A method for producing a magnetic inductor having a density greater than or equal to 99,9%, in a single-piece part including electrical and mechanical connection means, wherein said magnetic inductor comprises at least one inner channel that goes all along the length of the magnetic inductor and which is configured to channel a flow of refrigerating liquid inside it, wherein the method comprises using a system comprising an electron gun, a vacuum chamber, a working chamber and a manipulation system, characterized in that the method comprises the following phases: a. generating and accelerating an electron beam in the electron gun that comprises a cathode, an electrode and an anode; b. generating electrons when the cathode is heated up as the beam of electrons goes through it, and accelerating and directing said electrons to the pre-perforated and positively charged anode; c. depositing, pressing and flattening a layer of metal dust particles preheated at high temperatures between 350 and 700 degrees, where the metal dust particles comprise a conductive, non-magnetic material, selected between copper and copper-based alloy, having a spherical shape and a grain size between 40 and 100 μm, on top of a building surface of the vacuum chamber of the machine; d. selectively melting the metal dust particles by means of the electron beam, producing the required section, which at the same is welded to the previously produced section; e. lowering the building surface to the width required by means of a riser, creating a new layer repeating the steps a) to d), and the process starts again to complete the construction of the magnetic inductor; f. cleaning the remaining metal dust particles of the surface of the magnetic inductor; wherein: - the preheating temperature of the metal dust particles is selected between a range of 400 and 500 degrees for copper; - the acceleration voltage between the anode and the cathode is between 30 and 200 kV; - the intensity of the electron beam is between 0.5 and 1500 mA; - the diameter of the focus of the electron beam is between 0.25 and 1.5 mm; - the vacuum pressure is between 10 -5 mbar and 10 -3 mbar, and; - the power of the electron beam is between 50 and 3000W. a. generating and accelerating an electron beam in the electron gun that comprises a cathode, an electrode and an anode; b. generating electrons when the cathode is heated up as the beam of electrons goes through it, and accelerating and directing said electrons to the pre-perforated and positively charged anode; c. depositing, pressing and flattening a layer of metal dust particles preheated at high temperatures between 350 and 700 degrees, where the metal dust particles comprise a conductive, non-magnetic material, selected between copper and copper-based alloy, having a spherical shape and a grain size between 40 and 100 μm, on top of a building surface of the vacuum chamber of the machine; d. selectively melting the metal dust particles by means of the electron beam, producing the required section, which at the same is welded to the previously produced section; e. lowering the building surface to the width required by means of a riser, creating a new layer repeating the steps a) to d), and the process starts again to complete the construction of the magnetic inductor; f. cleaning the remaining metal dust particles of the surface of the magnetic inductor; - the preheating temperature of the metal dust particles is selected between a range of 400 and 500 degrees for copper; - the acceleration voltage between the anode and the cathode is between 30 and 200 kV; - the intensity of the electron beam is between 0.5 and 1500 mA; - the diameter of the focus of the electron beam is between 0.25 and 1.5 mm; - the vacuum pressure is between 10 -5 mbar and 10 -3 mbar, and; - the power of the electron beam is between 50 and 3000W.