The present disclosure inhibits liquid metal embrittlement (LME) cracking and improves corrosion resistance in a welded joint obtained by spot welding a first steel sheet and a second steel sheet. In the welded joint of the present disclosure, a first plating layer is provided on a surface of the first steel sheet facing the second steel sheet, no plating layer is present on or a second plating layer is provided on a surface of the second steel sheet facing the first steel sheet, a boundary plating layer is provided between the first steel sheet and the second steel sheet in a range of 0.5 mm from an end part of the corona bond of the spot welded part toward an outside of the spot welded part, and a Zn penetrated part is present at least at one of the first steel sheet and the second steel sheet adjoining the boundary plating layer. The Zn penetrated part advances from the boundary plating layer along the steel grain boundary, an Mg concentration at a front end of the Zn penetrated part at a location where a Zn concentration is 0.1 mass % is 0.20 mass % or less, and the first plating layer and the second plating layer satisfy a predetermined Relation I.
WELDED JOINT AND AUTOMOBILE MEMBER
2024-03-14
Patent
Electronic Resource
English
IPC: | F16B DEVICES FOR FASTENING OR SECURING CONSTRUCTIONAL ELEMENTS OR MACHINE PARTS TOGETHER, e.g. NAILS, BOLTS, CIRCLIPS, CLAMPS, CLIPS OR WEDGES , Vorrichtungen zum Befestigen oder Sichern von Konstruktionselementen oder Maschinenteilen, z.B. Nägel, Bolzen, Schrauben, Sprengringe, Klemmen, Klammern oder Keile / B23K Löten , SOLDERING OR UNSOLDERING / B62D MOTOR VEHICLES , Motorfahrzeuge |