Inconel 625 (UNS N06625)

Inconel 625 (also specified as UNS N06625 / Werkstoff No. 2.4856 / NCF 625) is a nickel-chromium-molybdenum-niobium solid-solution strengthened superalloy. Its combination of high strength, excellent fabricability and outstanding corrosion resistance makes it one of the most widely used general-purpose advanced nickel alloys, with particular strength in chloride pitting / crevice corrosion resistance and cryogenic-to-moderately-high-temperature service.

Overview

• Category: Ni-Cr-Mo-Nb solid-solution strengthened nickel alloy
• Standards: ASTM B443, ASME SB-443, AMS 5666, AMS 5667, UNS N06625, DIN/EN 2.4856, JIS NCF 625
• Available forms: Round bar / rod, plate, sheet, strip, pipe & tube, wire, forgings, and custom profiles to order

Chemical Composition (wt%)

Physical Properties

Mechanical Properties (typical, solution-annealed)

Fabrication & Welding

• Hot working: 1000–1230 °C; cool rapidly after hot working to preserve properties.
• Cold working: Good cold-formability; readily cold-drawn and cold-rolled.
• Welding: Excellent weldability by GTAW (TIG), GMAW (MIG), SMAW (MMA) and other conventional processes.

Heat Treatment

• Solution treatment: Heat to 1093–1204 °C and cool rapidly, to obtain a uniform austenitic microstructure and maximise corrosion resistance and toughness.
• Stress-relief annealing: Heat to 704–816 °C and air-cool, to relieve residual stresses introduced during fabrication.

Key Features

• Excellent corrosion resistance in seawater, chemical process media, various acids and oxidising / reducing environments;
• Good high-temperature strength and oxidation resistance, retaining strength and stability at elevated temperature;
• Outstanding fatigue and creep-rupture performance;
• Good formability and weldability.

Corrosion Resistance

• Superior resistance to sulfuric, hydrochloric, nitric and phosphoric acids over a wide range of concentrations;
• Strong resistance to pitting and crevice corrosion in marine and chloride-bearing environments;
• Good resistance to stress-corrosion cracking and to reducing-acid service.

Typical Applications

• Aerospace: engine components and airframe structural parts;
• Marine engineering: piping, valves and connectors on offshore platforms;
• Petrochemical: reaction vessels, heat exchangers and process piping systems;
• Automotive: high-performance engine components;
• Power generation: gas-turbine parts and nuclear-reactor internals.

For detailed datasheets, mill certificates (EN 10204 3.1) or inquiries on specific sizes and tolerances, please contact our sales & engineering team.