Maraging 250,Maraging C250 Plate,UNS K92890,E FORU

British Specs:BS S162，American Specs:AMS 6512 Bar, Tube, Forgings AMS 6520 Sheet, Strip and Plate ASTM A646 MIL-S-46850 Type 3，German Specs:WS 1.6359

### **Product Datasheet: Maraging Steel 250 / Maraging C250 Plate (UNS K92890)** --- #### **1. Product Overview** **Maraging Steel 250 Plate** (commercially designated as **Maraging C250 Plate**, **UNS K92890**) is a flat-rolled product manufactured from ultra-high-strength maraging steel, designed for applications requiring exceptional strength and toughness in large surface areas. This product combines the superior mechanical properties of Maraging 250 alloy with the dimensional stability of plate manufacturing, providing optimal solutions for structural components, tooling applications, and defense systems where reliability and flatness are critical. The "C250" designation indicates commercial grade optimization for enhanced processability in plate forms. --- #### **2. Chemical Composition (Weight %)** | Element | Min (%) | Max (%) | Balance | |---------|----------|----------|---------| | **Nickel (Ni)** | 17.00 | 19.00 | - | | **Cobalt (Co)** | 7.00 | 8.50 | - | | **Molybdenum (Mo)** | 4.50 | 5.20 | - | | **Titanium (Ti)** | 0.30 | 0.50 | - | | **Aluminum (Al)** | 0.05 | 0.15 | - | | **Iron (Fe)** | - | - | Balance | | **Carbon (C)** | - | 0.03 | - | | **Manganese (Mn)** | - | 0.10 | - | | **Silicon (Si)** | - | 0.10 | - | | **Sulfur (S)** | - | 0.01 | - | | **Phosphorus (P)** | - | 0.01 | - | --- #### **3. Physical & Mechanical Properties** **A. Mechanical Properties (After Solution Annealing & Aging)** - **Tensile Strength:** 1,720 - 1,790 MPa (250 - 260 ksi) - **Yield Strength (0.2% Offset):** 1,655 - 1,725 MPa (240 - 250 ksi) - **Elongation:** 10 - 14% - **Reduction in Area:** 45 - 55% - **Hardness:** 48 - 52 HRC - **Fracture Toughness (K_Ic):** 70 - 90 MPa√m - **Impact Toughness (Charpy V):** 25 - 35 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:** 19.0 - 21.0 W/m·K - **Thermal Expansion Coefficient:** 10.5 - 11.0 × 10⁻⁶/°C (20 - 100°C) - **Electrical Resistivity:** 0.60 - 0.65 μΩ·m **C. Plate Specifications** - **Thickness Range:** 6 mm - 150 mm (0.25" - 6") - **Width Range:** 600 mm - 1,200 mm (24" - 48") - **Length Range:** 1,200 mm - 3,000 mm (48" - 120") - **Thickness Tolerance:** ±0.1 mm to ±0.5 mm - **Flatness:** ≤ 3 mm/m - **Surface Finish:** Hot-rolled, annealed, and descaled --- #### **4. Product Applications** **Aerospace & Defense** - **Rocket motor case** segments and bulkheads - **Aircraft structural** components and frames - **Missile launch** platform components - **Helicopter armor** plating systems - **Ordnance components** and protective structures **Tooling & Manufacturing** - **Precision mold** bases and cavity plates - **Die-casting** machine platens and die sets - **Injection molding** machine templates - **Fixture plates** and machine foundations - **Test equipment** structural frames **Industrial Applications** - **High-performance** racing components - **Hydraulic press** frames and components - **Nuclear reactor** internal components - **Marine applications** requiring corrosion resistance - **Special vehicle** armor and structural elements --- #### **5. International Standards & Specifications** | Standard Body | Specification Number | Title/Description | |---------------|----------------------|-------------------| | **AMS** | AMS 6512 | Steel Bars, Forgings, and Tubing 18Ni (250) | | **ASTM** | A538 | Standard Specification for Precipitation-Hardening Steel | | **ASTM** | A693 | Standard Specification for Precipitation-Hardening Stainless Steel Plate | | **UNS** | K92890 | Unified Numbering System Designation | | **MIL** | MIL-S-46850 | Steel, Maraging 250 Grade | | **ISO** | 683-13 | Heat-treatable steels, alloy steels, and free-cutting steels | --- #### **6. Heat Treatment Process** **Solution Annealing (Recommended before machining)** - **Temperature:** 820 ± 10°C (1,508 ± 18°F) - **Time:** 1 hour per 25 mm of thickness - **Atmosphere:** Protective atmosphere recommended - **Cooling:** Air cool to room temperature - **Resulting Hardness:** 28-32 HRC **Aging Treatment (After machining)** - **Temperature:** 480 ± 5°C (896 ± 9°F) - **Time:** 3-6 hours depending on plate thickness - **Cooling:** Air cool to room temperature - **Final Hardness:** 48-52 HRC **Special Considerations for Plate:** - Uniform heating and cooling essential - Proper support during heat treatment to prevent sagging - Temperature uniformity critical for large plates - Stress relieving available for critical applications --- #### **7. Machining & Fabrication** **Machining Guidelines:** - **Optimal Condition:** Machine in solution-annealed state - **Tooling:** Carbide tools with positive rake angles - **Speeds & Feeds:** Moderate speeds with adequate coolant - **Large Components:** Special fixturing may be required **Fabrication Advantages:** - **Minimal Distortion:** During age hardening process - **Good Machinability:** In annealed condition - **Weldability:** Excellent with proper procedures - **Stability:** Maintains flatness after heat treatment --- #### **8. Quality Assurance** **Standard Testing:** - **Chemical Analysis:** Certified ladle and product analysis - **Mechanical Testing:** Tensile and impact tests from representative locations - **Ultrasonic Testing:** Through-thickness examination - **Flatness Verification:** Optical measurement methods **Quality Certifications:** - **Material Traceability:** Full documentation provided - **Surface Quality:** Free from scale and harmful defects - **Dimensional Control:** Certified to specified tolerances - **Heat Treatment Certification:** When supplied in aged condition --- **Packaging & Delivery:** - Protective coating to prevent corrosion - Wooden crating for large plates - Clear identification and heat number marking - Custom cutting and machining services available **Contact Information:** [Your Company Information] *Note: All mechanical properties are typical for material in the fully aged condition. Properties may vary based on specific plate thickness and heat treatment parameters. Maraging C250 Plate offers enhanced consistency and performance for commercial plate applications. Consult our technical team for application-specific recommendations and processing guidance.*

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 2591 gallon liquid totes Special package is available on request.