AISI Type A8 Tool Steel Flange

1,We Manufacturing processes are primarily classified into four types: 1:Forging, 2:Casting, 3:Cutting, 4:Rolling. 2,We can manufacture in accordance with these standards. Standards: GB Series (Chinese Standards), JB Series (Machinery Standards), HG Series (Chemical Industry Standards), ASME B16.5 (American Standards), BS4504 (British Standards), DIN (German Standards), and JIS (Japanese Standards). Internationally, there are two primary systems of pipe flange standards: the European system, represented by the German DIN standards (including those of the former Soviet Union), and the American system, represented by the US ANSI pipe flange standards. Other common standards include: the Chinese Ministry of Machinery Industry standards (JB series), the Ministry of Chemical Industry standards (HG series), the Chinese National Standard *GB/T 9112–9124-2010 Steel Pipe Flanges*, as well as US standards (ASME B16.5), British standards (BS4504), German standards (DIN), Japanese standards (JIS), and marine standards (CBM), among others. The nominal pressure ratings for the PN series are designated by "PN" and comprise the following nine levels: PN2.5, PN6, PN10, PN16, PN25, PN40, PN63, PN100, and PN160. The nominal pressure ratings for the Class series are designated by "Class" and comprise the following six levels: Class150, Class300, Class600, Class900, Class1500, and Class2500. Flange Classification 1. **According to Chemical Industry Standards:** Flanges are classified as follows: Plate Flat Welding Flange (PL), Necked Flat Welding Flange (SO), Necked Butt Welding Flange (WN), Integral Flange (IF), Socket Welding Flange (SW), Threaded Flange (Th), Butt Welding Ring Loose Flange (PJ/SE), Blind Flange (BL), Flat Welding Ring Loose Flange (PJ/PJ), and Lined Blind Flange (BL(s)). 2. **According to Petrochemical (SH) Industry Standards:** Flanges are classified as follows: Threaded Flange (PL), Butt Welding Flange (WN), Flat Welding Flange (SO), Socket Welding Flange (SW), Loose Flange (LJ), and Blind Flange (no specific designation). 3. **According to Machinery (JB) Industry Standards:** Flanges are classified as follows: Integral Flange, Butt Welding Flange, Plate Flat Welding Flange, Butt Welding Ring Plate Loose Flange, Flat Welding Ring Plate Loose Flange, Lap Joint Ring Plate Loose Flange, and Blind Flange. 4. **According to Connection Method/Type:** Flanges are classified as follows: Plate Flat Welding Flange, Necked Flat Welding Flange, Necked Butt Welding Flange, Socket Welding Flange, Threaded Flange, Blind Flange, Necked Butt Welding Ring Loose Flange, Flat Welding Ring Loose Flange, Ring-Type Joint (RTJ) Flange and Blind Flange, Large-Diameter Plate Flange, Large-Diameter High-Neck Flange, Figure-8 Blind Plate, Butt Welding Ring Loose Flange, etc. 5. **According to the Component Being Connected:** Flanges can be classified into Vessel Flanges and Pipe Flanges. 6. **According to Structural Type:** Flanges include Integral Flanges, Threaded Flanges, Flat Welding Flanges, Butt Welding Flanges, Lap Joint (Loose/Swivel) Flanges, and Blind Flanges. A flange—also referred to as a flange plate or rim—is a component used to connect shafts to one another, or, more commonly, to join the ends of pipes. Flanges are also utilized at the inlet and outlet ports of equipment to facilitate connections between two devices—for instance, the flange on a speed reducer. A "flange connection" or "flanged joint" refers to a detachable joint assembly comprising three interconnected elements—a flange, a gasket, and bolts—that together form a sealed structural unit. In the context of piping systems, a "pipe flange" specifically denotes a flange used for plumbing within the installation; when applied to equipment, it refers to the inlet or outlet flange of that specific device. Flanges feature a series of holes through which bolts are inserted to securely fasten the two flanges together, while a gasket placed between the flanges ensures a leak-proof seal. Flanges are broadly categorized into three types: threaded (screw-in) flanges, welded flanges, and clamp-type flanges. Flanges are invariably used in pairs; threaded flanges are suitable for low-pressure piping applications, whereas welded flanges are required for systems operating at pressures exceeding 4 kilograms per square centimeter. A sealing gasket is inserted between the two flange plates, which are then firmly secured using bolts. The thickness of a flange—as well as the specifications of the bolts used to fasten it—vary depending on the specific pressure rating required for the application. When connecting equipment such as water pumps or valves to piping systems, the corresponding connection points on these devices are often manufactured in the shape of a matching flange; this method of attachment is also referred to as a "flange connection." Generally, any connecting component that utilizes bolts to join and seal the perimeters of two flat surfaces—such as the joints in ventilation ducts—is termed a "flange"; such components may collectively be classified as "flange-type parts." However, since such a connection often constitutes merely a *portion* of a larger device—for instance, the interface between a flange and a water pump—it would be inappropriate to classify the entire water pump itself as a "flange-type part." Conversely, smaller components—such as valves—that feature such flanged interfaces may indeed be appropriately categorized as "flange-type parts." -:- For detailed product information, please contact sales. -: AISI Type A8 Tool Steel Flange Product Information -:- For detailed product information, please contact sales. -: AISI Type A8 Tool Steel Flange Synonyms -:- For detailed product information, please contact sales. -:

AISI Type A8 Tool Steel Product Information -:- For detailed product information, please contact sales. -: # **Product Introduction: AISI Type A8 Tool Steel** ## **Overview** AISI Type A8 is a **medium-carbon, high-chromium, air-hardening tool steel** uniquely formulated to provide **exceptional dimensional stability combined with good toughness and wear resistance**. Positioned between the general-purpose A2 and high-wear A7 grades, A8 features balanced alloying that emphasizes **minimal distortion during heat treatment, reliable hardenability, and resistance to thermal fatigue**. Its distinct composition makes it particularly suitable for **precision tooling applications requiring stable dimensions under thermal cycling conditions**, such as certain die casting and plastic molding applications. --- ## **Chemical Composition (Typical Weight %)** The composition emphasizes chromium for stability and hardenability with controlled carbon. | Element | Content (%) | | :--- | :--- | | Carbon (C) | 0.50 - 0.60 | | Chromium (Cr) | 4.75 - 5.50 | | Molybdenum (Mo) | 1.15 - 1.65 | | Manganese (Mn) | 0.40 - 0.70 | | Silicon (Si) | 0.75 - 1.10 | | Vanadium (V) | ≤ 0.35 | | Sulfur (S) | ≤ 0.03 | | Phosphorus (P) | ≤ 0.03 | | **Iron (Fe)** | **Balance** | **Key Role of Elements:** * **Moderate Carbon (0.50-0.60%):** Lower than most cold work steels, providing improved toughness and reduced distortion while maintaining adequate hardness. * **High Chromium (4.75-5.50%):** Provides excellent air-hardening characteristics, good wear resistance through chromium carbide formation, and moderate corrosion resistance. * **Elevated Silicon (0.75-1.10%):** Higher than typical for tool steels; improves resistance to thermal fatigue (heat checking) and promotes graphitization in certain conditions. * **Molybdenum (1.15-1.65%):** Enhances hardenability, provides secondary hardening response during tempering, and improves high-temperature strength. * **Controlled Vanadium:** Limited to maintain machinability while providing some grain refinement. --- ## **Physical & Mechanical Properties** *Properties shown are for properly heat treated material.* | Property | Typical Value / Description | | :--- | :--- | | **Density** | 7.84 g/cm³ (0.283 lb/in³) | | **Hardness (Annealed)** | 200 - 235 HB (Brinell) | | **Hardness (Hardened & Tempered)** | **54 - 60 HRC** (Typically used at 56-58 HRC) | | **Wear Resistance** | **Good.** Better than low-alloy steels but less than high-carbon grades like A2 or D2. Suitable for moderate wear applications. | | **Toughness** | **Very Good to Excellent.** Higher than A2 at equivalent hardness due to lower carbon content. Good resistance to chipping. | | **Dimensional Stability** | **Exceptional.** Excellent for an air-hardening steel; minimal distortion and size change during heat treatment. | | **Machinability (Annealed)** | **Good** (Approx. 65-70% of 1% carbon steel). Better than higher-carbon tool steels. | | **Grindability** | **Good.** Less challenging than high-vanadium steels. | | **Thermal Fatigue Resistance** | **Good to Very Good.** The elevated silicon content improves resistance to heat checking under thermal cycling. | | **Thermal Conductivity** | ~ 28.5 W/m·K at 20°C | | **Coefficient of Thermal Expansion** | ~ 10.8 × 10⁻⁶/°C (20-100°C) | --- ## **Heat Treatment Guidelines** | Process | Parameters | | :--- | :--- | | **Annealing** | Heat to 815-845°C (1500-1550°F), slow furnace cool at ≤22°C/hour to 480°C (900°F), then air cool. Result: 200-235 HB. | | **Stress Relieving** | 650-675°C (1200-1250°F) for 1-2 hours, air cool. | | **Preheating** | Preheat at 650-760°C (1200-1400°F). | | **Austenitizing** | 955-980°C (1750-1795°F). Soak time: 20-30 minutes per inch of thickness. | | **Quenching** | **Air quench** in still or forced air. For complex shapes, forced air is recommended. | | **Tempering** | Temper immediately after quenching. Double temper at 175-540°C (350-1000°F) for minimum 2 hours per cycle. For high toughness: 425-540°C (800-1000°F). | --- ## **Product Applications** AISI A8 is particularly suited for applications requiring **dimensional stability under thermal stress and good overall mechanical balance**. ### **Primary Applications:** 1. **Die Casting Dies & Inserts:** For aluminum and zinc die casting where thermal fatigue resistance is important (though not as heat-resistant as dedicated H-series hot work steels). 2. **Plastic Injection Molds:** For abrasive or corrosive plastics where dimensional stability and moderate wear resistance are needed. 3. **Precision Gauges & Fixtures:** Where exceptional dimensional stability is required. 4. **Forming Dies & Punches:** For medium-duty forming applications requiring good toughness. 5. **Shear Blades & Cutting Tools:** For materials where a balance of wear and toughness is needed. 6. **Machine Tool Components:** Wear plates, guide rails, and cam plates requiring stability. 7. **Thread Rolling Dies:** For softer materials where dimensional precision is critical. ### **Industry Usage:** - **Tool & Die Making** - **Plastics Manufacturing** - **Light Metal Casting** - **Precision Manufacturing** --- ## **International Standards & Cross-Reference** AISI A8 has limited direct international equivalents. | Standard | Designation | Equivalent / Similar Grade | | :--- | :--- | :--- | | **AISI/SAE (USA)** | **Type A8** | - | | **UNS (USA)** | **T30108** | - | | **ASTM (USA)** | A681 | Grade A8 | | **Europe (EN)** | - | No direct common equivalent | | **Germany (DIN)** | - | No direct common equivalent | | **Japan (JIS)** | - | No direct common equivalent | | **Similar Grade** | **H12 Mod** | Modified hot work steel with similar Cr-Mo balance | **Note:** A8 is a relatively uncommon grade with few true international equivalents. Its composition shares similarities with some modified H-series hot work steels but is classified as a cold work steel. --- ## **Advantages & Considerations** ### **Advantages:** 1. **Excellent Dimensional Stability:** Minimal distortion during heat treatment. 2. **Good Toughness:** Superior to higher-carbon tool steels at equivalent hardness. 3. **Improved Thermal Fatigue Resistance:** Better than typical cold work steels due to silicon content. 4. **Reliable Hardenability:** Good through-hardening characteristics with air quenching. 5. **Balanced Performance:** Good combination of wear resistance, toughness, and stability. ### **Considerations:** 1. **Moderate Wear Resistance:** Not suitable for highly abrasive applications. 2. **Lower Maximum Hardness:** Cannot achieve the high hardness levels of A2, A7, or D2. 3. **Limited High-Temperature Capability:** Not a true hot work steel; limited to approximately 400°C (750°F) continuous service. 4. **Limited Availability:** Less commonly stocked than A2 or D2. --- ## **Technical Comparison Summary** - **vs. A2:** A8 has **better toughness and dimensional stability** but **lower wear resistance and maximum hardness**. - **vs. H13 (Hot Work):** H13 has **superior high-temperature strength and thermal fatigue resistance** but may have **lower dimensional stability** during heat treatment. - **vs. O1 (Oil-Hardening):** A8 offers **far better dimensional stability** (air vs. oil quench) and **better toughness**. --- ## **Special Considerations** ### **Thermal Fatigue Performance:** The elevated silicon content (0.75-1.10%) in A8 provides improved resistance to heat checking compared to standard cold work steels. This makes it suitable for applications involving moderate thermal cycling, though it does not match the performance of dedicated hot work steels like H13 for high-temperature applications. ### **Graphitization Potential:** The combination of moderate carbon and elevated silicon can promote graphitization under certain prolonged high-temperature exposures (above 425°C/800°F for extended periods). This should be considered for applications involving sustained elevated temperatures. --- ## **Conclusion** AISI Type A8 tool steel occupies a **specialized niche within the cold work steel family**, offering a **unique combination of dimensional stability, toughness, and moderate thermal fatigue resistance**. Its balanced composition—featuring moderate carbon, high chromium, and elevated silicon—makes it particularly valuable for **precision tooling applications that experience moderate thermal cycling** or where exceptional dimensional stability is paramount. While not as wear-resistant as A2 or as thermally resistant as H13, A8 provides an **optimal compromise for applications requiring stability under varying thermal conditions** with good overall mechanical performance. It represents a thoughtful engineering solution for tooling applications that fall between traditional cold work and hot work steel requirements, particularly where the dimensional predictability of air hardening is essential for manufacturing accuracy. -:- For detailed product information, please contact sales. -: AISI Type A8 Tool Steel Specification Dimensions Size： Diameter 20-1000 mm Length <6668 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. -: AISI Type A8 Tool Steel Properties -:- For detailed product information, please contact sales. -:

Applications of AISI Type A8 Tool Steel Flange -:- For detailed product information, please contact sales. -: Chemical Identifiers AISI Type A8 Tool Steel Flange -:- For detailed product information, please contact sales. -:

Packing of AISI Type A8 Tool Steel Flange -:- 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 Flange 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 3139 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