Alloy-saving duplex stainless steel laser welded member with good laser weld characteristics and manufacturing method of alloy-saving duplex stainless steel laser welded member

摘要

PROBLEM TO BE SOLVED: To provide a lean duplex stainless steel laser-weld member in which difference between: property of a weld metal part and of a heat-affected zone; and property of a base metal.SOLUTION: The lean duplex stainless steel laser-weld member with good property of a laser weld part is provided in which a weld metal part is formed by welding a lean duplex stainless steel material having a predetermined chemical composition and area ratio of an austenite phase of 40% to 70% by a laser weld without using a filler metal, and in which the weld metal part has the austenite phase deposited on a grain boundary of a ferrite phase and having an average of width of a cross section of 2.5 μm or more, and the weld member has a calculated value of a deposition initiation temperature of Cr nitride Nof 1250°C or less. N=800 N-3Cr+20Si+10 Ni-4Mn+1140... (1). In the formula (1), Nrepresents nitrogen concentration (mass%) in the weld metal part and each element symbol represents content (mass%) of such element in the steel material.SELECTED DRAWING: None