AISI 9255 Steel, annealed

AISI 9255 Steel, annealed at 845°C (1550°F) Product Information -:- For detailed product information, please contact sales. -: AISI 9255 Steel, annealed at 845°C (1550°F) Synonyms -:- For detailed product information, please contact sales. -:

AISI 9255 Steel, annealed at 845°C (1550°F) Product Information -:- For detailed product information, please contact sales. -: **Product Introduction: AISI 9255 Steel, Annealed at 845°C (1550°F)** **1. Product Overview** AISI 9255 is a high-silicon, high-carbon spring steel known for its exceptional fatigue strength, high elastic limit, and excellent hardenability. Supplied in the annealed condition (at ~845°C / 1550°F), it offers optimal machinability and formability for subsequent manufacturing processes. The material achieves its outstanding mechanical properties after appropriate quenching and tempering heat treatment, making it a premium choice for demanding high-stress spring and torsion applications. **2. International Standards & Designations** This steel grade is recognized under several international standards, ensuring consistent quality and specifications: * **AISI (USA):** 9255 * **ASTM (USA):** A29 (Standard Specification for Steel Bars, Carbon and Alloy, Hot-Wrought and Cold-Finished) * **SAE (USA):** J403, J412 (Chemical Composition) * **UNS:** G92550 * **EN (Europe):** 55Si7 (1.0909) - The closest comparable grade. * **JIS (Japan):** SUP7 - A similar silicon-manganese spring steel. **3. Chemical Composition (Typical % by Weight)** The composition is balanced to provide the core characteristics of high strength and resilience. * **Carbon (C):** 0.50 - 0.60 * **Manganese (Mn):** 0.70 - 0.95 * **Silicon (Si):** 1.80 - 2.20 *(Key element for strength and hardenability)* * **Phosphorus (P):** ≤ 0.035 * **Sulfur (S):** ≤ 0.040 * **Iron (Fe):** Balance **4. Physical & Mechanical Properties (Annealed Condition)** In the annealed state, the material is supplied with a softened microstructure (spheroidized or pearlitic) to facilitate shaping. * **Condition:** Annealed (~845°C, slow cool) * **Hardness (Brinell):** Typically 187 - 229 HB * **Tensile Strength:** ~655 MPa (95 ksi) *[Post-heat treatment values are significantly higher]* * **Yield Strength:** ~415 MPa (60 ksi) * **Elongation:** ~25% * **Modulus of Elasticity:** ~205 GPa (30 x 10⁶ psi) * **Density:** 7.85 g/cm³ *(Note: After oil quenching and tempering, hardness can reach 45-50 HRC, with tensile strength exceeding 1725 MPa (250 ksi).)* **5. Key Product Features & Benefits** * **Superior Fatigue Resistance:** Ideal for components undergoing repeated cyclic loading. * **High Elastic Limit:** Can endure significant deformation and return to its original shape. * **Good Hardenability:** Silicon content promotes deep and uniform hardening upon quenching. * **Machinability (Annealed State):** Good for drilling, turning, and shaping before final heat treatment. * **Wear Resistance:** After hardening, exhibits good resistance to surface degradation. **6. Primary Applications** AISI 9255 is predominantly used in the manufacture of high-performance mechanical springs and resilient components, including: * **Heavy-Duty Coil Springs & Leaf Springs:** For automotive suspensions, railway systems, and heavy machinery. * **Torsion Bars:** Used in vehicle suspension systems and stabilizer bars. * **High-Stress Clutch Springs & Diaphragms.** * **Industrial Disc Springs (Belleville Washers).** * **Agricultural Machinery Parts** requiring high strength and durability. **7. Processing Considerations** * **Forming/Machining:** Best performed in the supplied annealed condition. * **Heat Treatment:** Requires final quenching (typically in oil) and tempering to achieve desired spring properties. Care must be taken to prevent decarburization during heating. * **Welding:** Not generally recommended due to high carbon equivalent; if necessary, requires pre-heat, post-heat, and specialized procedures. **Conclusion** AISI 9255 steel in the annealed condition is a versatile, process-ready material for engineers designing critical, high-stress spring applications. Its unique silicon-carbon chemistry, combined with proper heat treatment, delivers an exceptional combination of strength, resilience, and fatigue life that meets rigorous international standards for performance and reliability. -:- For detailed product information, please contact sales. -: AISI 9255 Steel, annealed at 845°C (1550°F) Specification Dimensions Size： Diameter 20-1000 mm Length <6392 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 9255 Steel, annealed at 845°C (1550°F) Properties -:- For detailed product information, please contact sales. -:

Applications of AISI 9255 Steel, annealed at 845°C (1550°F) -:- For detailed product information, please contact sales. -: Chemical Identifiers AISI 9255 Steel, annealed at 845°C (1550°F) -:- For detailed product information, please contact sales. -:

Packing of AISI 9255 Steel, annealed at 845°C (1550°F) -:- 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 2863 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