Alloy X750,Inconel X750,UNS N07750,EFORU

### **Technical Datasheet: Alloy X-750 (Inconel X-750, UNS N07750)** 

 **Introduction** Alloy X-750 is a precipitation-hardenable nickel-chromium alloy known for its high strength and excellent corrosion resistance at temperatures up to about 700°C (1300°F). It is derived from the iconic Alloy 600 (Inconel 600) but is strengthened by the addition of aluminum and titanium, which form the gamma prime [Ni₃(Al, Ti)] precipitate during age-hardening heat treatment. A long-established and versatile superalloy, Alloy X-750 is widely used in aerospace, nuclear, and industrial applications for its reliable performance and good fabrication characteristics. 

### **Technical Datasheet: Alloy X-750 (Inconel X-750, UNS N07750)** 

 **Introduction** Alloy X-750 is a precipitation-hardenable nickel-chromium alloy known for its high strength and excellent corrosion resistance at temperatures up to about 700°C (1300°F). It is derived from the iconic Alloy 600 (Inconel 600) but is strengthened by the addition of aluminum and titanium, which form the gamma prime [Ni₃(Al, Ti)] precipitate during age-hardening heat treatment. A long-established and versatile superalloy, Alloy X-750 is widely used in aerospace, nuclear, and industrial applications for its reliable performance and good fabrication characteristics. 

 **Key Features** *   

**High Strength at Elevated Temperatures:

** Maintains excellent tensile, creep, and rupture strength up to 700°C (1300°F). *   

**Good Corrosion and Oxidation Resistance:

** Resists a wide variety of corrosive environments and exhibits excellent oxidation resistance. *   

**Excellent Relaxation Resistance:** Ideal for high-temperature springs and fasteners that must maintain load under stress. *   

**Good Fabricability:

** Can be readily formed, machined, and welded using standard methods for high-temperature alloys. 

1. Chemical Composition (Weight %)** The typical composition of Alloy X-750 is specified in various international standards. The following is a representative range:

| Element | Minimum (%) | Maximum (%) | 

| :--- | :--- | :--- | 

| **Nickel (Ni)** | 70.0 | 73.0 | 

| **Chromium (Cr)** | 14.0 | 17.0 | 

| **Iron (Fe)** | 5.0 | 9.0 | 

| **Titanium (Ti)** | 2.25 | 2.75 | 

| **Aluminum (Al)** | 0.40 | 1.00 | 

| **Niobium (Nb) + Tantalum (Ta)** | 0.70 | 1.20 | 

| **Cobalt (Co)** | - | 1.00 | 

| **Carbon (C)** | - | 0.08 | 

| **Manganese (Mn)** | - | 1.00 | 

| **Silicon (Si)** | - | 0.50 | 

| **Copper (Cu)** | - | 0.50 | 

| **Sulfur (S)** | - | 0.010 | 

 *The primary strengthening mechanism is precipitation hardening via the gamma prime (γ') phase [Ni₃(Al,Ti)].*

2. Physical Properties

 | Property | Value | 

| :--- | :--- |

| **Density** | 8.28 g/cm³ (0.299 lb/in³) | 

| **Melting Range** | ~ 1390 - 1430 °C (~ 2530 - 2600 °F) | 

| **Specific Heat (20°C)** | ~ 431 J/kg·K | 

| **Thermal Conductivity (20°C)** | ~ 12.0 W/m·K | 

| **Mean Coefficient of Thermal Expansion (20-100°C)** | ~ 12.8 µm/m·°C | 

| **Modulus of Elasticity (Young's Modulus)** | ~ 214 GPa (31.0 x 10⁶ psi) | 

3. Mechanical Properties (Typical for Solution Annealed & Aged Condition)

** Properties can vary significantly with the specific heat treatment cycle (e.g., AH, HTH, SHT). The following are typical minimums for bar products. 

 **Room Temperature (Aged Condition):** *   

**Tensile Strength:** ≥ 1035 MPa (150 ksi) *   

**Yield Strength (0.2% Offset):** ≥ 690 MPa (100 ksi) *   

**Elongation:** ≥ 20% **At 650°C (1200°F):** *   

**Tensile Strength:** ~ 790 MPa (115 ksi) *   

**Yield Strength (0.2% Offset):** ~ 655 MPa (95 ksi) 

4. International Standards** 

 Alloy X-750 is covered by a wide range of international specifications, particularly in aerospace and nuclear industries.

 | Product Form | Standard Examples | 

| :--- | :--- | 

| **Bar, Wire, Forgings** | **AMS 5667** (Bars, Forgings), **AMS 5670** (Spring Wire), **ASTM B637** | 

| **Plate, Sheet, Strip** | **AMS 5542** (Sheet, Strip, Plate), **ASTM B168** | 

| **Tubing** | **ASTM B637** | 

| **Fasteners** | **AMS 5731**, **AMS 5732** | 

| **European Standard** | **EN: NiCr15Fe7TiAl** | 

| **Unified Numbering System** | **UNS N07750** | 

5. Product Applications** 

 Alloy X-750 is a versatile alloy used in critical high-strength and high-temperature applications across several industries. *   

**Aerospace & Jet Engines:**    *   

**Turbine Blades** and **Disks**    *   

**Engine Mounts** and **Structural Components**    *   

**Fasteners**, **Bolts**, and **Studs**    *   

**Springs** and **Seals** *   

**Nuclear Power Industry:**    *   

**Reactor Core Components** (e.g., spider hubs, support pins, seal plates)    *   

**Fuel Assembly Hardware**    *   

**Springs** for nuclear fuel channels *   

**Industrial Gas Turbines:**    *   

**Blades**, **Buckets**, and **Rings**    *   

**Fasteners** for hot sections *   

**Other Applications:**    *   

**Hot-work tooling** and **die inserts**    *   

**Bellows** and **expansion joints**    *   

**Test machine components** requiring high strength and stability --- 

 **Conclusion** 

Alloy X-750 (Inconel X-750, UNS N07750) is a time-tested, high-performance nickel-based superalloy that continues to be a critical material for applications demanding a reliable combination of high strength, good fabricability, and resistance to corrosion and oxidation. Its well-understood properties and behavior under various heat treatments have secured its place as a fundamental material in the aerospace, nuclear, and power generation sectors for decades.

Packing of Alloy X-750 (Inconel X-750, UNS N07750) 

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 1639 gallon liquid totes Special package is available on request.