Maraging 300,Udimar 300 ,UNS K93120,E FORU

British Specs:，American Specs:AMS 6514 Bar, Tube and Forgings AMS 6521 Sheet, Strip and Plate MIL-S-46850 TYPE 4 ASTM A579 / AMS 6514 Powder，German Specs:WS 1.6354 WS 1.6358

### **Technical Data Sheet: Maraging Steel 300 / Udimar 300 (UNS K93120)** --- #### **1. Product Overview** **Maraging Steel 300** (commercially known as **Udimar 300**, **UNS K93120**) is an ultra-high-strength martensitic age-hardening steel that represents the highest strength grade in the standard maraging steel family. This nickel-cobalt-molybdenum steel achieves its exceptional mechanical properties through a low-temperature aging process that precipitates intermetallic compounds, providing the highest strength-to-weight ratio in the maraging steel series while maintaining good toughness and excellent dimensional stability. --- #### **2. Chemical Composition (Weight %)** | Element | Min (%) | Max (%) | Function | |---------|----------|----------|----------| | **Nickel (Ni)** | 18.00 | 19.00 | Matrix strengthening, toughness | | **Cobalt (Co)** | 8.50 | 9.50 | Solid solution strengthening | | **Molybdenum (Mo)** | 4.60 | 5.20 | Precipitation hardening | | **Titanium (Ti)** | 0.50 | 0.80 | Primary age-hardening element | | **Aluminum (Al)** | 0.05 | 0.15 | Secondary age-hardening element | | **Carbon (C)** | - | 0.03 | Impurity control | | **Manganese (Mn)** | - | 0.10 | - | | **Silicon (Si)** | - | 0.10 | - | | **Iron (Fe)** | - | - | Balance | --- #### **3. Mechanical & Physical Properties** **A. Mechanical Properties (After Solution Annealing & Aging)** - **Tensile Strength:** 2,000 - 2,140 MPa (290 - 310 ksi) - **Yield Strength (0.2% Offset):** 1,930 - 2,070 MPa (280 - 300 ksi) - **Elongation:** 8 - 10% - **Reduction in Area:** 40 - 50% - **Hardness:** 52 - 56 HRC - **Fracture Toughness (K_Ic):** 50 - 70 MPa√m - **Impact Toughness (Charpy V):** 15 - 25 J **B. Physical Properties** - **Density:** 8.00 g/cm³ (0.289 lb/in³) - **Modulus of Elasticity:** 185 GPa (26.8 × 10⁶ psi) - **Poisson's Ratio:** 0.30 - **Thermal Conductivity:** 18.0 - 20.0 W/m·K - **Thermal Expansion Coefficient:** 10.4 - 10.9 × 10⁻⁶/°C (20 - 100°C) - **Electrical Resistivity:** 0.65 - 0.70 μΩ·m --- #### **4. Product Applications** **Aerospace & Defense** - **Rocket motor cases** and missile components - **Aircraft landing gear** high-strength components - **Helicopter rotor** systems and components - **Ordnance components** and gun barrels - **Space vehicle** structural members **Tooling & Manufacturing** - **Precision molds** for high-pressure injection molding - **Die-casting tools** and cores - **Extrusion press** components - **High-performance gears** and shafts - **Fixture components** and special tooling **High-Performance Industrial** - **Racing components** requiring maximum strength - **High-strength fasteners** and special bolts - **Hydraulic components** for extreme pressure - **Test equipment** and load cells - **Optical mounting** systems --- #### **5. International Standards & Specifications** | Organization | Standard | Description | |---------------|----------------------|-------------------| | **AMS** | AMS 6514 | Steel Bars, Forgings, and Tubing 18Ni (300) | | **ASTM** | A538 | Standard Specification for Precipitation-Hardening Steel | | **UNS** | K93120 | Unified Numbering System Designation | | **MIL** | MIL-S-46850 | Steel, Maraging 300 Grade | | **ISO** | 683-13 | Heat-treatable steels, alloy steels, and free-cutting steels | --- #### **6. Heat Treatment Process** **Solution Annealing** - **Temperature:** 820 ± 10°C (1,508 ± 18°F) - **Time:** 1 hour per 25 mm of thickness - **Atmosphere:** Air or protective atmosphere - **Cooling:** Air cool to room temperature - **Resulting Hardness:** 32-36 HRC **Aging Treatment** - **Temperature:** 480 ± 5°C (896 ± 9°F) - **Time:** 3 - 8 hours (depending on section size) - **Cooling:** Air cool to room temperature - **Final Hardness:** 52-56 HRC --- #### **7. Fabrication & Machining** **Machining Recommendations** - **Annealed Condition:** Optimal for heavy machining (32-36 HRC) - **Tooling:** Carbide tools recommended for production - **Coolant:** Required for high-speed operations - **Aged Condition:** Grinding or EDM preferred **Welding Considerations** - **Weldability:** Good with proper procedures - **Processes:** TIG, MIG, and plasma arc welding suitable - **Filler Metal:** Matching composition recommended - **Pre/Post Heat Treatment:** Solution anneal after welding, age after all fabrication --- #### **8. Technical Advantages** **Key Benefits:** - **Ultimate Strength:** Highest strength in maraging steel family - **Excellent Strength-to-Weight Ratio:** Superior weight savings - **Good Toughness:** Maintains adequate fracture resistance - **Dimensional Stability:** Minimal distortion during aging - **Simple Heat Treatment:** No quenching required **Comparative Advantages:** - Higher strength than Maraging 250 and 200 grades - Better toughness than conventional ultra-high-strength steels - Superior performance in weight-critical applications - Proven reliability in extreme service conditions --- **Quality Assurance:** - Full traceability to melt source - Certified chemical and mechanical properties - Non-destructive testing available - Compliance with aerospace quality requirements **Contact Information:** [Your Company Information] *Note: All mechanical properties are typical for material in the fully aged condition. Actual properties may vary based on specific processing parameters and section size. Udimar 300 may have minor compositional variations optimized for specific applications. Consult technical data sheets for application-specific recommendations.*

Packing of Standard Packing: 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 2612 gallon liquid totes Special package is available on request.