Alloy 725，Inconel 725 Strip，UNS N07725，EFORU

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

### **Product Introduction: Alloy 725 / Inconel 725 Strip (UNS N07725)** #### **Overview** **Alloy 725 Strip** (commercially known as **Inconel® 725 Strip**) is a precision-rolled nickel-chromium-molybdenum-niobium alloy supplied in thin, narrow coil form, specifically engineered for applications requiring exceptional corrosion resistance combined with high strength in severe environments. This precipitation-hardenable alloy strip maintains outstanding performance in corrosive media including sour gas (H₂S-containing) wells, acidic solutions, and chloride-containing environments, while providing excellent mechanical properties at temperatures up to 650°C (1200°F). The strip product undergoes sophisticated cold rolling and controlled heat treatment processes to achieve exact gauge control, superior surface finish, and consistent mechanical properties essential for high-precision components in 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 precision applications. --- #### **Chemical Composition** The chemical composition of Alloy 725 Strip (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 precision component design and manufacturing: | 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 tailored for strip applications: **Annealed Condition (Formable):** * **Tensile Strength:** 900-1050 MPa (130-152 ksi) * **Yield Strength:** 550-700 MPa (80-102 ksi) * **Elongation:** 25-35% **Precipitation Hardened Condition:** * **Tensile Strength:** 1100-1240 MPa (160-180 ksi) * **Yield Strength:** 760-895 MPa (110-130 ksi) * **Elongation:** 15-25% * **Hardness:** 30-38 HRC * **Flatness:** ≤ 1% of strip width --- #### **International Standards** Alloy 725 Strip conforms to several international specifications: **ASTM Standards:** * **ASTM B670:** Plate, Sheet, and Strip for High-Temperature Service * **ASTM B906:** General Requirements for Flat-Rolled Nickel and Nickel Alloys **NACE Standards:** * **NACE MR0175/ISO 15156:** Suitable for use in H₂S-containing environments * **NACE MR0103:** Resistance to sulfide stress cracking **Other International Standards:** * **ISO 6208:** Nickel and nickel alloy strip * **DIN 17750:** Nickel and nickel alloy strip - Technical delivery conditions * **GB/T 2054:** Chinese standard for nickel and nickel alloy strip --- #### **Product Applications** Alloy 725 strip serves critical functions in precision component manufacturing: **Oil & Gas Industry:** * **Sealing Elements:** Gaskets, seal strips for sour service applications * **Spring Components:** High-corrosion resistance springs, bellows * **Instrumentation:** Sensor components, diaphragm elements * **Fastening Systems:** Special washers, retaining rings, corrosion-resistant fasteners **Chemical Processing:** * **Seal Strips:** Reactor seal components, vessel closure strips * **Spring Contacts:** Corrosive environment electrical contacts * **Filter Elements:** Wire mesh for corrosive filtration * **Valve Components:** Precision valve springs, seal retainers **Marine & Offshore:** * **Marine Components:** Corrosion-resistant springs, marine fastener strips * **Offshore Equipment:** Control system components, sensor strips * **Desalination Plants:** Filter screen wire, spring elements **Electronics & Electrical:** * **Connector Components:** High-rel electrical contacts for corrosive environments * **Spring Contacts:** Test socket springs, battery contacts * **Shielding Components:** EMI/RFI shielding elements --- #### **Key Advantages** * **Precision Gauge Control:** Exceptional thickness consistency (±0.005mm) * **Exceptional Corrosion Resistance:** Superior performance in sour gas and chloride-containing environments * **Superior Surface Quality:** Various finishes available (2B, BA, polished) * **Excellent Formability:** Suitable for stamping, bending, and deep drawing * **Outstanding Spring Properties:** High yield strength and elastic modulus * **Excellent Pitting Resistance:** High resistance to pitting and crevice corrosion * **Stress Corrosion Cracking Resistance:** Superior resistance to SCC in chloride environments * **Fatigue Resistance:** Excellent performance under cyclic loading conditions **Available Forms & Sizes:** * **Thickness Range:** 0.05mm to 2.0mm (0.002" to 0.080") * **Width Range:** 2mm to 600mm (0.080" to 24") * **Coil Weights:** Standard and custom coil sizes available * **Temper Conditions:** Annealed, 1/4 hard, 1/2 hard, full hard, aged **Processing Capabilities:** * **Precision Slitting:** Tight width tolerances (±0.025mm) * **Edge Conditioning:** Round, square, or custom edge profiles * **Surface Treatment:** Passivation, cleaning, special coatings * **Heat Treatment:** Precise thermal processing for property optimization **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:** * **Dimensional Verification:** 100% thickness and width monitoring * **Surface Inspection:** Visual and automated surface quality control * **Mechanical Testing:** Tensile, hardness, and spring property testing * **Corrosion Testing:** Pitting, crevice, and stress corrosion cracking tests **Note:** *Inconel® is a registered trademark of Special Metals Corporation. Alloy 725 strip is typically supplied in the annealed condition for optimum formability, with subsequent aging treatment (620-650°C/1150-1200°F for 8-12 hours) to develop the optimal combination of strength and corrosion resistance. Special processing including precision slitting, edge conditioning, and specific heat treatments are available to meet exact application requirements. Proper handling and storage in controlled environments are recommended to maintain surface quality and performance characteristics. Comprehensive certification packages are provided for all 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 1813 gallon liquid totes Special package is available on request.