Alloy 455，Custom 455 Plate，UNS S45500，EFORU

British Specs:，American Specs:AMS 5617 Bar and Forgings AMS 5860 Sheet, Strip and Plate，German Specs:

### **Alloy 455 / Custom 455 Plate (UNS S45500) - Product Introduction** **Overview** **Alloy 455**, commercially known as **Custom 455**, is a premium martensitic precipitation-hardening stainless steel that offers an exceptional combination of ultra-high strength, good corrosion resistance, and excellent toughness. **Custom 455 Plate** provides these superior properties in plate form, making it ideal for structural applications, armor systems, and high-stress components requiring maximum strength and reliability in demanding environments. The UNS **S45500** designation identifies this specific precipitation-hardening stainless steel composition. Custom 455 plate is particularly valued for applications requiring the highest strength-to-weight ratios, impact resistance, and good corrosion resistance comparable to standard austenitic stainless steels. --- ### **Chemical Composition** | Element | Content (%) | | :--- | :--- | | **Iron (Fe)** | Balance | | **Chromium (Cr)** | 11.0 - 12.5 | | **Nickel (Ni)** | 7.5 - 9.5 | | **Copper (Cu)** | 1.5 - 2.5 | | **Niobium (Nb)** | 0.1 - 0.5 | | **Titanium (Ti)** | 0.8 - 1.4 | | **Manganese (Mn)** | 0.50 (Max) | | **Silicon (Si)** | 0.50 (Max) | | **Carbon (C)** | 0.05 (Max) | | **Phosphorus (P)** | 0.04 (Max) | | **Sulfur (S)** | 0.03 (Max) | **Key Feature:** The balanced composition creates a precipitation-hardenable martensitic structure capable of achieving yield strengths exceeding 1450 MPa (210 ksi) after proper heat treatment, while maintaining good corrosion resistance. --- ### **Physical Properties** | Property | Value | | :--- | :--- | | **Density** | 7.76 g/cm³ (0.280 lb/in³) | | **Melting Point** | 1400-1440°C (2550-2625°F) | | **Electrical Resistivity** | 85 μΩ·cm at 20°C | | **Thermal Conductivity** | 18.5 W/m·K at 20°C | | **Thermal Expansion Coefficient** | 10.1 μm/m·°C (20-100°C) | | **Magnetic Permeability** | Magnetic after heat treatment | --- ### **Mechanical Properties** Typical mechanical properties for Custom 455 plate after heat treatment: | Condition | Tensile Strength | Yield Strength (0.2% Offset) | Elongation (%) | Hardness (Rockwell C) | | :--- | :--- | :--- | :--- | :--- | | **Solution Treated** | 1000-1200 MPa (145-175 ksi) | 950-1100 MPa (140-160 ksi) | 10-15 | 25-32 | | **H900 Aged** | 1550-1750 MPa (225-255 ksi) | 1450-1650 MPa (210-240 ksi) | 6-10 | 44-48 | | **H1000 Aged** | 1400-1600 MPa (200-230 ksi) | 1300-1500 MPa (190-220 ksi) | 8-12 | 40-44 | | **H1050 Aged** | 1250-1450 MPa (180-210 ksi) | 1150-1350 MPa (170-195 ksi) | 10-14 | 36-40 | --- ### **International Standards** | Standard Organization | Standard Number | Specification | | :--- | :--- | :--- | | **ASTM** | ASTM A693 | Precipitation Hardening Stainless and Heat-Resisting Steel Plate, Sheet, and Strip | | **AMS** | AMS 5606 | Steel Plate, Corrosion-Resistant, 12Cr - 9Ni - 1.5Cu - 1.0Ti | | **ASME** | SA-693 | Precipitation Hardening Stainless and Heat-Resisting Steel Plate, Sheet, and Strip | | **UNS** | S45500 | Alloy 455 | | **MIL-S** | MIL-S-23195 | Steel Plate, Alloy, Structural, High Yield Strength (140-180 ksi) | | **ASTM** | A666 | Standard Specification for Annealed or Cold-Worked Austenitic Stainless Steel Sheet, Strip, Plate, and Flat Bar | --- ### **Product Specifications** **Plate Specifications:** - **Thickness Range:** 0.187" to 4" (4.76mm to 101.6mm) - **Width Range:** 48" to 96" (1219mm to 2438mm) - **Length Range:** 96" to 480" (2438mm to 12192mm) - **Tolerances:** Standard mill tolerances or precision machining tolerances - **Surface Finish:** Hot rolled, annealed, pickled, or machined **Available Conditions:** - Solution Treated (Condition A) - Solution Treated and Aged (Various tempers) - Hot Rolled - Annealed - Stress Relieved --- ### **Heat Treatment** **Solution Treatment:** - Temperature: 815-830°C (1500-1525°F) - Time: 1 hour per inch of thickness - Cooling: Air cool or faster - Result: Soft condition for machining and forming **Aging Treatments:** - **H900:** 480°C (900°F) for 4 hours, air cool - **H950:** 510°C (950°F) for 4 hours, air cool - **H1000:** 540°C (1000°F) for 4 hours, air cool - **H1050:** 565°C (1050°F) for 4 hours, air cool --- ### **Product Applications** **Aerospace & Defense:** - Aircraft structural components - Missile and rocket body sections - Armor plating systems - Military vehicle components - Helicopter armor seats - Bullet-resistant applications **Industrial Equipment:** - High-strength machine bases - Press plates and die sets - Heavy-duty structural supports - Processing equipment components - Special tooling plates **Marine Applications:** - Shipbuilding components - Submarine structural parts - Offshore platform elements - Marine hardware - Naval vessel armor **Transportation:** - Armored vehicle components - Security vehicle applications - High-strength structural members - Protective systems **Special Applications:** - Nuclear component supports - High-stress fixture plates - Precision ground plates - Special machinery components --- ### **Fabrication Characteristics** **Machining:** - Best machined in solution-treated condition - Machinability rating: 45% (compared to 1212 steel) - Requires rigid setups and positive rake tools - Good surface finish achievable - Suitable for heavy machining operations **Forming:** - Can be formed in solution-treated condition - Good bendability in annealed state - Suitable for press brake operations - Requires attention to grain direction **Welding:** - **GTAW (TIG):** Preferred method - **GMAW (MIG):** Suitable with proper technique - **Filler Metal:** Custom 455 or similar PH stainless - **Post-weld Heat Treatment:** Required for maximum properties - **Pre-heat:** Generally not required --- ### **Key Advantages** - **Ultra-High Strength:** Highest strength available in plate form - **Excellent Toughness:** Good impact resistance at high strength levels - **Good Corrosion Resistance:** Superior to most martensitic stainless steels - **Outstanding Strength-to-Weight Ratio:** Ideal for weight-critical applications - **Dimensional Stability:** Minimal distortion during heat treatment - **Simple Heat Treatment:** Single-step aging process - **Versatile Fabrication:** Can be machined, formed, and welded **Design Considerations:** - Maximum service temperature: 425°C (800°F) - Suitable for cryogenic applications - Good resistance to stress corrosion cracking - Magnetic after heat treatment - Excellent ballistic properties in armor applications --- ### **Quality Assurance** **Testing and Certification:** - Chemical analysis certification - Mechanical testing verification - Ultrasonic testing - Hardness testing - Impact testing (when specified) - Dimensional verification **Certification Standards:** - ASTM A693 requirements - AMS 5606 specifications - Military standards (when applicable) - Customer-specific requirements - Full traceability documentation Custom 455 Plate (UNS S45500) represents a premium precipitation-hardening stainless steel in plate form that provides an outstanding combination of ultra-high strength, good corrosion resistance, and excellent mechanical properties. Its superior characteristics make it particularly valuable for aerospace, defense, marine, and high-performance industrial applications where maximum strength, impact resistance, and reliability are critical requirements in the most demanding service environments.

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 1694 gallon liquid totes Special package is available on request.