Spherical ASTM A229 Oil-tempered Steel Powder, Class I

ASTM A229 Oil-tempered Steel Spherical Powder Wire, Class I Product Information -:- For detailed product information, please contact sales. -: ASTM A229 Oil-tempered Steel Spherical Powder Wire, Class I Synonyms -:- For detailed product information, please contact sales. -: -:- For detailed product information, please contact sales. -: Spherical ASTM A229 Oil-tempered Steel Powder, Class I characteristics -:- For detailed product information, please contact sales. -: Spherical ASTM A229 Oil-tempered Steel Powder, Class I Particle Size -:- For detailed product information, please contact sales. -: -:- -:- 0-15μm ,5-25μm, 15-45μm, 15-53μm,20-63um, 45-75μm, 45-105μm, 45-150μm ,75-150μm. (Various granularities can be customized according to customer requirements) -:- For detailed product information, please contact sales. -:

Spherical ASTM A229 Oil-tempered Steel Powder, Class I Applicable processes -:- For detailed product information, please contact sales. -: Laser/electron beam additive manufacturing (SLM/EBM, 3D printing) Direct laser deposition (DLD) Used in thermal spray (TSA) Powder hot isostatic pressing (HIP) Metal injection molding (MIM) Powder metallurgy (PM) Laser cladding (LC), etc. -:- For detailed product information, please contact sales. -: Spherical ASTM A229 Oil-tempered Steel Powder, Class I Chemical Composition -:- For detailed product information, please contact sales. -: -:- For detailed product information, please contact sales. -: ASTM A229 Oil-tempered Steel Wire, Class I Product Information -:- For detailed product information, please contact sales. -: # **Product Datasheet: ASTM A229 Oil-Tempered Steel Wire, Class I** ## **1. Product Overview** **ASTM A229 Class I** is a **high-carbon steel wire** that has been **oil-tempered** to achieve an optimal balance of strength, toughness, and formability for mechanical spring applications. As the standard grade within the A229 specification, this wire undergoes a specialized heat treatment process—quenching in oil followed by tempering—that distinguishes it from hard-drawn wires (like A227). This process imparts superior fatigue resistance, excellent torsional properties, and greater ductility, making Class I wire the industry-preferred choice for a wide range of dynamic, moderate-stress spring applications where reliability and consistent performance are critical. ## **2. International Standards & Designations** | System/Authority | Designation | Specification Title / Relationship | | :--- | :--- | :--- | | **ASTM International** | **ASTM A229/A229M** | Standard Specification for Steel Wire, Oil-Tempered for Mechanical Springs | | **Class** | **Class I** | Standard Strength & Property Grade | | **SAE** | **SAE J217** | Oil-Tempered Spring Wire | | **ISO** | **ISO 8458-2** | Mechanical springs - Steel spring wire - Part 2: Oil hardened and tempered spring wire | | **EN (Europe)** | **EN 10270-2** | Steel wire for mechanical springs - Part 2: Oil hardened and tempered steel wire (Type FD) | | **JIS (Japan)** | **JIS G 3560** | Oil Tempered Steel Wire for Springs (SWO) | | **DIN (Germany)** | **DIN 17224** | Oil-hardened and tempered round steel spring wire | | **Common Names** | Oil-Tempered Wire (OT), OTA Wire, Class I OT, Tempered Spring Wire | ## **3. Chemical Composition (% by Weight)** The composition is based on high-carbon steel, optimized for response to oil quenching and tempering. | Element | ASTM A229 Requirement (Typical) | Typical % Range | | :--- | :--- | :--- | | **Carbon (C)** | **0.55 - 0.65** | 0.58 - 0.63 | | **Manganese (Mn)** | 0.50 - 0.90 | 0.70 - 0.85 | | **Phosphorus (P)** | ≤ 0.040 | ≤ 0.030 | | **Sulfur (S)** | ≤ 0.050 | ≤ 0.030 | | **Silicon (Si)** | 0.10 - 0.35 | 0.15 - 0.25 | | **Iron (Fe)** | Balance | Balance | **Manufacturing Process:** The wire begins as hot-rolled rod (similar to AISI 1065). It is first cold drawn to a size slightly above the final diameter, then undergoes a **continuous heat treatment process**: it is austenitized, quenched in oil, and tempered in-line. This produces a uniform **tempered martensite microstructure** throughout the cross-section, giving the wire its characteristic combination of properties. The final light drawing (sizing) may follow to achieve precise dimensions. ## **4. Mechanical & Physical Properties** Properties are standardized by wire diameter, with tensile strength decreasing as diameter increases. | Property | ASTM A229 Class I Specifications | Test Standard | Notes | | :--- | :--- | :--- | :--- | | **Condition** | **Oil-Tempered (Quenched & Tempered)** | -- | Uniform tempered martensite microstructure. | | **Tensile Strength** | **Diameter-Dependent (Representative):**
• 0.5 mm (0.020 in): 1850-2100 MPa (268-305 ksi)
• 2.0 mm (0.080 in): 1550-1750 MPa (225-254 ksi)
• 4.0 mm (0.160 in): 1400-1550 MPa (203-225 ksi)
• 6.0 mm (0.250 in): 1300-1450 MPa (189-210 ksi) | ASTM A370 / E8 | **Refer to ASTM A229 Table 2.** Slightly lower tensile but higher toughness than A227 Class I. | | **Torsion Test** | Required. Must withstand a significantly higher number of twists than hard-drawn wire before fracture. | ASTM A938 | **Superior ductility indicator.** Excellent for torsion springs. | | **Coiling & Wrapping Test** | Excellent formability. Must wrap tightly around itself without cracking. | Practical Test | Can be coiled into springs with very tight bend radii. | | **Surface Finish** | Typically a uniform, bluish-black oxide scale (temper color) from the heat treatment. Can be supplied bright (scale removed). | Visual | The oxide can provide some corrosion resistance and aid in lubrication during coiling. | | **Dimensional Tolerance** | Commercial tolerance per ASTM A229. | -- | | | **Modulus of Elasticity (E)** | ~200 GPa (29,000 ksi) | -- | | | **Shear Modulus (G)** | ~77 GPa (11,200 ksi) | -- | | | **Fatigue Life** | **Very Good** (Superior to hard-drawn wire under dynamic loading). | -- | Key advantage of the tempered structure. | ## **5. Key Characteristics & Advantages** * **Superior Fatigue Resistance:** The tempered martensite structure provides excellent resistance to crack initiation and propagation under cyclic loading, making it ideal for dynamic springs. * **Excellent Formability & Ductility:** Can be cold-coiled into complex shapes and tight radii with minimal risk of fracture, reducing spring manufacturing defects. * **Good Toughness:** Higher impact and shock load resistance compared to hard-drawn wires of similar strength. * **Uniform Properties:** The through-hardening heat treatment ensures consistent mechanical properties from surface to core. * **Good Stress Relaxation Resistance:** Performs better than hard-drawn wire in applications where springs are held under load for extended periods. * **Wide Availability:** The most common type of oil-tempered spring wire, available in a vast range of diameters. ## **6. Primary Applications** ASTM A229 Class I is the workhorse of the spring industry for dynamic and static applications requiring good durability. * **Automotive Suspension:** Coil springs for light vehicles, clutch springs, brake spring components. * **Torsion Springs:** High-performance applications in automotive seats, hinges, and industrial equipment. * **Valve Springs:** For internal combustion engines in lawn equipment, generators, and industrial machinery. * **Compression & Extension Springs:** In agricultural machinery, electrical devices, furniture, and conveyors. * **Spring Washers:** Especially where good fatigue life is needed. * **General Mechanical Engineering:** Any application requiring a reliable, formable, fatigue-resistant spring wire. ## **7. Processing & Fabrication Guidelines** * **Spring Coiling:** **Excellent for cold coiling.** Can be formed at room temperature on standard spring coiling equipment. Stress relieving after coiling is sometimes used for precision applications but is less critical than for hard-drawn wire due to its tempered state. * **Stress Relieving:** If required (e.g., for very tight tolerances), use **~230°C (450°F) for 30 minutes**. **DO NOT exceed 300°C (570°F)**, as this will overtemper the wire and reduce its strength. * **Welding:** **Not recommended** for finished springs. If necessary for fabrication prior to coiling, use with extreme caution and post-weld heat treatment. * **Plating/Coating:** Commonly plated (zinc, cadmium) for corrosion protection. Baking after plating (190-220°C for 2-4 hours) is recommended to mitigate hydrogen embrittlement risk, though the risk is lower than with highest-strength wires. * **Limitations:** Not suitable for elevated temperature service (above ~180°C / 350°F) where tempering effects continue. The oxide scale can be abrasive to coiling tooling. ## **8. Comparison with Key Spring Wires** | Wire Type (ASTM) | Process | Key Advantage | Typical Use Case vs. A229 Class I | | :--- | :--- | :--- | :--- | | **A227 Class I (Hard Drawn)** | Cold Drawn Only | **Lower Cost, Higher Tensile (Static)** | Use for low-cost, static load springs where fatigue is not a concern. | | **A229 Class I (Oil-Tempered)** | **Quenched & Tempered** | **Better Fatigue, Formability, Toughness** | **Default choice for dynamic springs.** | | **A228 (Music Wire)** | Special Patented & Drawn | **Highest Tensile, Best Surface** | Use for small, high-stress, high-cycle precision springs (e.g., watch springs). | | **A232 (Chrome Vanadium)** | Oil-Tempered Alloy | **Superior Fatigue & High-Temp Performance** | Use for high-performance automotive valve springs or elevated temp apps. | ## **9. Quality Assurance** Material is supplied with a test report certifying compliance with ASTM A229 Class I, including: * Chemical analysis * Tensile test results for the supplied diameter range * Torsion test results * Dimensional report --- **Disclaimer:** This datasheet is for informational purposes. For design and procurement, the complete requirements of the latest edition of **ASTM A229/A229M** shall govern, especially for diameter-specific tensile strength values. Consultation with a spring manufacturer is recommended for application-specific engineering. -:- For detailed product information, please contact sales. -: ASTM A229 Oil-tempered Steel Wire, Class I Specification Dimensions Size： Diameter 20-1000 mm Length <6413 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. -: ASTM A229 Oil-tempered Steel Wire, Class I Properties -:- For detailed product information, please contact sales. -:

Spherical ASTM A229 Oil-tempered Steel Powder, Class I Particle Size Description -:- For detailed product information, please contact sales. -: Applications of Spherical ASTM A229 Oil-tempered Steel Powder, Class I -:- For detailed product information, please contact sales. -: -:- For detailed product information, please contact sales. -: Applications of ASTM A229 Oil-tempered Steel Spherical Powder Wire, Class I -:- For detailed product information, please contact sales. -: Chemical Identifiers ASTM A229 Oil-tempered Steel Spherical Powder Wire, Class I -:- For detailed product information, please contact sales. -:

Packing of ASTM A229 Oil-tempered Steel Spherical Powder Wire, Class I -:- 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 Spherical Powder 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 2884 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