AISI 1552 Steel, Annealed and Cold Drawn,UNS G15520

AISI 1552 Steel, Annealed and Cold Drawn Bar (UNS G15520) Product Information -:- For detailed product information, please contact sales. -: AISI 1552 Steel, Annealed and Cold Drawn Bar (UNS G15520) Synonyms -:- For detailed product information, please contact sales. -:

AISI 1552 Steel, Annealed and Cold Drawn Bar (UNS G15520) Product Information -:- For detailed product information, please contact sales. -: ### **Product Introduction: AISI 1552 Steel, Annealed & Cold Drawn Bar (UNS G15520)** **Overview** AISI 1552 (UNS G15520) in the **annealed and cold drawn** condition is a premium-processed, high-carbon manganese alloy steel bar engineered to overcome the extreme machining challenges of its base composition. This specialized two-step treatment involves a full annealing cycle to achieve a soft, ductile, and stress-free spheroidized microstructure, followed by a light cold drawing operation. The primary purpose of this sequence is to render this otherwise nearly unmachinable, ultra-high-strength steel suitable for the **precision machining of complex components**. It provides the optimal balance between exceptional machinability for its class, dimensional precision, and a moderate strength increase, serving as the essential pre-hardened manufacturing blank for components destined for final ultra-high-strength heat treatment. **Key Features & Advantages** * **Enabled Machinability for Ultra-High-Carbon Steel:** The annealing process is critical, transforming the hard, pearlitic structure into a soft, spheroidized condition. This dramatically reduces cutting forces, extends tool life, and makes feasible the machining of complex geometries that would be cost-prohibitive or impossible in the standard hot-rolled or cold drawn state. * **Precision Dimensional Control:** The subsequent cold drawing imparts excellent diameter tolerances (ASTM A108), superior straightness, and a bright, smooth surface finish. This ensures reliable performance in automated feeders and allows for the achievement of precise final part dimensions after intricate machining. * **Maximum Dimensional Stability:** The combination of complete stress relief from annealing and the uniform, minimal cold work provides the highest possible stability during machining. This is paramount for preventing warping or distortion in high-value, intricate components before their final, distortion-prone hardening process. * **Improved Handleability & Surface Quality:** While prioritizing machinability, the final drawing step provides a controlled increase in yield strength, improves surface finish, and enhances straightness compared to purely annealed stock, offering a more robust and higher-quality machining blank. * **Ideal, Predictable Pre-Condition for Final Hardening:** Creates a perfectly uniform, stress-free, and easily machinable blank. This uniformity is crucial for predictable and minimal distortion during the subsequent quenching & tempering process required to achieve the steel's ultimate strength properties. --- ### **1. Chemical Composition (Standard Conformance)** | Element | Standard Range (%) | Key Function | | :--- | :--- | :--- | | **Carbon (C)** | 0.47 – 0.55 | **Very high carbon content.** Provides the fundamental potential for ultra-high hardness (HRC 50-58+) and strength after final heat treatment. In the annealed state, carbon exists as soft, globular cementite particles. | | **Manganese (Mn)** | 1.20 – 1.50 | **Primary Alloying Element.** Provides exceptional hardenability potential, ensuring the steel will transform uniformly to high-carbon martensite throughout the section upon final quenching. | | **Phosphorus (P)** | ≤ 0.040 (max) | Residual element, minimized. | | **Sulfur (S)** | ≤ 0.050 (max) | Residual element, kept low. **Not a free-machining steel.** | | **Silicon (Si)** | 0.15 – 0.35 | Deoxidizer; solid solution strengthener. | | **Iron (Fe)** | Balance | Base element. | **Key International Standard Equivalents:** * **UNS:** G15520 * **AISI/SAE:** 1552 * **ASTM:** **A108** (Standard Specification for Steel Bar, Carbon and Alloy, Cold-Finished – Annealed and Cold Drawn is a specified condition) * **DIN (Germany):** No direct equivalent. * **EN (Europe):** No direct equivalent. --- ### **2. Typical Physical & Mechanical Properties (Annealed & Cold Drawn Condition)** *Note: Properties reflect a fully softened, pre-machining state. This condition exists solely to facilitate manufacturing.* | Property | Typical Value / Description | | :--- | :--- | | **Density** | 7.85 g/cm³ (0.284 lb/in³) | | **Tensile Strength** | 650 – 800 MPa (94 – 116 ksi) | | **Yield Strength (0.2% Offset)** | 420 – 580 MPa (61 – 84 ksi) | | **Elongation (in 50mm)** | 15% – 22% | | **Brinell Hardness (HB)** | 200 – 240 | | **Machinability (Comparison)** | **Fair (~50-55% of AISI 1212).** This is the defining feature – it makes precision machining of this grade technically and economically feasible. | | **Surface Roughness (Ra)** | 1.6 – 3.2 μm (63 – 125 μin). Bright, smooth commercial finish. | | **Tolerances** | Meets ASTM A108 cold-drawn tolerances. | | **Microstructure** | Fully spheroidized cementite in a ferrite matrix, with minimal strain from the final light draw. | --- ### **3. Product Applications** This material is specifically and exclusively designed as the starting stock for complex, ultra-high-strength components that require extensive precision machining prior to achieving final service hardness. * **Complex Ultra-High-Strength Tooling Blanks:** Blanks for punches, dies, molds, shear blades, and forming tools requiring extensive EDM, milling, or grinding to intricate shapes before final hardening. * **Critical Aerospace & Defense Components:** Complex actuator components, landing gear parts, and armament system parts machined to precise tolerances in a soft state before final heat treatment to extreme strength levels. * **High-Performance Automotive & Racing Components:** Stress-critical transmission gears, splined shafts, and suspension components where geometry precludes post-hardening machining. * **Specialty Wear Part Pre-Forms:** Components like sophisticated wear plates or tool holders with complex internal cooling channels or mounting geometries that must be machined before hardening. * **Precision Gearing for Heavy Industry:** Large, complex gear blanks for mining or energy applications that are machined prior to through-hardening. * **Any component** where geometric complexity mandates machining in a soft state, and the final service requirement demands the ultra-high hardness and strength unique to the 1552 chemistry after proper quenching & tempering. --- ### **4. Process Rationale & Critical Considerations** * **Process Sequence Imperative:** 1. **Full Spheroidize Anneal:** A critical heat treatment that softens the steel for machining. Without this step, production machining is impractical. 2. **Light Cold Draw:** Applied primarily for dimensional control and surface enhancement, not for significant strengthening. * **Fundamental Purpose & Limitation:** **This condition exists solely to enable machining.** The annealed microstructure possesses inadequate strength for any structural service. Its **only** purpose is to be machined to final or near-final dimensions prior to a separate, final hardening heat treatment. * **Mandatory Subsequent Heat Treatment:** Components made from this material **MUST** undergo a carefully controlled quenching and tempering process to achieve their design properties (typically aiming for HRC 48-55+). This two-step approach (machine soft, then harden) is selected specifically to **avoid the severe distortion, cracking, and tool wear** associated with machining fully hardened material or quenching a complex part from the as-rolled state. * **Distortion Management Strategy:** Even with this optimal pre-condition, the final quench will induce dimensional changes. The uniform, stress-free state provided by this material allows these changes to be more predictable, enabling compensation in the machining stage or the use of post-hardening grinding for critical dimensions. * **Total Cost Justification:** This is a premium processing route. The justification lies entirely in the **total lifecycle cost savings and enabled design** for complex parts: it reduces machining time/cost, enables complex geometries, improves part quality, and increases heat treatment yield. * **Not a Final Material:** **AISI 1552 Annealed and Cold Drawn is a manufacturing intermediary, not a finished material.** --- **Disclaimer:** **AISI 1552 Annealed and Cold Drawn is a specialized manufacturing intermediary for ultra-high-strength components.** It is supplied in a condition suitable **only for machining**, **not for service**. The final component **must** undergo quenching & tempering to achieve functional properties. This process route requires integrated design, machining, and heat treatment expertise to manage distortion. Selection should be based on a comprehensive analysis of part geometry, final performance requirements, and total manufacturing cost. Always specify and validate the final heat treatment cycle during the design phase. -:- For detailed product information, please contact sales. -: AISI 1552 Steel, Annealed and Cold Drawn Bar (UNS G15520) Specification Dimensions Size： Diameter 20-1000 mm Length <5051 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 1552 Steel, Annealed and Cold Drawn Bar (UNS G15520) Properties -:- For detailed product information, please contact sales. -:

Applications of AISI 1552 Steel, Annealed and Cold Drawn Bar (UNS G15520) -:- For detailed product information, please contact sales. -: Chemical Identifiers AISI 1552 Steel, Annealed and Cold Drawn Bar (UNS G15520) -:- For detailed product information, please contact sales. -:

Packing of AISI 1552 Steel, Annealed and Cold Drawn Bar (UNS G15520) -:- 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 1522 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