WELDING METHOD FOR FLUX-CORED WIRE FOR GAS SHIELD ARC WELDING AND CRYOGENIC TEMPERATURE COPPER AND MANUFACTURING METHOD FOR WELDING JOINT

摘要

PROBLEM TO BE SOLVED: To provide a flux-cored wire which can provide a weld metal having excellent low-temperature toughness, has a high welding execution efficiency, and enables the omission or simplification of preheating executed for suppressing cold cracks.;SOLUTION: This flux-cored wire contains one or two or more kinds of CaF₂, BaF₂, SrF₂, MgF₂, and LiF. When a total amount of their contents is α, the α is 2.0-7.0% by mass% to the total mass of the flux-cored wire and contains one or two or more kinds of Ti oxide, Si oxide, Mg oxide, Al oxide, Zr oxide and Ca oxide. When a total amount of their contents is β, the β is 0.2-0.9% by mass% to the total mass of the flux-cored wire. A ratio of the CaF₂ content to the α is 0.90 or more, and a ratio of the α to the β is 3.0 or more and 15.0 or less.;COPYRIGHT: (C)2015,JPO&INPIT