Schadensanalyse an Gewindeformern

Abstract To optimize the internal thread molding process a failure analyses was done on coated molding tools with different times of service. The investigations should provide basic knowledge for the course of failure and the failure mechanism. The observed system consists of titanium nitride (TiN) coated tools and zinced work pieces. The morphological mutation of the tool surface was observed by scanning electron microscopy (SEM). The metallographic analyses revealed the processes beyond the contact surface, the degradation of the coating and of the substrate material causes by the tribological stress, as well as the metallic microstructure. Specimen in different phases of wear have been investigated and compared with each other. The interpretation of the obtained results allowed the clarification of the failure mechanism and revealed possibilities to acquire the failure history.