| CPC B23K 11/115 (2013.01) [B23K 11/0026 (2013.01); B23K 11/241 (2013.01); B23K 2101/18 (2018.08)] | 12 Claims |

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1. A spot welding method for disposing a metal sheet laminate formed by laminating three or more metal sheets such that at least one metal sheet of the three or more metal sheets is thinner than the other metal sheets, between a pair of electrodes, and causing a pulse current to flow between the pair of electrodes to join the metal sheets, wherein
the pulse current is applied in a first current application step and a second current application step continuous with the first current application step, the second current application step having a period longer than a period of the first current application step, the first current application step and the second current application step each being performed using a DC chopping control method,
in the DC chopping control method, a pulse waveform of the pulse current is generated by switching between current application and current application stop to the pair of electrodes by a switching portion, and
a peak current value of the pulse current in the first current application step is set to a value equal to or larger than that of the pulse current in the second current application step, and an amount of power of the pulse current in the first current application step is set to a value larger than that of the pulse current in the second current application step.
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