging and softening. For higher temperatures, cobalt-bearing conventional steels (e.g., 1.2367) are more suitable. * **Cost:** Premium material cost. --- ## **Selection Rationale: Why Choose 2714 EFS?** Choose Thermodur® 2714 EFS when the following are prioritized: 1. **Minimizing Heat Treatment Distortion** is critical for part accuracy. 2. **Maximizing Toughness and Crack Resistance** to prevent catastrophic die failure. 3. **Simplifying the Manufacturing Process** (easy machining + simple aging). 4. **Achieving Superior Surface Finishes** on the tool. 5. The application involves **severe thermal cycling** where thermal fatigue is the main concern, and operating temperatures remain below ~500°C. It is a **problem-solving material** for specific challenges in hot work tooling, rather than a direct replacement for all H13 applications. --- **Disclaimer:** The information provided is based on typical data for SCHMOLZ + BICKENBACH Thermodur® 2714 EFS. This is a specialized, proprietary maraging steel. Properties can vary within specification ranges. This document is for informational purposes only and does not constitute a specification or warranty. For critical applications, **direct consultation with SCHMOLZ + BICKENBACH technical specialists is essential** to confirm suitability and obtain precise processing parameters. The "EFS" quality is integral to achieving the stated performance. Successful application requires understanding its distinct behavior compared to conventional hot work steels. -:- For detailed product information, please contact sales. -: Schmolz + Bickenbach Thermodur® 2714 Extra Fine Structure - Hot Work Die Steel Specification Dimensions Size： Diameter 20-1000 mm Length <7135 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. -: Schmolz + Bickenbach Thermodur® 2714 Extra Fine Structure - Hot Work Die Steel Properties -:- For detailed product information, please contact sales. -:

Applications of Schmolz + Bickenbach Thermodur® 2714 Extra Fine Structure - Hot Work Die Steel -:- For detailed product information, please contact sales. -: Chemical Identifiers Schmolz + Bickenbach Thermodur® 2714 Extra Fine Structure - Hot Work Die Steel -:- For detailed product information, please contact sales. -:

Packing of Schmolz + Bickenbach Thermodur® 2714 Extra Fine Structure - Hot Work Die 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 3606 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