Alloy 725，Inconel 725 Bar(Round bar, Flat bar)，UNS N07725，EFORU

British Specs:，American Specs:ASTM B805，German Specs:

### **Product Introduction: Alloy 725 / Inconel 725 Bar (Round Bar, Flat Bar) UNS N07725** #### **Overview** **Alloy 725 Bar** (commercially known as **Inconel® 725 Bar**) is a premium precipitation-hardenable nickel-chromium-molybdenum-niobium alloy available in both round bar and flat bar configurations, specifically engineered for applications demanding exceptional corrosion resistance combined with high strength in severe environments. This advanced superalloy maintains outstanding performance in corrosive media including sour gas (H₂S-containing) wells, acidic environments, and chloride-containing solutions, while providing excellent mechanical properties at temperatures up to 650°C (1200°F). The bar products are manufactured through controlled thermo-mechanical processing and precise heat treatments to ensure uniform microstructure, consistent mechanical properties, and reliable performance in critical oil and gas, chemical processing, and marine applications. The alloy's enhanced characteristics are achieved through a sophisticated precipitation-hardening mechanism involving gamma prime [γ'] and gamma double prime [γ''] phase formation, providing an optimal balance of strength and corrosion resistance for demanding applications. --- #### **Chemical Composition** The chemical composition of Alloy 725 Bar (UNS N07725) is carefully balanced for optimal performance: | Element | Content (%) | | :--- | :--- | | **Nickel (Ni)** | 55.0 - 59.0 | | **Chromium (Cr)** | 19.0 - 22.5 | | **Molybdenum (Mo)** | 7.0 - 9.5 | | **Iron (Fe)** | 5.0 - 9.0 | | **Niobium (Nb)** | 2.75 - 4.00 | | **Titanium (Ti)** | 1.0 - 1.7 | | **Aluminum (Al)** | 0.35 - 0.75 | | **Manganese (Mn)** | ≤ 0.35 | | **Silicon (Si)** | ≤ 0.20 | | **Carbon (C)** | ≤ 0.03 | | **Sulfur (S)** | ≤ 0.010 | | **Copper (Cu)** | ≤ 0.20 | | **Phosphorus (P)** | ≤ 0.015 | *The optimized composition provides excellent corrosion resistance while enabling effective precipitation hardening through gamma double prime [γ'' Ni₃Nb] phase formation.* --- #### **Physical Properties** Critical properties for design and manufacturing engineering: | Property | Metric Value | Imperial Value | | :--- | :--- | :--- | | **Density** | 8.31 g/cm³ | 0.300 lb/in³ | | **Melting Range** | 1320 - 1360 °C | 2410 - 2480 °F | | **Specific Heat (20°C)** | 442 J/kg·K | 0.106 Btu/lb·°F | | **Thermal Conductivity (20°C)** | 10.8 W/m·K | 75.0 Btu·in/hr·ft²·°F | | **Thermal Expansion Coefficient (20-100°C)** | 12.9 μm/m·°C | 7.2 μin/in·°F | | **Modulus of Elasticity** | 206 GPa | 29.9 x 10⁶ psi | | **Electrical Resistivity** | 1.28 μΩ·m | - | --- #### **Mechanical Properties** Enhanced mechanical properties achieved through optimized heat treatment: **Solution Annealed + Aged Condition:** * **Ultimate Tensile Strength:** 1100-1240 MPa (160-180 ksi) * **Yield Strength (0.2% Offset):** 760-895 MPa (110-130 ksi) * **Elongation:** 15-25% * **Reduction of Area:** 35-50% * **Hardness:** 30-40 HRC **Elevated Temperature Performance:** * **0.2% Yield Strength at 205°C (400°F):** ≥ 690 MPa (100 ksi) * **Stress Rupture Life at 650°C (1200°F):** ≥ 100 hours at 310 MPa (45 ksi) * **Creep Resistance:** Excellent up to 650°C (1200°F) --- #### **International Standards** Alloy 725 Bar conforms to several international specifications: **ASTM Standards:** * **ASTM B805:** Precipitation Hardening Nickel Alloy Bars, Forgings, and Forging Stock * **ASTM B649:** Nickel-Iron-Chromium-Molybdenum-Columbium Stabilized Alloy Rod and Bar * **ASTM B670:** Plate, Sheet, and Strip (for flat bar products) **NACE Standards:** * **NACE MR0175/ISO 15156:** Suitable for use in H₂S-containing environments * **NACE MR0103:** Resistance to sulfide stress cracking **Other International Standards:** * **ISO 9724:** Nickel and Nickel Alloy Forgings * **DIN 17752:** Wrought Nickel and Nickel Alloys * **GB/T 15007:** Chinese Standard for Corrosion Resistant Alloys --- #### **Product Applications** **Round Bar Applications:** * **Oil & Gas:** Drill collars, valve stems, pump shafts, wellhead components * **Chemical Processing:** Agitator shafts, mixer components, reactor internals * **Marine Engineering:** Propeller shafts, rudder stocks, marine fasteners * **Power Generation:** Nuclear components, heat exchanger parts, structural elements **Flat Bar Applications:** * **Structural Components:** Support brackets, machine frames, structural reinforcements * **Tooling:** Fixtures, jigs, and specialized tool components * **Marine Construction:** Hull reinforcements, deck supports, marine structures * **Process Equipment:** Reactor internals, support frames, equipment bases **Specialized Applications:** * **Fastener Manufacturing:** High-strength bolts, studs, and special threaded components * **Machined Components:** Pump casings, valve bodies, bearing housings * **Welding Applications:** Base material for fabrication of corrosion-resistant equipment --- #### **Key Advantages** * **Exceptional Corrosion Resistance:** Superior performance in sour gas and chloride-containing environments * **High Strength:** Excellent mechanical properties maintained in corrosive conditions * **Outstanding Stress Corrosion Cracking Resistance:** Superior resistance to SCC in chloride environments * **Excellent Pitting Resistance:** High resistance to pitting and crevice corrosion * **Good Machinability:** Better machining characteristics compared to other corrosion-resistant superalloys * **Superior Fatigue Performance:** Excellent resistance to corrosion fatigue * **Weldability:** Good weldability with proper procedures and post-weld heat treatment * **Versatile Fabrication:** Suitable for machining, welding, and forming operations **Available Forms & Sizes:** * **Round Bar Diameters:** 5mm to 400mm (0.187" to 16") * **Flat Bar Sizes:** Thickness 5mm to 150mm (0.187" to 6"), Width up to 600mm (24") * **Surface Conditions:** Hot finished, turned, ground, or precision machined **Heat Treatment Specifications:** * **Solution Treatment:** 980-1010°C (1800-1850°F) followed by rapid cooling * **Aging Treatment:** 620-650°C (1150-1200°F) for 8-12 hours, air cool * **Double Aging:** Optional second aging at 590-620°C (1100-1150°F) for enhanced properties **Corrosion Performance:** * **Critical Pitting Temperature (ASTM G48):** > 85°C (185°F) * **Critical Crevice Temperature (ASTM G48):** > 65°C (150°F) * **Sulfide Stress Cracking:** Resistant per NACE MR0175 **Quality Assurance:** * **Ultrasonic Testing:** Detection of internal defects * **Chemical Analysis:** Complete composition verification * **Mechanical Testing:** Tensile, impact, and hardness testing * **Corrosion Testing:** Pitting, crevice, and stress corrosion cracking tests **Note:** *Inconel® is a registered trademark of Special Metals Corporation. Alloy 725 bars are typically supplied in the solution annealed condition for optimum machinability and formability, with subsequent aging treatment to develop the optimal combination of strength and corrosion resistance. The alloy demonstrates good weldability but requires proper post-weld heat treatment to restore corrosion resistance in the heat-affected zone. Comprehensive material certification including chemical analysis, mechanical properties, and corrosion testing reports are provided for critical applications.*

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 1808 gallon liquid totes Special package is available on request.