| 摘要 |
Resistance spot welding is performed on a combination of overlapping steel sheets including at least one steel sheet that has, on a surface thereof, a coated layer with zinc as a main component, by (1) starting electric current passage in a state satisfying 0.9 × t ‰¤ L ‰¤ 1.1 × t, where t is the total thickness of the overlapping steel sheets and L is the distance between tips of upper and lower electrodes; and (2) dividing electric current into main current and initial current that precedes the main current and is two-step current, setting a current value I 1 during current in a first step of the initial current to satisfy I m × 1.1 ‰¤ I 1 ‰¤ 15.0 kA with respect to a current value I m during the main current, and setting a current value I 2 in the subsequent second step to no current or low current satisfying 0 ‰¤ I 2 ‰¤ I m × 0.7, thereby stably forming a nugget of sufficient diameter, without the occurrence of splashing. |
