MP35N,MP35N,UNS R30035,E FORU

### **MP35N® / UNS R30035** **Cobalt-Nickel-Chromium-Molybdenum Alloy with Ultra-High Strength and Corrosion Resistance

** --- #### **1. Overview

** **MP35N** is a unique cobalt-nickel-chromium-molybdenum alloy renowned for its exceptional combination of ultra-high strength, excellent corrosion resistance, and non-magnetic properties. The alloy achieves its remarkable mechanical properties through a specialized thermomechanical processing sequence that induces multiphase strengthening. MP35N exhibits outstanding performance in the most demanding applications, maintaining its properties across a wide temperature range from cryogenic conditions up to 425°C (800°F). Its unique ability to develop extremely high strength while maintaining excellent corrosion resistance makes it invaluable for critical applications in aerospace, medical, and marine industries. 

 --- #### **2. Chemical Composition (Weight %)

** The typical chemical composition of MP35N is outlined below. 

| Element | Content (%) | Key Function | 

| :--- | :--- | :--- | 

| **Cobalt (Co)** | 35.0 | Base element providing the fundamental matrix and solid-solution strength. | 

| **Nickel (Ni)** | 35.0 | Stabilizes the austenitic phase and enables phase transformation strengthening. | 

| **Chromium (Cr)** | 20.0 | Provides outstanding corrosion resistance through passive film formation. | 

| **Molybdenum (Mo)** | 10.0 | Enhances strength and improves resistance to pitting and crevice corrosion. | 

| **Titanium (Ti)** | 1.0 max | Optional addition for enhanced strengthening in specific processing routes. | 

| **Manganese (Mn)** | 0.15 max | Controlled impurity. | | **Silicon (Si)** | 0.15 max | Controlled impurity. | 

| **Iron (Fe)** | 1.0 max | Controlled impurity. | 

| **Carbon (C)** | 0.025 max | Kept low to maintain corrosion resistance and formability. | 

| **Boron (B)** | 0.015 max | Enhances grain boundary strength. | 

 --- #### **3. Physical Properties** 

| Property | Value / Condition | 

| :--- | :--- | 

| **Density** | 8.43 g/cm³ (0.304 lb/in³) | 

| **Melting Range** | ~ 1315 - 1440 °C (2400 - 2625 °F) | 

| **Mean Coefficient of Thermal Expansion** | 20 - 400°C (68 - 750°F): **12.8 x 10⁻⁶/°C** (7.1 x 10⁻⁶/°F) | 

| **Thermal Conductivity** | 11.7 W/m·K (81 Btu·in/hr·ft²·°F) at 21°C (70°F) | | **Specific Heat** | 425 J/kg·K (0.102 Btu/lb·°F) at 21°C (70°F) | 

| **Electrical Resistivity** | 1.02 μΩ·m at 21°C (70°F) | 

| **Modulus of Elasticity (Young's Modulus)** | 238 GPa (34.5 x 10⁶ psi) at 21°C (70°F) | 

| **Magnetic Permeability** | Essentially non-magnetic (μ < 1.005) | 

 --- #### **4. Mechanical Properties

 (Typical for Cold Worked + Aged Condition)** 

| Property | At Room Temperature | At 315°C (600°F) | At 425°C (800°F) | 

| :--- | :--- | :--- | :--- | 

| **Tensile Strength** | 1950 - 2275 MPa (283 - 330 ksi) | 1655 - 1930 MPa (240 - 280 ksi) | 1380 - 1655 MPa (200 - 240 ksi) | 

| **Yield Strength (0.2% Offset)** | 1790 - 2070 MPa (260 - 300 ksi) | 1515 - 1790 MPa (220 - 260 ksi) | 1240 - 1515 MPa (180 - 220 ksi) | 

| **Elongation (in 50 mm / 2 in)** | 8 - 12% | 10 - 15% | 12 - 18% | 

| **Reduction of Area** | 35 - 50% | 40 - 55% | 45 - 60% | 

| **Hardness (Rockwell C)** | 50 - 55 HRC | - | - | 

 --- #### **5. International Standards** 

 MP35N is covered by the following international specifications: 

 *   **ASTM:**    

*   **F562:** Standard Specification for Wrought Cobalt-35Nickel-20Chromium-10Molybdenum Alloy 

*   **AMS:**   

*   **AMS 5759:** Bar and Forging Stock    

*   **AMS 5844:** Wire for Springs and Fasteners 

*   **ISO:**    

*   **ISO 5832-6:** Implants for surgery - Metallic materials 

*   **UNS:** R30035 

*   **Aerospace Standards:

**    *   **NASM:** National Aerospace Standard Materials 

 --- #### **6. Product Applications

** MP35N serves critical functions in the most demanding applications: 

 *   **Aerospace & Defense:**    

*   Aircraft engine components    

*   High-strength fasteners and bolts    

*   Landing gear components    

*   Helicopter rotor pins 

*   **Medical Devices:

**    *   Orthopedic implants    

*   Surgical instruments    

*   Pacemaker leads    

*   Dental implants 

*   **Marine & Offshore:

**    *   Subsea fasteners    

*   Marine hardware    

*   Offshore platform components 

*   **Oil & Gas:

**    *   Downhole tools    

*   Well completion equipment    

*   High-strength corrosion-resistant components 

 --- #### **7. Key Characteristics & Advantages

** *   **Ultra-High Strength:

** Exceptional strength-to-weight ratio 

*   **Outstanding Corrosion Resistance:

** Excellent performance in chloride environments and seawater 

*   **Non-Magnetic Properties:

** Essential for MRI and other sensitive applications 

*   **Excellent Fatigue Resistance:

** Superior performance under cyclic loading 

*   **Good Biocompatibility:

** Suitable for long-term medical implants 

*   **Wide Temperature Capability:

** Maintains properties from cryogenic to elevated temperatures 

*   **Unique Strengthening Mechanism:

** Multiphase transformation enables extraordinary strength development 

 --- **Disclaimer:

** *MP35N® is a registered trademark of SPS Technologies, Inc. The values provided are typical and for informational purposes only. For critical applications, especially in aerospace and medical fields, always consult the official material data sheets from the supplier and relevant design codes. MP35N requires specialized thermomechanical processing to achieve its optimal properties.*

Packing of MP35N,MP35N,UNS R30035

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 1672 gallon liquid totes Special package is available on request.