High-Aluminum Iron Wire, heat-resistant gray Iron Wire

High-Aluminum Iron Wire, heat-resistant gray Iron Wire Product Information -:- For detailed product information, please contact sales. -: High-Aluminum Iron Wire, heat-resistant gray Iron Wire Synonyms -:- For detailed product information, please contact sales. -:

High-Aluminum Iron, heat-resistant gray iron Product Information -:- For detailed product information, please contact sales. -: ## **Product Introduction: High-Aluminum Heat-Resistant Gray Iron** High-Aluminum Heat-Resistant Gray Iron is a unique and highly specialized class of cast iron, differentiated by its exceptionally high aluminum content. This alloy is engineered to provide supreme oxidation and scaling resistance in extreme high-temperature environments, particularly under cyclic heating and cooling conditions where thermal shock is a primary concern. Its performance is fundamentally derived from the formation of a continuous, tenacious, and self-regenerating alumina (Al₂O₃) oxide layer on the surface, which acts as an outstanding barrier against oxygen penetration. This material excels in service temperatures ranging from **900°C to 1100°C (1650°F to 2010°F)**, offering a cost-effective alternative to some nickel-based superalloys in specific oxidizing atmospheres. While offering unmatched oxidation resistance for a cast iron, its high aluminum content introduces distinct challenges in casting and machining, making it a niche material for applications where its specific advantages are paramount. --- ### **1. Chemical Composition** The extraordinary heat resistance is primarily imparted by aluminum, which drastically alters the microstructure and surface behavior of the iron. **Typical Composition Ranges:** | Element | Standard Grade (Moderate Al) | High-Performance Grade (High Al) | Primary Function in Heat Resistance | | :--- | :--- | :--- | :--- | | **Aluminum (Al)** | **18.0 - 22.0%** | **22.0 - 28.0%** | **Core alloying element.** Forms a highly stable, continuous, and adherent **Al₂O₃ (alumina) surface scale** with extremely low oxygen diffusivity. This provides exceptional protection against oxidation, carburization, and sulfur attack. Dissolved Al also stabilizes a ferritic matrix. | | **Carbon (C)** | **1.50 - 2.20%** | **1.20 - 1.80%** | Exists primarily as fine graphite flakes or as complex carbides (e.g., κ-carbide, (Fe,Al)₃C). Lower carbon improves ductility and castability in high-Al grades. | | **Silicon (Si)** | 1.00 - 3.00% | 1.00 - 2.50% | Improves fluidity, enhances oxidation resistance synergistically with Al, and promotes ferrite stability. | | **Chromium (Cr)** | 0 - 2.0% (Optional) | 0 - 3.0% (Optional) | Sometimes added to further enhance scaling resistance and high-temperature strength. | | **Iron (Fe)** | Balance | Balance | Base metal. | **Microstructural Note:** The microstructure is characterized by an **aluminum-rich ferritic matrix** (α-Fe(Al) solid solution) containing a dispersion of **graphite and/or complex iron-aluminum carbides (κ-carbide)**. The high Al content suppresses pearlite formation entirely, ensuring a fully ferritic structure with excellent growth resistance but limited room-temperature strength. --- ### **2. Physical & Mechanical Properties at Room & Elevated Temperature** This material sacrifices some room-temperature properties for unparalleled high-temperature stability and surface protection. | Property | Typical Value / Description | | :--- | :--- | | **Microstructure** | Ferritic matrix (α-Fe(Al)) with fine graphite flakes and/or κ-carbide precipitates. | | **Density** | ~6.5 - 6.8 g/cm³ (Significantly lower than other cast irons due to light Al). | | **Tensile Strength (Room Temp)** | **150 - 250 MPa (22 - 36 ksi)** – Relatively low due to the soft ferritic matrix. | | **Compressive Strength** | Moderate. | | **Hardness (Room Temp)** | **180 - 250 HB** | | **Elongation** | **Very Low (<1%).** Remains brittle at room temperature. | | **Maximum Service Temperature** | **900°C - 1100°C (1650°F - 2010°F)** in oxidizing atmospheres. Performs well in cyclic service. | | **Oxidation/Scaling Resistance** | **Exceptional.** The Al₂O₃ scale is one of the most stable and protective oxides, offering oxidation resistance superior to high-chromium irons in pure oxidizing conditions. | | **Growth Resistance** | **Excellent.** The stable ferritic matrix and absence of phase transformations up to the melting point prevent growth. | | **Thermal Conductivity** | **Low (~20-25 W/m·K).** Lower than other gray irons, which can affect heat transfer but may reduce thermal stress gradients. | | **Thermal Shock Resistance** | **Very Good to Excellent.** The low modulus of elasticity, moderate strength, and stable microstructure provide good resistance to crack initiation from thermal cycling. | | **Abrasion/Wear Resistance at RT** | Poor to Fair. The soft ferritic matrix offers little wear resistance. | | **Machinability** | **Poor.** The material is gummy and abrasive, causing severe tool wear. Special tools and techniques are required. | --- ### **3. Key Product Advantages & Characteristics** * **Unrivaled Oxidation Resistance:** The alumina (Al₂O₃) scale provides arguably the best protection against high-temperature oxidation available in any cast iron system. * **Excellent Resistance to Thermal Cycling:** Low thermal expansion coefficient and stable structure yield superb resistance to thermal fatigue and spalling. * **Light Weight:** Significantly lower density than other heat-resistant alloys, beneficial for moving parts or where weight is a factor. * **Good Sulfidation Resistance:** Performs well in sulfur-containing atmospheres where nickel-based alloys may suffer. * **Cost-Effectiveness for High-Temp Oxidizing Service:** A lower-cost alternative to heat-resistant steels and nickel alloys in applications where its specific oxidation resistance is the primary requirement. --- ### **4. Product Applications** This material is used in specialized, high-temperature oxidizing environments where scaling is the primary failure mechanism. * **Heat Treatment Furnaces:** Components such as trays, pots, and fixtures for annealing, normalizing, and tempering, especially where clean, scale-free work is required. * **Ceramic & Powder Metallurgy:** Sintering trays, boats, and setters for firing ceramics and metal powders at high temperatures. * **Chemical Processing:** Components exposed to high-temperature oxidizing gases or molten salts. * **Glass Manufacturing:** Certain tools and handling equipment for molten glass. * **Energy Sector:** Parts for heat recuperators and air preheaters in high-temperature flue gas streams. --- ### **5. International Standards** High-Aluminum Iron is a highly specialized material and is not as uniformly standardized as other heat-resistant cast irons. It is often covered by proprietary specifications or national standards. | Standard / Basis | Title / Scope | Common Designations / Notes | | :--- | :--- | :--- | | **Proprietary Alloys** | Manufacturer-specific grades | Often designated as **Fe-Al alloys** or **Aluminum Iron** with specified Al content (e.g., Fe-24Al-2C). | | **GB/T 27748** | *Heat resistant austenitic cast iron* (Chinese) | While focused on austenitic, related standards or appendices may reference high-Al ferritic grades. Specific grades like **RQA** (Heat Resisting Aluminum Iron) may be defined in older or industry standards. | | **ASTM A297** | *Standard Specification for Heat-Resistant Iron-Chromium and Iron-Chromium-Nickel Alloy Castings* | While primarily for steels (HK, HP, etc.), the compositional philosophy for high-Al alloys is similar, though not explicitly listed. | | **JIS G5152** | *Heat-resistant ferritic alloy castings for high-temperature service* (Japanese) | May encompass high-Al cast irons under broad categories for ferritic heat-resistant materials. | | **Technical Literature** | Research papers & foundry catalogs | Often referred to as **High-Aluminum Cast Iron (HAI)** or **Al-Alloyed Gray Iron**. | **Specification Note:** Due to the lack of ubiquitous international standards, procurement is typically based on **detailed technical agreements between supplier and user**, specifying exact chemical composition ranges (especially Al, C, Si), required high-temperature performance tests (e.g., oxidation weight gain after 100 hours at 1000°C), and accepted casting quality standards. --- ### **Conclusion** High-Aluminum Heat-Resistant Gray Iron is a niche but powerful engineering material that leverages the unparalleled protective qualities of an **alumina (Al₂O₃) surface scale**. Its primary domain is in **severe, high-temperature oxidizing environments up to 1100°C**, where its resistance to scaling outperforms even high-chromium irons. The trade-offs—including **lower room-temperature strength, poor machinability, and challenging casting characteristics**—define its specialized application scope. For components like sintering trays and furnace fixtures where long-term oxidation resistance under cycling conditions is the sole critical criterion, it provides a uniquely effective and often cost-optimized solution. -:- For detailed product information, please contact sales. -: High-Aluminum Iron, heat-resistant gray iron Specification Dimensions Size： Diameter 20-1000 mm Length <6485 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. -: High-Aluminum Iron, heat-resistant gray iron Properties -:- For detailed product information, please contact sales. -:

Applications of High-Aluminum Iron Wire, heat-resistant gray Iron Wire -:- For detailed product information, please contact sales. -: Chemical Identifiers High-Aluminum Iron Wire, heat-resistant gray Iron Wire -:- For detailed product information, please contact sales. -:

Packing of High-Aluminum Iron Wire, heat-resistant gray Iron Wire -:- 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 2956 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