DUPLEX STAINLESS STEEL, THIN SHEET MATERIAL AND DIAPHRAM USING DUPLEX STAINLESS STEEL

摘要

PROBLEM TO BE SOLVED: To provide a duplex stainless steel capable of achieving high strength, excellent in corrosion resistance and capable of providing smooth surface condition, and to provide a thin sheet material and a diaphram containing the duplex stainless steel.;SOLUTION: There is provided a duplex stainless steel having a composition of Cr:24 to 26 mass%, Mo:2.5 to 3.5 mass%, Ni:5.5 to 7.5 mass%, C≤0.03 mass%, N:0.08 to 0.3 mass% and the balance Fe with inevitable impurities and containing Mn:2.0 mass% or less as needed and having a particle diameter of inclusion particles consisting of Al oxide originated from inevitable impurity Al existing in a metal structure or Mn oxide of 3 μm or less. A diaphram 1 containing the duplex stainless steel has a dome part 2 with partial shell shape (dome shape) having a curvature radius which a central part is swollen and extruding to an upper side, and a collar part 4 serially formed on the peripheral edge of the dome part 2 via a boundary part 3.;COPYRIGHT: (C)2015,JPO&INPIT