ASTM B167 / ASME SB167 INCONEL ALLOY 600 / UNS NO6600 SEAMLESS TUBE

Overview

Inconel 600 is a nickel chromium alloy that exhibits excellent oxidation resistance at high temperatures and corrosion resistance in carburized and chloride containing environments. It is designed for low to high temperatures within the range of 2000 degrees Fahrenheit (1093 degrees Celsius). The high nickel content of this alloy allows it to maintain a considerable resistance under reducing conditions and resist the corrosion of many organic and inorganic compounds. The nickel content gives it excellent resistance to chloride ion stress corrosion cracking and excellent resistance to alkaline solutions. The chromium content gives the alloy the ability to resist sulfur compounds and various oxidation environments. The chromium content of this alloy makes it superior to commercial pure nickel under oxidation conditions. In strong oxidizing solutions such as high-temperature concentrated nitric acid, the resistance of 600 is very low. Alloy 600 is relatively resistant to most neutral and alkaline salt solutions and is used in certain corrosive environments. This alloy can resist steam and mixtures of steam, air, and carbon dioxide. Alloy 600 is non magnetic and has excellent mechanical properties, combined with high strength and good machinability, and is easy to weld. Chromium nickel iron alloy 600 has cold forming characteristics typically associated with chromium nickel stainless steel.

Corrosion Resistance

Inconel 600 has good corrosion resistance to many media. In feed water systems it is practically free of corrosion. It resists flowing sea water, but will corrode in stagnant sea water. The alloy has fair resistance to sulphuric acid at room temperature, but should not be used in this application at elevated temperatures. Resistance to hydrochloric acid is similar to sulphuric acid. The alloy has excellent resistance to phosphoric acid at room temperature in all concentrations, but is rapidly attacked at elevated temperature. Inconel 600 is practically free from chloride ion stress corrosion cracking. Please consult Austral Wright Metals for advice on your specific application.

Oxidation Resistance

Inconel 600 has good resistance to oxidation at high temperature. It out performs all other alloys for resistance to nitridation in cracked ammonia. It should not be used in sulphur containing atmospheres at high temperature, particularly if the conditions are reducing. It resists dry chlorine and hydrochloric acid gas at moderate temperatures.

Fabrication

Inconel 600 can be hot forged. The surface should be clean before heating. Solution annealing after forging is normal. Inconel 600 is readily cold formed by standard processes and equipment. Work hardening in cold forming may require intermediate anneal.

Machinability

Inconel 600 is reasonably easy to machine (class “C” alloy). Heavy machines, sharp tools, slow speeds and deep cuts to remove the work hardened layer are needed.

Weldability

Inconel 600 is readily welded by the SMAW (manual), GMAW (MIG), GTAW (TIG) and SAW processes. Preheat, post heat and post weld heat treatment are not needed. Contamination of the weld pool should be avoided. Inconel welding electrode 182 or Inconel filler metal 82 are normally used as welding consumables. Argon is used as the shielding gas.

Chemical Composition

Mechanical Properties

Equivalent Material

Applications:

• Aircraft ducting systems
• Aerospace
• Jet engine exhaust systems
• Engine thrust-reverser systems
• Specialized seawater equipment
• Chemical process equipment
• Chemical Processing
• Heat treating industry
• Power generation
• Heat treating muffles and retorts
• Radiant tubes
• Catalyst support grids in nitric acid production
• Steam superheater tube supports
• Pulp and paper industry
• Food processing
• Nuclear Engineering
• Gas turbine components