Ohmic-heating printhead for 3D printer

A printhead for a 3D printer, said printhead comprising:

• two large walls parallel to each other and facing each other, and
• two small walls parallel to each other and facing each other, and perpendicular to the large walls,
• where the four walls define between them a cavity taking the form of a right-angled parallelepiped that extends between an inlet and an outlet that face each other and define between them a discharge direction,
• where each small wall is produced from an electrically non-conductive material,
• where, in the cavity, each large wall comprises a central wall and two lateral walls on either side of the central wall,
• where each lateral wall is produced from an electrically non-conductive material, and
• where the two central walls face each other, are produced from an electrically conductive material, and are intended to be electrically connected to an electricity generator that generates an alternating current and a difference in electrical potential between them.