UNS N06625 (Inconel 625)
Generic Name & Other Designation
Inconel 625®, Alloy 625, Nickel Alloy 625,W.Nr. 2.4856, NiCr22Mo9Nb , NC22FeDN
Product Overview
UNS N06625 is a highly versatile nickel-chromium-molybdenum-niobium superalloy engineered for environments where severe mechanical stress coincides with highly corrosive chemical or marine conditions. Unlike age-hardenable alloys, Alloy 625 gains its high mechanical strength directly through solid-solution strengthening, allowing it to maintain excellent ductility and toughness without delicate thermal processing.
The alloy exhibits immunity to chloride-ion stress-corrosion cracking and resists a broad spectrum of aggressive media, including phosphoric acid, hydrofluoric acid, wet chlorine gas, and boiling nitric acid.
Key Highlights
✅ Solid-Solution Matrix Strengthening: Exceptional structural stability derived from the stiffening effect of molybdenum and niobium within a nickel-chromium matrix—eliminating the necessity for precipitation hardening heat treatments.
✅ Superior Resistance to Pitting & Crevice Attack: Outstanding resistance to severe localized corrosion and chloride-induced stress corrosion cracking, featuring a Pitting Resistance Equivalent Number (PREN) exceeding 45.
✅ Broad-Temperature Mechanical Integrity: Retains robust mechanical performance and fatigue resistance across operational conditions, ranging from cryogenic temperatures up to 982°C (1800°F).
✅ Exceptional Fabricability & Weldability: Easily formed and joined using standard welding processes (GTAW/GMAW) without post-weld cracking or loss of corrosion resistance in the heat-affected zone.
✅ Export-Ready Global Supply: Supplied directly by BELNADE with full traceabilty, custom conversion, and dual-certification to international specifications (ASTM, ASME, AMS, NACE).
Chemical Composition & Physical Properties
1. Chemical Composition (Weight %)
Element | Ni | Cr | Mo | Nb + Ta | Fe | Co | Mn | Si | Al | Ti | C | P | S |
Min. | 58.0 | 20.0 | 8.0 | 3.15 | — | — | — | — | — | — | — | — | — |
Max. | — | 23.0 | 10.0 | 4.15 | 5.0 | 1.0 | 0.50 | 0.50 | 0.40 | 0.40 | 0.10 | 0.015 | 0.015 |
- 2.Physical & Mechanical Attributes
Property | Value (Metric) | Value (Imperial) | Condition / Standard |
Density | 8.44 g/cm³ | 0.305 lb/in³ | — |
Melting Range | 1290°C – 1350°C | 2350°F – 2460°F | — |
Tensile Strength (Rm) | ≥ 760 MPa | ≥ 110 ksi | Grade 1 Annealed |
Yield Strength (Rp0.2) | ≥ 415 MPa | ≥ 60 ksi | Grade 1 Annealed |
Elongation (A5) | ≥ 30% | ≥ 30% | Grade 1 Annealed |
PREN | ≥ 45 | ≥ 45 | Pitting Resistance Equivalent No. |
Available Forms & Specifications
BELNADE maintains comprehensive inventory stocks and offers custom production runs across multiple mill product categories:
Seamless & Welded Piping: ASTM B444 / B705; OD 1/8″ to 24″, Schedules 10S through XXS.
Bar & Rod Products: ASTM B446; Round, hex, and square profiles from 6mm to 350mm diameter (ground, turned, or polished finishes).
Plate, Sheet & Strip: ASTM B443; Hot-rolled and cold-rolled configurations from 0.8mm to 75mm thickness.
Flanges & Pressure Fittings: ASTM B564; ANSI/ASME B16.5 Slip-On, Weld Neck, Blind, and Socket Weld flanges (150# through 2500# rating).
Typical Application Scenarios
The balanced chemical formulation of UNS N06625 makes it a primary material selection across diverse engineering sectors:
Marine & Offshore Engineering: Subsea cable sheathing, propulsion propellers, marine riser clamps, sonar domes, and seawater heat exchangers exposed to high velocity flow.
Chemical Processing Equipment: Reaction vessels, column tubing, flare stacks, acid production units, and transfer systems handling mixed acid streams.
Aerospace Ducting & Exhausts: Aircraft ducting systems, engine exhaust ducting, thrust reverser assemblies, and turbine shroud rings.
Pollution Control & Scrubbers: Flue gas desulfurization (FGD) scrubbers, reheaters, stack liners, and wet industrial scrubber systems.
Nuclear Energy: Core components and control rod shrouds operating in high-temperature pressurized water reactors.
Quality Assurance & Material Verification
Every shipment originating from BELNADE facilities undergoes stringent quality verification routines aligned with global procurement criteria:
Material Certification: Mill Test Certificates (MTC) supplied in strict accordance with EN 10204 Type 3.1 or 3.2.
Inspection Protocol:
Chemical Verification via OES and XRF Positive Material Identification (PMI)
Mechanical Property Evaluation (Tensile, Yield, Hardness, and Charpy Impact Testing)
Intergranular Corrosion Testing (ASTM G28 Method A/B)
Ultrasonic Flaw Detection (UT per ASTM A388/E213) and Hydrostatic Pressure Testing
Dimensional, Tolerance, and Surface Roughness Audits
Supplier Profile: BELNADE
BELNADE is a dedicated global distributor and exporter of high-performance nickel alloys, heat-resistant steels, and special stainless materials. We serve EPC contractors, original equipment manufacturers (OEMs), and fabricators worldwide with reliable material logistics and technical backing.
Streamlined Export Logistics: Rapid dispatch from stock, container loading oversight, export packing (seaworthy wooden cases), and full documentation for air/sea freight.
Processing & Pre-Machining Capabilities: Precision band-saw cutting, CNC plate beveling, waterjet profile cutting, and custom length conversion.
Metallurgical Technical Consultation: Technical assistance on grade selection, NACE compliance matching, and welding procedure specification (WPS) support.
Partner with BELNADE for High-Grade Alloy Solutions
📧 Email: info@belnade-material.com
🌐 Website: www.belnade-material.com
💬 Mobile/ WhatsApp: +86 158-0040-6687