Weldability

Welding is possible by shielded metal arc welding, TIG welding, and plasma welding, in the same manner as with standard austenitic stainless steels. Alloy 276 welding consumables should be used. Preheating and post-heating are not required.

Machinability

As a distinctive feature of high Ni stainless steels, machining is difficult in comparison with standard austenitic stainless steels, but is easier than with Ni-based alloys. Cemented carbide cutting tools should be used if possible. Use of a slower feed rate in combination with greater cutting depth is recommended.

Heat Treatment

Solution annealing of UNS S32050 should be performed at 1150℃ and higher followed by being quenched in water or rapidly cooled by other means. (Conditions provided in ASTM A480/A480M)

Pickling

A mixed acid of nitric acid and hydrofluoric acid is used in pickling. Descaling is somewhat more difficult than with Type 304, corresponding to the higher corrosion resistance of UNS S32050. Before pickling, brief immersion in an alkaline solution, and if possible, shot blasting, is extremely effective for improving descaling.

Applications

Seawater environments: Seawater desalination systems, seawater heat exchangers, condenser tubes

High concentration chloride ion environments: Pulp and paper plant, various types of bleaching systems