Spot welded joint and manufacturing method of spot welded joint

摘要

This spot welded joint includes a first steel plate, a second steel plate overlapping the first steel plate, and two spot welded metals joining the first steel plate and the second steel plate, wherein: in a cross section including the two spot welded metals, the first steel plate includes a first region formed between two spot welded metals in a zone of 0.1 mm in the thickness direction of the first steel plate from the surface on the second steel plate side, and a second region formed between the two spot welded metals in a zone of 0.1 mm in the thickness direction from the opposite surface to the surface on the second steel plate side; an average Vickers hardness HV1 in the first region and an average Vickers hardness HVbase of the first steel plate satisfy HVbase×0.33+150≤HV1≤HVbase×0.33+230; and an average Vickers hardness HV2 in the second region and the average Vickers hardness HVbase of the first steel plate satisfy HVbase-30≤HV2≤HVbase+30.