Resumen
A process for manufacturing an electrical steel sheet, the process comprising :a- providing a sheet of laminated electrical steel having a first and a second surface, a rolling direction or at least one easy magnetization direction(s), and a characteristic time for heat diffusion;b- forming a plurality of grooves on at least one of the first and second surfaces with at least one pass of a pulsed laser, each pass being associated with a scanning direction, the laser having a laser pulse repetition frequency, a pulse duration and emitting a light at a laser wavelength with a peak power density and a cumulative energy density per pass, the process being characterised in that :i) the laser pulse duration is equal to or less than a heat diffusion characteristic time of the electrical steel;ii) the peak power density is more than 50 TW/cm<sup>2</sup> or/ and the product between the peak power density and the pulse repetition frequency is more than 5000 TW/cm<sup>2</sup>/ms.iii) the cumulative energy density per laser pass is comprised between 10 J/cm<sup>2</sup> and 3500 J/cm<sup>2</sup>.