Abstract: A manufacturing method for manufacturing a separator for a fuel cell includes a step of applying a laser beam to a surface of a plate-shaped metal plate having a rectangular shape such that an application range of the laser beam extends linearly. In the step, the laser beam is applied such that the application range includes a high-energy region in which energy to be given by the laser beam per unit distance in a direction where the application range extends linearly is high, and a low-energy region in which the energy is low. The high-energy region includes a first region, a second region, a third region, and a fourth region. The first region and the second region extend in parallel to one of long sides of the rectangular shape. The third region and the fourth region extend in parallel to the other one of the long sides.

Abstract: A manufacturing method for manufacturing a separator for a fuel cell includes a step of applying a laser beam to a surface of a plate-shaped metal plate having a rectangular shape such that an application range of the laser beam extends linearly. In the step, the laser beam is applied such that the application range includes a high-energy region in which energy to be given by the laser beam per unit distance in a direction where the application range extends linearly is high, and a low-energy region in which the energy is low. The high-energy region includes a first region, a second region, a third region, and a fourth region. The first region and the second region extend in parallel to one of long sides of the rectangular shape. The third region and the fourth region extend in parallel to the other one of the long sides.