Method for producing components for motor-vehicle structures, having a hybrid structure made of light alloy and plastic material

A component of a vehicle structure is obtained by a hot forming operation on a hybrid panel having a sheet element of light alloy and a sheet of plastic material. The hybrid panel is hot formed by pressing it against a forming surface of a mould element by a pressurized gas or by a second mould element. Following this operation, the hybrid panel assumes a configuration corresponding to the forming surface, whereas the light alloy sheet element and the plastic material sheet constituting the hybrid panel adhere to each other following softening by heat of the plastic material. Before the hot forming step, a surface of said light alloy sheet element which must contact the plastic material sheet is subjected to a roughening treatment, thereby defining surface asperities between which the plastic material of the plastic material sheet is inserted when it is softened by heat.