Maraging 300,Udimar 300 Bar(Round bar, Flat bar),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 Bar (Round & Flat Bar) UNS K93120** --- #### **1. Product Overview** **Maraging Steel 300 Bar** (commercially known as **Udimar 300 Bar**, **UNS K93120**) is supplied in both round bar and flat bar configurations, providing versatile stock material for manufacturing critical components requiring the highest strength-to-weight ratio in the maraging steel family. This product combines the exceptional mechanical properties of Maraging 300 alloy with excellent dimensional stability, making it ideal for aerospace, defense, and tooling applications where maximum strength and reliability are paramount. --- #### **2. Chemical Composition (Weight %)** | Element | Min (%) | Max (%) | Function | |---------|----------|----------|----------| | **Nickel (Ni)** | 18.00 | 19.00 | Matrix strengthening | | **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 | | **Aluminum (Al)** | 0.05 | 0.15 | Secondary age-hardening | | **Carbon (C)** | - | 0.03 | Impurity control | | **Iron (Fe)** | - | - | Balance | --- #### **3. Mechanical & Physical Properties** **A. Mechanical Properties (Aged Condition)** - **Tensile Strength:** 2,000-2,140 MPa (290-310 ksi) - **Yield Strength:** 1,930-2,070 MPa (280-300 ksi) - **Elongation:** 8-10% - **Reduction in Area:** 40-50% - **Hardness:** 52-56 HRC - **Fracture Toughness:** 50-70 MPa√m - **Impact Toughness:** 15-25 J **B. Physical Properties** - **Density:** 8.00 g/cm³ - **Modulus of Elasticity:** 185 GPa - **Thermal Conductivity:** 18.0-20.0 W/m·K - **Thermal Expansion:** 10.4-10.9 × 10⁻⁶/°C --- #### **4. Product Specifications** **Round Bar:** - **Diameter Range:** 5-300 mm (0.2-12 inches) - **Diameter Tolerance:** h11 standard - **Straightness:** ≤ 1.5 mm/m - **Surface Finish:** Turned, ground, or polished **Flat Bar:** - **Thickness Range:** 5-150 mm (0.2-6 inches) - **Width Range:** 20-300 mm (0.8-12 inches) - **Thickness Tolerance:** ±0.1 to ±0.5 mm - **Squareness:** Maintained within 1° **Available Conditions:** - Annealed (32-36 HRC) - Aged (52-56 HRC) - Solution Treated --- #### **5. Applications** **Round Bar Applications:** - Aircraft landing gear actuators - Rocket motor closures - Precision shafts and spindles - High-strength fasteners - Die-casting machine components **Flat Bar Applications:** - Aircraft structural brackets - Tooling plates and mold bases - Machine frames and fixtures - Defense vehicle structural members - Precision ground stock **Common Applications:** - Injection molding components - Extrusion press components - Helicopter rotor systems - Racing engine components - Optical mounting instruments --- #### **6. Standards & Specifications** | Organization | Standard | Description | |--------------|----------|-------------| | **AMS** | 6514 | Bars, Forgings, and Tubing | | **ASTM** | A538 | Grade 300 | | **UNS** | K93120 | Unified Numbering System | | **MIL** | S-46850 | Maraging Steel Grade 300 | --- #### **7. Heat Treatment Process** **Solution Annealing:** - **Temperature:** 820 ± 10°C (1,508 ± 18°F) - **Time:** 1 hour per 25 mm thickness - **Cooling:** Air cool - **Hardness:** 32-36 HRC **Aging Treatment:** - **Temperature:** 480 ± 5°C (896 ± 9°F) - **Time:** 3-8 hours - **Cooling:** Air cool - **Hardness:** 52-56 HRC --- #### **8. Machining & Fabrication** **Machining Guidelines:** - **Optimal Condition:** Annealed state (32-36 HRC) - **Tooling:** Carbide tools recommended - **Coolant:** Required for optimal results - **Threading:** Excellent with proper tooling **Fabrication Advantages:** - Minimal distortion during aging - Good machinability in annealed condition - Excellent weldability with proper procedures - Maintains dimensional stability --- #### **9. Quality Assurance** **Testing & Certification:** - Chemical analysis certification - Mechanical testing from samples - Ultrasonic testing available - Dimensional verification - Full traceability documentation **Quality Standards:** - Aerospace quality (AS9100) - Nadcap accredited - Military compliance - Statistical process control --- **Packaging & Delivery:** - Protective packaging - Clear identification marking - Custom cutting services - Just-in-time delivery available **Contact:** [Your Company Information] *Note: All mechanical properties are typical for material in the fully aged condition. Properties may vary based on specific section size and heat treatment parameters. Consult our technical team 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 2614 gallon liquid totes Special package is available on request.