The invention relates to an apparatus and to a method for establishing a connection having material continuity or having material continuity and shaping matching or for separating such a connection of at least one metal or ceramic component and of a component formed from or by a thermoplastic polymer in which the components to be joined together can be pressed together by a pressing device having a counterholder and a plunger. A heating device is present at the plunger and/or at the counterholder or acts there. A heating of the at least one metal or ceramic component up to above the softening temperature of the component formed from or by polymer can be achieved with the heating device, with the heating device being having at least one electrical resistance heating element that is covered by an electrically insulating, preferably ceramic, protective film, and/or having at least one laser beam that is directed to the metal component(s) within the joining region, and/or having at least one inductor present at the plunger and/or at the counterholder for the inductive heating of the meal component(s).