Compacted Graphite Cast Iron Rod/Bar (CG)

Compacted Graphite Cast Iron Rod (CG) Product Information -:- For detailed product information, please contact sales. -: Compacted Graphite Cast Iron Rod (CG) Synonyms -:- For detailed product information, please contact sales. -:

Compacted Graphite Cast Iron (CG) Product Information -:- For detailed product information, please contact sales. -: **Product Technical Data Sheet: Compacted Graphite Iron (CGI / CG Cast Iron)** **1. Product Overview** Compacted Graphite Iron (CGI), also known as Vermicular Graphite Iron, is an advanced engineering material that uniquely bridges the performance gap between conventional gray iron (GI) and ductile iron (DI). It is characterized by a distinctive graphite morphology where the graphite particles are interconnected, appearing as "worm-like" or vermicular shapes under a microscope. This structure is neither fully flake-like (as in gray iron) nor spheroidal (as in ductile iron), but a controlled intermediate form. CGI delivers a superior combination of high tensile strength, good ductility and toughness, excellent thermal conductivity, and reliable fatigue performance. It is increasingly specified for high-integrity, high-stress components, particularly in the automotive and heavy machinery sectors, where it offers an optimal balance of performance, castability, and cost. **2. Governing International Standards** The classification and testing of CGI are defined by several key international standards: * **Primary Standard: ASTM A842** - *Standard Specification for Compacted Graphite Iron Castings*. This is the main ASTM specification, classifying CGI by grade based on tensile strength (e.g., Grade 350, 400, 450). * **Testing Standard: ASTM E8/E8M** - *Standard Test Methods for Tension Testing of Metallic Materials*. * **Microstructure Evaluation: ASTM A247** - *Standard Test Method for Evaluating the Microstructure of Graphite in Iron Castings*. It defines the compacted (vermicular) graphite shapes (Type III, IV). * **International Standards:** * **ISO 16112** - *Compacted (vermicular) graphite cast irons — Classification*. Defines grades (e.g., JV/JVH 350, 400, 450, 500, 600). * **EN 16079:2011** - *Founding — Compacted (vermicular) graphite cast irons*. * **GB/T 26655-2022** (China) - *Compacted (vermicular) graphite cast irons*. * **Foundry Process Control: GFA (German Foundrymen's Association) Guidelines** are often referenced for process best practices due to the tight control required. **3. Typical Chemical Composition** Achieving the compacted graphite structure requires precise control of composition and the use of specialized magnesium- or cerium-based inoculants (compacting agents). The key is to maintain a residual level of "compacting elements" (Mg, Ce, Ti) within a very narrow "processing window"—enough to prevent flake graphite but insufficient to form spheroids. | Element | Target Range (%) | Critical Role in CGI | | :--- | :--- | :--- | | **Carbon Equivalent (CE)** | 4.2 - 4.6 | Ensures castability and graphite formation. | | **Carbon (C)** | 3.5 - 3.9 | High carbon for fluidity and damping. | | **Silicon (Si)** | 1.8 - 2.7 | Promotes ferrite; adjusted for desired matrix (pearlite/ferrite ratio). | | **Magnesium (Mg)** | **0.010 - 0.025** | The most critical element. Must be tightly controlled within this "CG window". Too low → Flake Graphite; Too high → Spheroidal Graphite. | | **Cerium (Ce) / Rare Earths** | Often used with/without Mg to widen the processing window and counteract detrimental elements. | | **Sulfur (S)** | Low, < 0.02 | Must be low and stable; high S consumes Mg, making control difficult. | | **Copper (Cu)** | 0 - 1.0 | Primary pearlite promoter for strength. | | **Tin (Sn)** | 0 - 0.1 | Strong pearlite stabilizer. | | **Molybdenum (Mo)** | 0 - 0.8 | Used for increased strength, hardenability, and high-temperature stability. | **4. Physical & Mechanical Properties (Typical As-Cast or Heat-Treated)** CGI offers a unique property profile, making it a true hybrid material. | Property | Typical Range | Comparison & Notes | | :--- | :--- | :--- | | **Tensile Strength** | 350 - 600 MPa (Grades 350 - 600) | **~75% higher than equivalent gray iron**, approaching lower-grade ductile iron. | | **Yield Strength (0.2% Offset)** | 250 - 450 MPa | Excellent yield-to-tensile ratio. | | **Elongation (%)** | **3 - 10%** | **Key advantage:** Has measurable ductility (unlike brittle gray iron), though lower than high-ductility DI. | | **Modulus of Elasticity** | 140 - 165 GPa | ~20-25% higher than gray iron, closer to ductile iron and steel. Provides greater stiffness. | | **Hardness (Brinell)** | 170 - 270 HBW | Depends on matrix (ferritic, pearlitic, or austempered). | | **Thermal Conductivity** | ~36 - 42 W/m·K | **~75% of Gray Iron, but ~2x higher than Ductile Iron.** Critical for managing heat in engines. | | **Fatigue Strength (Rotating Bending)** | 200 - 260 MPa (40-50% of UTS) | **Superior to both GI and DI** at comparable tensile strength. Excellent for cyclic loading. | | **Damping Capacity** | Good | Better than DI, but lower than flake graphite GI. | | **Machinability** | Challenging | Generally more difficult than GI and ferritic DI (similar to pearlitic DI) due to its toughness and abrasive graphite shape. Requires optimized tooling and parameters. | **5. Product Applications** CGI is the material of choice for demanding applications where a combination of strength, stiffness, fatigue resistance, and thermal management is required. * **Automotive Powertrain (Primary Market):** * **Engine Blocks & Cylinder Heads:** For high-performance diesel and increasingly for gasoline engines. Superior strength allows for thinner walls (lightweighting) and higher cylinder pressures. Excellent thermal conductivity reduces hot spots and thermal fatigue. * **Exhaust Manifolds & Turbocharger Housings:** For its excellent thermal fatigue and oxidation resistance at elevated temperatures. * **Brake Discs & Drums:** For heavy-duty vehicles, offering better thermal cracking resistance than gray iron. * **Heavy-Duty & Industrial Machinery:** * **Large Gearboxes & Housings** * **Hydraulic Valve Bodies & Pump Housings** * **Press Frames & Machine Tool Bases** (where damping is still beneficial but higher stiffness is needed). * **Wind Energy:** **Gearbox Housings** for large turbines, where its high fatigue strength and stiffness under complex loading are critical. * **Railway:** **Brake Discs** and engine components. **6. Ordering & Specification Information** When specifying CGI, it is crucial to define: * **Material Grade:** Per **ASTM A842 (e.g., Grade 450)** or **ISO 16112 (e.g., JV 450)**. * **Microstructure Requirements:** Minimum percentage of compacted graphite (typically >80% CGI, with limits on nodule and flake graphite). * **Matrix Structure:** As-cast ferritic/pearlitic, or specified heat-treated condition (e.g., austempered for maximum strength and wear resistance). * **Key Performance Criteria:** E.g., minimum tensile, yield, elongation, and often a required fatigue strength or stiffness (Young's Modulus) value. -:- For detailed product information, please contact sales. -: Compacted Graphite Cast Iron (CG) Specification Dimensions Size： Diameter 20-1000 mm Length <6515 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. -: Compacted Graphite Cast Iron (CG) Properties -:- For detailed product information, please contact sales. -:

Applications of Compacted Graphite Cast Iron Rod (CG) -:- For detailed product information, please contact sales. -: Chemical Identifiers Compacted Graphite Cast Iron Rod (CG) -:- For detailed product information, please contact sales. -:

Packing of Compacted Graphite Cast Iron Rod (CG) -:- 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 Rod 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 2986 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