SPOT WELDED JOINT AND SPOT WELDING METHOD

摘要

The present invention is a spot welded joint formed by stacking a plurality of steel plates (1A, 1B) and spot welding. The cross tension strength of the spot welded joint formed is improved by obtaining a spot welded joint wherein at least one of the plurality of steel plates is a high-strength steel plate having a tensile strength of 750 (MPa) to 2500 (MPa), the carbon equivalent (Ceq) of the high-strength steel plate is 0.20 mass% to 0.55 mass%, and there are at least 10 iron carbides, in which the length of the longest section is at least 0.1 (µm), in a square region (103) within the heat-affected zone (4) of a cross section that passes through the center of the welding mark and is cut along the thickness direction of the steel plates (1A, 1B).